EP1844218A1 - Reciprocating internal combustion engine and method of removing exhaust gas particles for one such engine - Google Patents

Reciprocating internal combustion engine and method of removing exhaust gas particles for one such engine

Info

Publication number
EP1844218A1
EP1844218A1 EP06709199A EP06709199A EP1844218A1 EP 1844218 A1 EP1844218 A1 EP 1844218A1 EP 06709199 A EP06709199 A EP 06709199A EP 06709199 A EP06709199 A EP 06709199A EP 1844218 A1 EP1844218 A1 EP 1844218A1
Authority
EP
European Patent Office
Prior art keywords
pressure
chamber
cylinder
engine
flow
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Withdrawn
Application number
EP06709199A
Other languages
German (de)
French (fr)
Inventor
Jean Frédéric Melchior
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Individual
Original Assignee
Individual
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Individual filed Critical Individual
Publication of EP1844218A1 publication Critical patent/EP1844218A1/en
Withdrawn legal-status Critical Current

Links

Classifications

    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
    • F02B—INTERNAL-COMBUSTION PISTON ENGINES; COMBUSTION ENGINES IN GENERAL
    • F02B37/00—Engines characterised by provision of pumps driven at least for part of the time by exhaust
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01N—GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR MACHINES OR ENGINES IN GENERAL; GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR INTERNAL COMBUSTION ENGINES
    • F01N13/00—Exhaust or silencing apparatus characterised by constructional features ; Exhaust or silencing apparatus, or parts thereof, having pertinent characteristics not provided for in, or of interest apart from, groups F01N1/00 - F01N5/00, F01N9/00, F01N11/00
    • F01N13/009—Exhaust or silencing apparatus characterised by constructional features ; Exhaust or silencing apparatus, or parts thereof, having pertinent characteristics not provided for in, or of interest apart from, groups F01N1/00 - F01N5/00, F01N9/00, F01N11/00 having two or more separate purifying devices arranged in series
    • F01N13/0097—Exhaust or silencing apparatus characterised by constructional features ; Exhaust or silencing apparatus, or parts thereof, having pertinent characteristics not provided for in, or of interest apart from, groups F01N1/00 - F01N5/00, F01N9/00, F01N11/00 having two or more separate purifying devices arranged in series the purifying devices are arranged in a single housing
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01N—GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR MACHINES OR ENGINES IN GENERAL; GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR INTERNAL COMBUSTION ENGINES
    • F01N13/00—Exhaust or silencing apparatus characterised by constructional features ; Exhaust or silencing apparatus, or parts thereof, having pertinent characteristics not provided for in, or of interest apart from, groups F01N1/00 - F01N5/00, F01N9/00, F01N11/00
    • F01N13/011—Exhaust or silencing apparatus characterised by constructional features ; Exhaust or silencing apparatus, or parts thereof, having pertinent characteristics not provided for in, or of interest apart from, groups F01N1/00 - F01N5/00, F01N9/00, F01N11/00 having two or more purifying devices arranged in parallel
    • F01N13/017—Exhaust or silencing apparatus characterised by constructional features ; Exhaust or silencing apparatus, or parts thereof, having pertinent characteristics not provided for in, or of interest apart from, groups F01N1/00 - F01N5/00, F01N9/00, F01N11/00 having two or more purifying devices arranged in parallel the purifying devices are arranged in a single housing
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01N—GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR MACHINES OR ENGINES IN GENERAL; GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR INTERNAL COMBUSTION ENGINES
    • F01N3/00—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust
    • F01N3/02—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for cooling, or for removing solid constituents of, exhaust
    • F01N3/021—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for cooling, or for removing solid constituents of, exhaust by means of filters
    • F01N3/023—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for cooling, or for removing solid constituents of, exhaust by means of filters using means for regenerating the filters, e.g. by burning trapped particles
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01N—GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR MACHINES OR ENGINES IN GENERAL; GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR INTERNAL COMBUSTION ENGINES
    • F01N3/00—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust
    • F01N3/02—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for cooling, or for removing solid constituents of, exhaust
    • F01N3/021—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for cooling, or for removing solid constituents of, exhaust by means of filters
    • F01N3/023—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for cooling, or for removing solid constituents of, exhaust by means of filters using means for regenerating the filters, e.g. by burning trapped particles
    • F01N3/0233—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for cooling, or for removing solid constituents of, exhaust by means of filters using means for regenerating the filters, e.g. by burning trapped particles periodically cleaning filter by blowing a gas through the filter in a direction opposite to exhaust flow, e.g. exposing filter to engine air intake
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01N—GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR MACHINES OR ENGINES IN GENERAL; GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR INTERNAL COMBUSTION ENGINES
    • F01N3/00—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust
    • F01N3/02—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for cooling, or for removing solid constituents of, exhaust
    • F01N3/021—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for cooling, or for removing solid constituents of, exhaust by means of filters
    • F01N3/033—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for cooling, or for removing solid constituents of, exhaust by means of filters in combination with other devices
    • F01N3/035—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for cooling, or for removing solid constituents of, exhaust by means of filters in combination with other devices with catalytic reactors, e.g. catalysed diesel particulate filters
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01N—GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR MACHINES OR ENGINES IN GENERAL; GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR INTERNAL COMBUSTION ENGINES
    • F01N3/00—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust
    • F01N3/02—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for cooling, or for removing solid constituents of, exhaust
    • F01N3/037—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for cooling, or for removing solid constituents of, exhaust by means of inertial or centrifugal separators, e.g. of cyclone type, optionally combined or associated with agglomerators
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
    • F02B—INTERNAL-COMBUSTION PISTON ENGINES; COMBUSTION ENGINES IN GENERAL
    • F02B37/00—Engines characterised by provision of pumps driven at least for part of the time by exhaust
    • F02B37/02—Gas passages between engine outlet and pump drive, e.g. reservoirs
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
    • F02D—CONTROLLING COMBUSTION ENGINES
    • F02D13/00—Controlling the engine output power by varying inlet or exhaust valve operating characteristics, e.g. timing
    • F02D13/02—Controlling the engine output power by varying inlet or exhaust valve operating characteristics, e.g. timing during engine operation
    • F02D13/0276—Actuation of an additional valve for a special application, e.g. for decompression, exhaust gas recirculation or cylinder scavenging
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
    • F02M—SUPPLYING COMBUSTION ENGINES IN GENERAL WITH COMBUSTIBLE MIXTURES OR CONSTITUENTS THEREOF
    • F02M26/00—Engine-pertinent apparatus for adding exhaust gases to combustion-air, main fuel or fuel-air mixture, e.g. by exhaust gas recirculation [EGR] systems
    • F02M26/13—Arrangement or layout of EGR passages, e.g. in relation to specific engine parts or for incorporation of accessories
    • F02M26/14—Arrangement or layout of EGR passages, e.g. in relation to specific engine parts or for incorporation of accessories in relation to the exhaust system
    • F02M26/15—Arrangement or layout of EGR passages, e.g. in relation to specific engine parts or for incorporation of accessories in relation to the exhaust system in relation to engine exhaust purifying apparatus
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
    • F02M—SUPPLYING COMBUSTION ENGINES IN GENERAL WITH COMBUSTIBLE MIXTURES OR CONSTITUENTS THEREOF
    • F02M26/00—Engine-pertinent apparatus for adding exhaust gases to combustion-air, main fuel or fuel-air mixture, e.g. by exhaust gas recirculation [EGR] systems
    • F02M26/13—Arrangement or layout of EGR passages, e.g. in relation to specific engine parts or for incorporation of accessories
    • F02M26/22—Arrangement or layout of EGR passages, e.g. in relation to specific engine parts or for incorporation of accessories with coolers in the recirculation passage
    • F02M26/23—Layout, e.g. schematics
    • F02M26/25—Layout, e.g. schematics with coolers having bypasses
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
    • F02M—SUPPLYING COMBUSTION ENGINES IN GENERAL WITH COMBUSTIBLE MIXTURES OR CONSTITUENTS THEREOF
    • F02M26/00—Engine-pertinent apparatus for adding exhaust gases to combustion-air, main fuel or fuel-air mixture, e.g. by exhaust gas recirculation [EGR] systems
    • F02M26/13—Arrangement or layout of EGR passages, e.g. in relation to specific engine parts or for incorporation of accessories
    • F02M26/22—Arrangement or layout of EGR passages, e.g. in relation to specific engine parts or for incorporation of accessories with coolers in the recirculation passage
    • F02M26/23—Layout, e.g. schematics
    • F02M26/28—Layout, e.g. schematics with liquid-cooled heat exchangers
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
    • F02M—SUPPLYING COMBUSTION ENGINES IN GENERAL WITH COMBUSTIBLE MIXTURES OR CONSTITUENTS THEREOF
    • F02M26/00—Engine-pertinent apparatus for adding exhaust gases to combustion-air, main fuel or fuel-air mixture, e.g. by exhaust gas recirculation [EGR] systems
    • F02M26/13—Arrangement or layout of EGR passages, e.g. in relation to specific engine parts or for incorporation of accessories
    • F02M26/35—Arrangement or layout of EGR passages, e.g. in relation to specific engine parts or for incorporation of accessories with means for cleaning or treating the recirculated gases, e.g. catalysts, condensate traps, particle filters or heaters
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01N—GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR MACHINES OR ENGINES IN GENERAL; GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR INTERNAL COMBUSTION ENGINES
    • F01N2290/00—Movable parts or members in exhaust systems for other than for control purposes
    • F01N2290/02—Movable parts or members in exhaust systems for other than for control purposes with continuous rotary movement
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02T—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO TRANSPORTATION
    • Y02T10/00—Road transport of goods or passengers
    • Y02T10/10—Internal combustion engine [ICE] based vehicles
    • Y02T10/12—Improving ICE efficiencies

Definitions

  • a reciprocating internal combustion engine and method for removing particulates from the flue gases for such an alternative engine are provided.
  • the present invention relates to an internal reciprocating engine and a method for removing particles from the flue gases of such an internal combustion engine.
  • Reciprocating internal combustion engines operating on two- or four-stroke cycles and fitted to motor vehicles are subject to frequent and rapid transient operating conditions, as well as severe limitations of pollutants released to the atmosphere.
  • pollutants are mainly NOX nitrogen oxides, CO carbon monoxide, HC unburned hydrocarbons and particulates.
  • Spark ignition engines are generally not associated with a turbocharger unit and they do not emit particles. On the other hand, they emit a lot of nitrogen oxide, carbon monoxide and unburned hydrocarbons which are most often eliminated in a three-way catalytic converter well adapted to stoichiometric mixture combustion. However, the efficiency of this type of engine is degraded by heat losses due to the high temperature of the operating cycle and the pumping work following the rolling of the intake flow. Diesel-type engines are increasingly associated with a turbocharger unit with a single turbocharger that is sufficient to produce an intake pressure of two to three absolute bars.
  • the turbine of the turbocharger is generally variable geometry thus adapting to variations in speed and the variable back pressure of the exhaust line of the engine. Emissions of carbon monoxide and unburned hydrocarbons are low, but nevertheless require an oxidation catalyst in the exhaust line. In addition, nitrogen oxide emissions require recycling of cooled flue gases and particulate emissions are currently limited by the excess of air that generates nitrogen oxides.
  • Diesel-type engines are likely to lose the qualities of efficiency and hardiness that make them prefer to the spark-ignition type engine, despite its higher cost.
  • the after-treatment devices used to date are located downstream of the turbocharger unit turbines and these devices generate a back pressure that can reach 1 bar at full engine power. Under these conditions, the equalization of the turbine expansion ratio and the compressor compression ratio of the turbocharger unit assumes that the exhaust pressure is twice the engine intake pressure. A fortiori, a rate of expansion higher than a compression ratio leads to unacceptable pressure differences between intake and exhaust for very supercharged engines with a high rate of flue gas recirculation. In addition, the downstream temperature of the turbines is often insufficient to initiate catalysis of the treatment device.
  • the upstream post-treatment turbines turbocompression group has already been tried by the manufacturers without success because the main difficulty is due to the volume of the device that dissipates the pressure pulsations of the gases needed to drive the turbocharger group at engine speeds below the engine speed (engine speed where the exhaust pressure crosses the intake pressure).
  • French Patent Application No. 03 03 728 also known in the name of the Applicant, discloses an alternating motor with recirculation of burnt gases or the turbocompression is adapted for an engine speed below the minimum operating speed.
  • One of the aims of the invention is to produce a high supercharging of the high rate of recirculation engines of the flue gases and low exhaust temperature by limiting the exhaust backpressure detrimental to the efficiency of this engine.
  • Another object of the invention is to eliminate the pollutants generated by the cold cycles, essentially carbon monoxide, unburnt hydrocarbons and particles generated by the direct injection of a liquid fuel.
  • the subject of the invention is therefore an internal combustion internal combustion engine comprising, on the one hand, at least one cylinder provided with at least one intake valve and at least one exhaust valve through which a flow is evacuated.
  • pulsed gas whose generating pressure is the pressure Pd prevailing in the cylinder at the opening of said at least one exhaust valve and, secondly, a turbocharging unit actuated by said burnt gas and said supply to less cylinder compressed air cooled, characterized in that at least a portion of the pulsed flow of burnt gas is discharged from said at least one cylinder by an exhaust pipe provided with an expansion nozzle opening tangentially to a peripheral wall of a bedroom revolution centrifugation and perpendicular to the axis of this chamber and in that the centrifugation chamber communicates with a turbocompressor group turbocharger supply duct by an annular radial diffuser coaxial with said chamber and having an inlet diameter D, the static pressure in the centrifuge chamber being maintained at a value Ps lower than the pressure Pd in order to accelerate
  • the centrifugation chamber comprises an axial orifice of diameter d smaller than the inlet diameter D of the radial diffuser communicating with a recycle line for the flue gases and in that the volume of a space comprised between a dummy cylinder of diameter D and a coaxial cylinder of diameter d of lengths equal to the distance between the axial orifice and the inlet of the radial diffuser is preferably greater than two unit cubic capacities of the engine,
  • the centrifugation chamber has a volume greater than at least three times the unit cubic capacity of the motor in order to stabilize the static pressure when the axial orifice is closed; the centrifugation chamber communicates via the axial orifice with a volume at less than three engine unit displacements to stabilize the static pressure,
  • the centrifugation chamber communicates with the recycling duct via the axial orifice, the static pressure at said orifice being substantially equal to the intake pressure of the engine,
  • the axial orifice supplies an annular radial diffuser having an inlet diameter, the static pressure at said axial orifice being lower than the intake pressure of the engine;
  • said at least one nozzle opens into said centrifugation chamber at a substantially conical section extending between a zone of greater diameter of said chamber and said axial orifice of diameter d, the second exhaust valve is connected by a discharge duct to the recycling duct downstream from the corresponding axial orifice, the exhaust valve of the second duct opening after the exhaust valve of the first duct when the pressure in the corresponding cylinder has dropped sufficiently,
  • the motor comprises between the annular radial diffuser of the supply duct of the turbocharger group turbines and said turbines, an axial flow particle filter, preferably a cylindrical filter associated with means for removing the particles deposited on the filter; with particles, the means for removing the particles comprise a collector applied to the inlet face of the particle filter and movable on this face to periodically sweep the entire surface of this face, said collector communicating with an area where the static pressure is less than the pressure downstream of the particulate filter to create a flow of countercurrent gas in the sector of this filter covered by the manifold,
  • the collector communicates with the recycling duct to burn the particles extracted from said particulate filter in said at least cylinder,
  • the collector communicates with an axial zone of the centrifugation chamber in the vicinity of the radial diffuser of the turbine supply duct, by a combustion zone of the particles situated in said chamber, and
  • the particle filter has the shape of a cylinder of revolution whose two end faces are flat, said collector being rotated about the axis of this filter.
  • the subject of the invention is also a method for removing particles from the flue gases of an internal combustion reciprocating engine as previously mentioned, characterized in that:
  • the evacuated flue gases are passed through an axial flow particle filter, and each sector of the inlet face of the particulate filter is periodically brought into communication with an area where the static pressure is lower than the downstream pressure. of this particle filter to create a flow countercurrent gases in each sector of said particulate filter which carries particulates taken from said filter to an area where said particles are burned.
  • the zone where the static pressure is lower than the pressure downstream of the particulate filter is formed by a flue gas recycling circuit provided with a valve for regulating the flow of recycled gas; particles removed being burned in said at least engine cylinder,
  • the zone where the static pressure is lower than the pressure downstream of the particulate filter is formed by an axial zone of a centrifugation chamber;
  • the axial zone communicates with the recycling circuit, the particles removed being burned in the at least one cylinder of the engine,
  • the axial zone communicates with the turbocharging unit, the particles removed being burned in the centrifugation chamber.
  • FIG. 1 is a diagram of an example of an assembly for exhausting burnt gases and supplying oxidant to an internal combustion reciprocating engine according to the invention
  • FIG. 2 is a diagrammatic view on a larger scale and in axial section of a centrifugation chamber of the pulsed flow of burnt gases emitted by the engine;
  • FIG. 3 is a sectional view along the line 3-3 of FIG. 2
  • FIG. 4 and 5 are diagrammatic views in axial section of two variants of the centrifugation chamber
  • FIG. 6 and 7 are diagrammatic views respectively in axial section and along the line 7-7 of the centrifugation chamber associated with means for removing particles from the flue gas,
  • - Figs. 8 to 9 are schematic views in axial section of two variants of the flue gas removal means
  • - Figs. Figures 10 to 12 are diagrams of several examples of flue gas discharge and oxidizer feed systems of a four-cylinder reciprocating internal combustion engine.
  • FIG. 1 schematically shows a motor 1 which comprises at least one cylinder 1a provided with at least one intake valve 2 and at least one exhaust valve 3.
  • the cylinder 1a is provided with an intake valve
  • the engine 1 is associated with a set of means which will be described later and which allows to deliver to this engine 1 a mixture of clean air and burnt gases whose pressure, temperature and the rate of recycled gas are adjustable at any time depending on the operating parameters of the moment.
  • the intake valve 2 is connected to an intake manifold 4 and the exhaust valve 3 is connected to an exhaust duct 5 which opens into a centrifuge chamber designated by the general reference 10.
  • This centrifuge chamber 10 transforms the pulsed flow of burnt gases emitted by the cylinder 1a of the engine 1 in two flows, respectively a flow designated by Qt and a flow designated by Qegr, at substantially constant pressures.
  • the flow Qt is directed towards a turbocharger group generally designated by the reference 30.
  • This turbocompression unit 30 relaxes the flow Qt to reject it to the atmosphere and takes the atmospheric air designated by Qair to feed the cylinder 1a of the motor 1 via a duct 6, a mixer 7 and the intake manifold 4.
  • the turbocharger unit 30 is connected to the centrifugation chamber 10 via a duct 31.
  • the fresh air flow Qair is advantageously compressed, in a conventional manner, in the turbocharger unit 30, for example a first time by a low pressure turbocharger, and is then cooled before being compressed a second time by a high-pressure turbocharger and cooled a second time.
  • the Qt flow which represents 50 to 70% of the flue gas flow, equal to the fresh air flow Qair plus the burned fuel flow is successively relaxed in the high pressure turbine and the low pressure turbine before being released into the atmosphere.
  • the flow Qt can feed the high-pressure turbine and the low-pressure turbine of the turbocharger unit 30 in parallel.
  • the flow Qegr, at the outlet of the centrifugation chamber 10, is directed towards a recycling circuit which comprises a conduit 35.
  • the recycling circuit Downstream of the assembly formed by the dispensing valve 36, the refrigerant 37 and the duct bypass 38, the recycling circuit comprises a flow control valve 39 Qegr connected to the mixer 7 by a conduit 40.
  • the mixer 7 receives Qair flow and Qegr to supply the cylinder 1a of the engine 1 with a homogeneous combustion mixture.
  • the flow Qegr which represents 30 to 50% of the flue gas stream is cooled under pressure and adjustably in the coolant 37, then intimately mixed with the flow of fresh air Qair in the mixer 7 to supply the intake manifold 4.
  • the adjustment of the flow temperature Qegr can advantageously be carried out by short-circuiting by the distributor valve 36 all or part of the flow flowing in the coolant 37.
  • the conduit 31 connecting the centrifugation chamber 10 to the turbocharger unit may be equipped with a post-processing system designated by the general reference 50 and will be described later.
  • the limitation to about 1600 ° K of the maximum temperature of the operating cycle of the engine 1 causes a proportional limitation of the temperature at the end of expansion in the cylinder 1a, available for turbocharging.
  • the power of the turbines of the turbocharger unit 30 is based on the total pressure of the flow Qt. It is therefore seen that it is advantageous to exploit optimally the generating pressure Pd available in the exhaust gases at the end of expansion in the cylinder 1a.
  • the distribution and the circulation of the gas flows in the centrifugation chamber 10 are organized in an original way to optimize the use of this pressure in the context mentioned above. First of all, some physical bases of the operation of the reciprocating internal combustion engine are recalled.
  • Pd / Pc Vc / Vd x Td / Tc
  • Pd, Vd, Td and Pc, Vc, Tc are respectively the pressure, the volume and the temperature of the gases at the end of expansion and at the beginning of compression.
  • Pd / Vc can be set by playing Vc / Vd at constant inlet temperature. With fixed valve timing, Pd / Pc can be adjusted by adjusting the intake temperature. A fortiori, Pd / Pc can be adjusted by adjusting the two parameters to adjust another variable of the cycle, the compression temperature Pc which governs ignition, for example. For a given intake pressure, the pressure generating the flue gases can thus be adjusted by parameters internal to the engine (valve timing) or by external parameters (intake temperature).
  • Half of the burnt gases present in the cylinder 1a can, in this embodiment, be expanded from a generating pressure greater than Pc, generating pressure whose mass average is 1, 5 Pc.
  • one half of the hot gases is intended to be cooled and transferred into the intake manifold 4 where the pressure is close to Pc.
  • the other half is intended to be expanded in turbines of the turbocharger unit to atmospheric pressure.
  • the centrifuge chamber 10 is designed to direct the most energetic flue gases to the turbocharger turbines 30 and the least energy gases to the recycle conduit 35. In effect, the transfer of the recycled flow Qegr from the chamber centrifugation 10 to the intake manifold 4 can be carried out at a pressure close to Pc, if the recycling duct is sufficiently sized.
  • the discharge work of the recycled gases of the cylinder 1a is developed by the piston of this cylinder in the case of an engine operating in a four-stroke cycle or by the fresh charge in the case of a motor operating in a two-cycle cycle. time.
  • the centrifugation chamber 10 has a general shape of revolution of axis XX.
  • the peripheral wall 11 of this chamber of revolution has the shape of a cylinder.
  • the exhaust duct 5 placing the cylinder chamber 1a in communication with the centrifugal chamber 10 when opening the exhaust valve 3, is provided at its free end with a thrust nozzle 12 opening tangentially to the wall 11 of this centrifugation chamber 10 and perpendicular to the axis XX of said centrifuge chamber.
  • a thrust nozzle 12 opening tangentially to the wall 11 of this centrifugation chamber 10 and perpendicular to the axis XX of said centrifuge chamber.
  • this speed can approach the speed of sound and decreases to 0 when the pressures equalize.
  • the axisymmetric field of the static pressures in the centrifugation chamber 10 is governed by the centrifugation effect which itself depends on the evolution of the tangential velocities along a radius of this chamber 10.
  • the fastest burned gases are placed therefore naturally towards the periphery of the centrifuge chamber 10 while the slower burned gases are concentrated around the axis XX of this chamber 10.
  • the static pressure and the total pressure decrease simultaneously between the periphery of the centrifuge chamber 10 and its axis XX where the static pressure can decrease significantly below the pressure at the beginning of compression Pc.
  • the total pressure of the fast gases is equal to the static pressure increased by the dynamic pressure while the pressure at the outlet of the nozzle 12 is the static pressure minus the dynamic pressure.
  • the centrifugation chamber 10 is dimensioned to limit the kinetic energy losses by friction of the gas ring against the walls of this chamber. The time of presence of the fast gases in the centrifuge chamber 10 must therefore be minimal. As shown in FIG. 2, to stabilize the static pressures in the centrifuge chamber 10, this centrifugation chamber 10 is sufficiently large or according to FIG. 5 communicates through at least one axial orifice 13 of diameter d less than the largest diameter of the centrifuge chamber 10 with a volume 14 communicating with the recycle conduit 35 and which has a large volume relative to the amplitude of the pulses. The orifice 13 sees the breathing of the chamber 10 when the ring C formed by the fast flue gas is inflated and depleted to the rhythms of the openings and closings of the exhaust valve 3.
  • the fast gases Qt are collected in the toric zone of the centrifugation chamber 10 in the form of the ring C and in which the diameter of this chamber 10 is greater than the diameter d of the orifice 13.
  • the volume of this zone toric must be greater than the amplitude of the high-volume pulsations Qt fast and this amplitude varies between one and two cubic units for a four-stroke engine and four-cylinder.
  • the centrifugation chamber 10 communicates with the turbine feed duct 31 of the turbocharger unit 30 by an annular radial diffuser 15 coaxial with said chamber 10 and having a minimum inlet diameter D.
  • the inlet diameter D of the radial diffuser 15 is equal to the largest diameter of the centrifuge chamber 10.
  • the centrifuge chamber 10 has a diameter D along its entire length.
  • the radial diffuser 15 thus extends externally the fast-gas collecting zone Qt in the centrifugation chamber 10 to collect and slow down these fast gases.
  • This diffuser 15 is advantageously formed by two parallel walls 16 and 17 extending perpendicularly to the axis XX of the centrifuge chamber 10 and delimiting therebetween a space 18 for the passage of fast gases Qt.
  • the flow rate of these fast gases Qt which through the diffuser 15 is controlled by the turbines of the turbocharger group 30.
  • the flow rate of the gas flow Qt is a function of the width of the space 18, that is to say the distance separating the walls 16 and 17 of the radial diffuser 15, and the turbine section of the turbocharger group 30.
  • the static pressure in the centrifuge chamber 10 is maintained at a value Ps lower than the pressure Pd in order to accelerate a fraction of the flue gas supplying the ring of burnt gases.
  • C in motion rapid rotation about the axis XX of the centrifuge chamber 10 and which escapes to the turbines of the turbocharger group 30 by compressing and slowing down in the radial diffuser 15.
  • the centrifugation chamber 10 has a volume at least equal to three cubic units.
  • the recycled Qegr gases can be recompressed in a radial diffuser 20, as will be described later.
  • the centrifugation chamber 10 has a reduced volume to limit the wetted surface by the rapidly rotating gas ring and communicates through the orifice 13 with a volume 14 at least equal to three cubic units.
  • the inlet of the radial diffuser 15 may have a diameter D less than the maximum diameter of the centrifugation chamber 10.
  • the volume of a space between a dummy cylinder of diameter D and a cylinder Dummy coaxial of diameter d of lengths equal to the distance between the orifice 13 of diameter d and the diameter of inlet D of the radial diffuser 15 is preferably greater than two cubic units of the engine in order to maintain all the fast gases in the chamber 10 during the volume breaths of the rotating gas ring.
  • the burnt gases still present in the cylinder 1a of the engine are discharged at low speed by the piston in the case of a motor operating in a four-stroke cycle or the fresh load in the case of an engine operating in a two-stroke cycle.
  • These slow gases must reach the axial zone of the centrifugation chamber 10, mixing as little as possible with fast gases.
  • the slow gases Qegr are partially mixed with the fast gases before being slowed down by an annular radial diffuser 20 which puts the centrifugation chamber 10 in communication with the recycling conduit 35.
  • This radial diffuser 20 has a minimum diameter substantially equal to diameter d of the outlet orifice 13.
  • the radial diffuser 20 is formed of two parallel walls, respectively 21 and 22, extending perpendicularly to the axis XX of the centrifuge chamber 10 and delimiting therebetween a gap 23 for passage of the slow gases Qegr.
  • the total pressure at the inlet of this diffuser 20 is substantially at the intake pressure Qad of the engine 1 and the static pressure in said chamber 10 may be below this inlet pressure Pad.
  • the radial diffuser 20 raises the pressure of the slow gas flow Qegr at the intake pressure in the manifold 4 of the engine 1.
  • the radial diffuser 20 is optional in the case of a motor operating in a four-cycle cycle where the slow gas flow Qegr is pumped by the engine. On the other hand, it is necessary to create a slow gas flow Qegr in a motor operating in a two-cycle cycle.
  • each of the diffusers 15 and 20 is smooth and the ratio of diameters D / d of these two diffusers sets the potential of the slow gas flow Qegr.
  • the flow rate of Qegr gas to be recycled in the cylinder 1a is preferably and as shown in FIG. 2, idle by the radial diffuser 20 to supply either the exchanger 4 cooled by the hot cooling water of the engine 1 and which is optionally followed by a second exchanger cooled by a low temperature water circuit, not shown, or the bypass duct 38.
  • the control valve 36 modulates the cooled fraction of the Qegr gas flow and the recycling valve 39 located upstream or downstream of the exchanger 37 to adjust the flow Qegr.
  • the burnt gases thus cooled, the flue gases passing through the bypass duct 38 and the fresh air Qair are intimately mixed in the mixer 7 before entering the intake manifold 4 and the cylinder 1a through the intake valve 2 .
  • the Qegr Recycled Gas Flow Valve is very effective for transient engine operation to increase the amount of oxygen available for combustion of this engine. Indeed, it increases the Qt gas flow through the turbines turbocharger group 30 at the expense of recycled gas flow Qegr instantly replaced by fresh air. This maneuver, which moves the splitting points in the characteristic diagrams of the compressors, is done without waiting Turbocharger group turbocharging. In steady state, this method of increasing the pumping work done by the piston is used only for fine adjustments. Generally, it is preferred to adjust the flow of recycled Qegr gas by changing the valve timing or by operating the temperature control valve 36 of Qegr.
  • the slow gases take the same exhaust duct 5 as the fast gases that open into the centrifuge chamber 10 via the expansion nozzle 12. separation of these two streams, ie the fast gas flow and the slow gas flow then takes place in this centrifuge chamber 10.
  • the nozzle 12 opens, as shown in FIG. 4, in a conical zone of the centrifuge chamber 10 connecting a large diameter area to a small diameter area.
  • the outer wall 11 of the centrifugation chamber 10 forms a cone along the entire length of this centrifugation chamber 10, the conicity of this wall being directed towards the outlet orifice 13. of diameter d.
  • the gases from the expansion nozzle 12 are oriented alternatively to the smaller diameter zone or to the larger diameter zone depending on their ejection speed.
  • the section of the nozzle 12 must be small enough to accelerate the fast gases and large enough not to brake the slow gases.
  • the dimensioning of the exhaust duct 5 can be chosen according to the desired goals.
  • the mass of gas immobilized in this duct 5 when the exhaust valve 3 is closed is propelled towards the centrifugation chamber 10 by the expansion of the gases of the next cycle which will lose momentum.
  • the gaseous column thus accelerated in the conduit 5 entrains behind it by inertia a fraction of the low energy gases still present in the cylinder 1a. This double exchange of momentum degrades the energy differentiation between the Qt gas flow and the Qegr gas flow.
  • the volume of the conduit 5 must be minimal.
  • the volume of the duct 5 is preferably close to the engine capacity of the engine.
  • valve 3a In the case of an AC motor provided with two exhaust valves 3a and 3b per cylinder 1a, a valve such as valve 3a, for example, is assigned to fast gases and a valve, such as valve 3b, is assigned to slow gases, as shown in FIG. 5.
  • the fast gases take a duct 5a equipped with an expansion nozzle 12 and opening out at the periphery of the centrifugation chamber 10, like the exhaust duct 5 described above, whereas the slow gases take a second exhaust duct 5b. which emerges downstream of the outlet orifice 13.
  • the internal volume of the centrifugation chamber 10 is separated into two volumes located on either side of the transverse partition 13a in which is formed the outlet port 13, a first volume in which are directed the fast gases from the exhaust valve 3a and a second volume in which are directed the slow gases from the exhaust valve 3b.
  • the outlet orifice 13 then sees an alternating flow flow.
  • the nozzle 12 fed exclusively by fast gases may have a smaller section than the previous embodiment.
  • the valve 3a of the exhaust duct 5a opens first and when the pressure in the cylinder 1a has dropped sufficiently, the exhaust valve 3b of the duct 5b opens in turn to drain the cylinder 1a.
  • the two valves 3a and 3b can close simultaneously at the end of the transfer, the separation of gases in two flows then taking place in the cylinder 1a of the engine.
  • the quantity of burnt gases emitted by the engine is proportional to its operating regime.
  • the flow of gas Qt is proportional to the section offered to the gases for venting to the atmosphere, in this case the section of an orifice equivalent to the turbines of the turbocharger unit 30 as well as the supply pressure of the turbocharger units. turbines, it itself depends on the efficiency of the radial diffuser 15.
  • the minimum turbine section In order to guarantee the clearance of nitrogen oxide from the minimum operating speed of the engine, it is therefore necessary for the minimum turbine section to allow only about 60% of the flow of gas emitted by the engine to pass at its minimum speed. use.
  • the ratio between the gas flow rate Qt and the gas flow rate Qegr can be adjusted by the engine valve timing, by the turbocharger group turbines section, by the recycling valve 39 or by the valve 36 which regulates the temperature of the flow Qegr, as mentioned in the patent application No. 03 03 728 also in the name of the Applicant.
  • the ratio Qt / Qegr can also be adjusted by modifying the width of the space 18 formed between the walls 16 and 17 of the radial diffuser 15 or by the width of the space 23 formed between the walls 21 and 22 of the radial diffuser 20.
  • the wall 22 of the radial diffuser 2 may be displaceable by any appropriate type of means along the axis XX of the centrifugation chamber 10 to close the orifice 13.
  • the movable wall 22 replaces the valve recycling 39.
  • the work done by the turbocharger group turbines increases with the temperature and the total pressure of the gases that feed them.
  • the adjustment of the power of the turbines is done essentially by adjusting the total pressure of the gas flow Qt using the actuators internal to the engine (valve timing and injection) and / or the external actuators (valve 39 and / or valve 36 of the Qegr gas flow circuit).
  • the total pressure of the gas flow Qt is approximately the sum of the static pressure prevailing in the centrifuge chamber 10 and the dynamic pressure associated with the speed of rotation of the gases.
  • the report between these two components can be chosen by adjusting the level of the static pressures in this centrifugation chamber 10.
  • this adjustment can be done by throttling of the gas flow recycle line Qegr.
  • the recycle valve 39 When the recycle valve 39 is closed, the dynamic pressure starts from a maximum value to cancel when the expansion ratio in the nozzle 12 is equal to unity.
  • the annular radial diffuser 15 automatically adapts to intermediate aerodynamic speeds. Indeed, for a high dynamic pressure, the gas flow Qt penetrates tangentially into the annular space 18 to undergo diffusion. For a zero dynamic pressure, the gas flow Qt radially passes through the diffuser 15 without loss of load.
  • the reciprocating internal combustion engine is equipped with after-treatment devices 50 of the gas flow Qt and which are situated between the annular radial diffuser 15 and the turbine inlet of the turbocharger unit 30.
  • These post-treatment devices are formed by a catalytic particle filter 51 with axial flow and preferably cylindrical.
  • the filter 51 is traversed by the flow of Qt gas at the outlet of the radial diffuser 15 whose temperature is always greater than 400 0 C, sufficient temperature for the catalytic oxidation of unburned hydrocarbons and carbon monoxide, but insufficient to burn the deposited particles which oxidize rapidly only above 600 ° C.
  • a first method consists of allowing a certain weight of particles to accumulate at the inlet of the filter 51 and of burning these particles locally by periodically raising the temperature of the particles. gas passing through the particulate filter, for example by discharging into the atmosphere a portion of the air delivered by the high pressure compressor. The regeneration of the particulate filter 51 is all the more rapid as it is frequent.
  • the heavy particles centrifuged in the radial diffuser 15 are concentrated on a cylindrical surface 52 arranged at the outlet of the radial diffuser 15 and upstream of the particle filter 51, with respect to the direction of flow of the gas flow Qt.
  • the particulate filter 51 is associated with particle removal means which comprises a manifold 55 applied to the inlet surface 51a of the particulate filter 51.
  • the manifold 55 is movable on this face to periodically scan the the entire surface of the face 51a of the particulate filter 51.
  • the collector 55 communicates with an area where the static pressure is lower than the pressure downstream of the particulate filter 51 to create a countercurrent flow of gas in the sector of the filter 51 covered by the collector 55.
  • the collector 55 is rotated by a suitable means 56, such as an electric motor 56 whose speed is adjusted to ensure a complete cleaning cycle of the particle filter 51, for example every second.
  • the collector 55 is connected by a duct 57 located in the axis XX of the centrifugation chamber 10 and which opens out at the outlet orifice 13 where the static pressure is lower than the pressure downstream of the particle filter 51.
  • a small fraction of the filtered flow returns the small sector of the particulate filter 51 covered by the collector 55, against the current to entrain the particles which have just deposited there towards the end of the conduit 57.
  • the particles thus collected can to be reintroduced into the cylinder 1a with the recycled gases to be burned.
  • the sweep flow thus formed then participates in the flow rate of the gas flow Qegr.
  • a zone 60 of combustion of these particles can be created in an axial zone of the centrifugation chamber 10, as shown in FIG. 8.
  • the particle-free gas stream is then vented to the turbocharger group turbines 30 through the particulate filter 51 and then participates in the flow rate of gas Qt.
  • the flow of this flow of gas without particle can be regulated by a flame catch 61 formed for example by a cone in order to maintain an adequate richness in the combustion zone 60.
  • an oxidation catalyst 62 separated from the particulate filter 51 may be disposed between the radial diffuser 15 and this particulate filter 51.
  • the sticky soluble particles are burned in the oxidation catalyst 62 before entering the the particulate filter 51 which stops only the dry particles readily entrained by the recirculated gas stream from the manifold 55.
  • the aforementioned particle removal methods can be used separately or in combination.
  • Figs. 10 to 12 there are shown several examples of configuration of the flue gas discharge circuit and the combustion circuit of a four-cylinder reciprocating internal combustion engine. Other configurations can of course be considered.
  • the engine 1 comprises four cylinders 1a each provided with an intake valve 2 and an exhaust valve 3.
  • the exhaust valve 3 of each cylinder 1a is connected to an exhaust pipe 5 which opens in the centrifugation chamber 10 identically to the previous embodiments, that is to say via an expansion nozzle.
  • the engine 1 has four cylinders 1a each provided with an intake valve 2 and an exhaust valve 3.
  • the exhaust valves 3 of two cylinders 1a contiguous are arranged side by side and are each connected by a connecting duct 5a to the exhaust duct 5 which opens into the centrifugation chamber 10.
  • Each exhaust duct 5 is equipped with a nozzle arranged in the centrifugation chamber 10 in a manner identical to the previous modes of centrifugation. production.
  • the engine 1 comprises four cylinders 1a each equipped with two intake valves, respectively 2a and 2b, and two exhaust valves respectively 3a and 3b.
  • the exhaust valves 3a and 3b of two cylinders 1a contiguous are arranged side by side.
  • the exhaust valve 3a of each cylinder 1a is assigned to fast gases and the valve 3b is assigned to the slow gases.
  • the exhaust valve 3a of a cylinder 1a is connected by a connecting pipe 5a to the exhaust valve 3a of the adjoining cylinder 1a and this exhaust valve 3a is connected to the exhaust pipe 5 provided with a nozzle of small section which opens into the centrifuge chamber 10 in the same manner as the previous embodiments.
  • the exhaust valves 3b are connected to each other by a recycling duct 35, which is largely dimensioned to an assembly designated by A which groups together the elements of the Qegr gas recycling circuit as well as the mixer 7.
  • the flow rate of gas recovered by the manifold 55 is directly channeled through the conduit 51 to the assembly A to be sucked by the engine 1.
  • the valves 3a open first to reduce the pressure in the cylinders. Valves 3b then open for the discharge of slow gases.
  • the invention is particularly advantageous for a thermodynamic cycle with a high rate of recycling of flue gas (30 to 50% of the oxidizing mass) which at no time has the favorable conditions for the formation of thermal nitrogen oxides.
  • This constraint boils down to never exceed a local temperature of 1900 0 K approximately.
  • the maximum temperature of the cycle at each point of the combustion chamber is the sum of the local temperature at the start of combustion Tcomb (compression temperature) and the temperature rise due to combustion (Tcomb). This maximum local temperature depends primarily on internal engine parameters such as the compression ratio that governs Tcomb, the local fuel concentrations and the ignition advance that govern Tcomb.
  • This temperature also depends on the admission conditions such as the chemical composition of the oxidizing mixture that governs the oxygen concentration, the Tad admission temperature that governs Tcomb and the intake pressure Pad that governs the mass of oxidizing gas to be heated. .
  • the specificity of these cycles is a high inlet pressure to introduce into the cylinder burnt gases that add to the fresh air required by the combustion and a low exhaust temperature resulting from the reduction of the combustion temperature.
  • the turbocharging system must therefore provide more work with less energy.
  • the reciprocating internal combustion engine according to the invention avoids these disadvantages.
  • the reciprocating engine according to the invention has the advantage of collecting in a single pressurized module the operations of turbocompression, refrigeration, the physical and chemical post-treatment of the gases emitted into the atmosphere, thereby reducing its cost.
  • the reciprocating engine according to the invention also makes it possible to neutralize exhaust noise at the source in order to simplify or even eliminate the silencer downstream of the turbocharger group turbines.

Landscapes

  • Engineering & Computer Science (AREA)
  • Chemical & Material Sciences (AREA)
  • Combustion & Propulsion (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Supercharger (AREA)
  • Exhaust-Gas Circulating Devices (AREA)

Abstract

The invention relates to a reciprocating internal combustion engine comprising at least one cylinder (1a) which is equipped with at least one intake valve (2) and at least one exhaust valve (3). The pulsed exhaust gas flow is released from the cylinder (1a) through an exhaust pipe (5) which is equipped with an expansion nozzle that opens tangentially to a peripheral wall of a rotating centrifuge chamber (10) and perpendicularly to the axis of said chamber. The centrifuge chamber (10) communicates with a supply pipe to the turbines of a turbocharging unit (30) by means of an annular radial diffuser.

Description

Moteur alternatif à combustion interne et procédé d'élimination des particules des gaz brûlés pour un tel moteur alternatif.A reciprocating internal combustion engine and method for removing particulates from the flue gases for such an alternative engine.
La présente invention concerne un moteur alternatif à combustion interne ainsi qu'un procédé d'élimination des particules des gaz brûlés d'un tel moteur alternatif à combustion interne.The present invention relates to an internal reciprocating engine and a method for removing particles from the flue gases of such an internal combustion engine.
Les moteurs alternatifs à combustion interne fonctionnant sur des cycles à deux ou à quatre temps et équipant les véhicules automobiles sont soumis à des régimes de fonctionnement transitoires fréquents et rapides, ainsi qu'à des limitations sévères des polluants rejetés à l'atmosphère. Ces polluants sont essentiellement des oxydes d'azote NOX, du monoxyde de carbone CO, des hydrocarbures imbrûlés HC et des particules.Reciprocating internal combustion engines operating on two- or four-stroke cycles and fitted to motor vehicles are subject to frequent and rapid transient operating conditions, as well as severe limitations of pollutants released to the atmosphere. These pollutants are mainly NOX nitrogen oxides, CO carbon monoxide, HC unburned hydrocarbons and particulates.
A ce jour, les moteurs alternatifs à combustion interne fonctionnant selon le cycle à quatre temps sont les plus couramment utilisés et sont de type à allumage commandé ou de type diesel.To date, reciprocating internal combustion engines operating on the four-stroke cycle are the most commonly used and are of the spark ignition or diesel type.
Les moteurs de type à allumage commandé ne sont généralement pas associés à un groupe de turbocompression et ils n'émettent pas de particules. Par contre, ils émettent beaucoup d'oxyde d'azote, de monoxyde de carbone et d'hydrocarbures imbrûlés qui sont le plus souvent éliminés dans un pot catalytique à trois voies bien adapté à la combustion en mélange stoechiométrique. Mais, le rendement de ce type de moteur se dégrade par des pertes de chaleur dues à la température élevée du cycle de fonctionnement et au travail de pompage consécutif au laminage du flux d'admission. Les moteurs de type diesel sont de plus en plus associés à un groupe de turbocompression comportant un seul turbocompresseur qui suffit pour produire une pression d'admission de deux à trois bars absolus.Spark ignition engines are generally not associated with a turbocharger unit and they do not emit particles. On the other hand, they emit a lot of nitrogen oxide, carbon monoxide and unburned hydrocarbons which are most often eliminated in a three-way catalytic converter well adapted to stoichiometric mixture combustion. However, the efficiency of this type of engine is degraded by heat losses due to the high temperature of the operating cycle and the pumping work following the rolling of the intake flow. Diesel-type engines are increasingly associated with a turbocharger unit with a single turbocharger that is sufficient to produce an intake pressure of two to three absolute bars.
La turbine du turbocompresseur est généralement à géométrie variable permettant ainsi de s'adapter aux variations de régime et à la contre pression variable de la ligne d'échappement du moteur. Les émissions de monoxyde de carbone et d'hydrocarbures imbrûlés sont faibles, mais nécessitent néanmoins un catalyseur d'oxydation dans la ligne d'échappement. Par ailleurs, les émissions d'oxyde d'azote imposent un recyclage de gaz brûlés refroidis et les émissions de particules sont actuellement limitées par l'excès d'air qui est générateur d'oxydes d'azote.The turbine of the turbocharger is generally variable geometry thus adapting to variations in speed and the variable back pressure of the exhaust line of the engine. Emissions of carbon monoxide and unburned hydrocarbons are low, but nevertheless require an oxidation catalyst in the exhaust line. In addition, nitrogen oxide emissions require recycling of cooled flue gases and particulate emissions are currently limited by the excess of air that generates nitrogen oxides.
Mais, les normes appliquées prochainement aux moteurs à combustion interne et notamment aux moteurs de type diesel obligent les constructeurs à intégrer un filtre à particules régénérable dans la ligne d'échappement. Mais, cette disposition a pour principal inconvénient de dégrader sévèrement la turbocompression et les performances du moteur.But the standards soon applied to internal combustion engines and especially to diesel-type engines require manufacturers to incorporate a regenerable particulate filter in the exhaust line. But, this provision has the main disadvantage of severely degrade turbocharging and engine performance.
Les moteurs de type diesel risquent de ce fait de perdre les qualités de rendement et de rusticité qui le font préférer au moteur de type à allumage commandé, malgré son coût plus élevé.Diesel-type engines are likely to lose the qualities of efficiency and hardiness that make them prefer to the spark-ignition type engine, despite its higher cost.
Les dispositifs de post-traitement utilisés jusqu'à ce jour, sont situés en aval des turbines du groupe de turbocompression et ces dispositifs génèrent une contre-pression qui peut atteindre 1 bar à pleine puissance du moteur. Dans ces conditions, l'égalité du taux de détente des turbines et du taux de compression des compresseurs du groupe de turbocompression suppose que la pression d'échappement soit le double de la pression d'admission du moteur. A fortiori, un taux de détente supérieur à un taux de compression conduit à des différences de pression entre l'admission et l'échappement inacceptables pour les moteurs très suralimentés à fort taux de recyclage des gaz brûlés. De plus, la température en aval des turbines est souvent insuffisante pour amorcer la catalyse du dispositif de traitement.The after-treatment devices used to date are located downstream of the turbocharger unit turbines and these devices generate a back pressure that can reach 1 bar at full engine power. Under these conditions, the equalization of the turbine expansion ratio and the compressor compression ratio of the turbocharger unit assumes that the exhaust pressure is twice the engine intake pressure. A fortiori, a rate of expansion higher than a compression ratio leads to unacceptable pressure differences between intake and exhaust for very supercharged engines with a high rate of flue gas recirculation. In addition, the downstream temperature of the turbines is often insufficient to initiate catalysis of the treatment device.
Pour toutes ces raisons, il est plus logique d'exécuter les posttraitements en amont des turbines où la température est plus favorable à la catalyse où la pression réduit la perte de charge. De plus, dans le cas des moteurs fonctionnant selon un cycle à quatre temps, les évolutions de cette perte de charge n'affectent pas la turbocompression et donc l'alimentation en air du moteur.For all these reasons, it is more logical to carry out aftertreatments upstream of turbines where the temperature is more favorable to catalysis where the pressure reduces the pressure drop. In addition, in the case of engines operating on a four-stroke cycle, the changes in this pressure drop do not affect the turbocompression and therefore the air supply of the engine.
Le post-traitement en amont des turbines du groupe de turbocompression a déjà été essayé par les constructeurs sans succès car la principale difficulté est due au volume du dispositif qui dissipe les pulsations de pression des gaz nécessaires à l'entraînement du groupe de turbocompression aux régimes du moteur inférieurs au régime d'adaptation (régime du moteur où la pression d'échappement croise la pression d'admission). On connaît dans la demande de brevet en France n° 03 03 728 également au nom du Demandeur, un moteur alternatif à recirculation de gaz brûlés ou la turbocompression est adaptée pour un régime moteur inférieur au régime minimal d'utilisation.The upstream post-treatment turbines turbocompression group has already been tried by the manufacturers without success because the main difficulty is due to the volume of the device that dissipates the pressure pulsations of the gases needed to drive the turbocharger group at engine speeds below the engine speed (engine speed where the exhaust pressure crosses the intake pressure). French Patent Application No. 03 03 728, also known in the name of the Applicant, discloses an alternating motor with recirculation of burnt gases or the turbocompression is adapted for an engine speed below the minimum operating speed.
Dans ces conditions, une suralimentation à pression constante s'installe dès le régime minimal d'utilisation du moteur, indépendamment du volume du collecteur d'échappement.Under these conditions, a constant pressure supercharging is installed from the minimum operating speed of the engine, regardless of the volume of the exhaust manifold.
Néanmoins, le mauvais rendement isentropique des très petites turbomachines adaptées aux moteurs des véhicules automobiles associé à la basse température des gaz générés par les cycles froids, impliquent une pression totale des gaz à l'entrée des turbines supérieure à la pression totale de l'air délivré par les compresseurs. Cette contre-pression augmente les pertes par pompage des moteurs fonctionnant selon un cycle à quatre temps et condamne les moteurs fonctionnant selon un cycle à deux temps.Nevertheless, the poor isentropic efficiency of very small turbomachines adapted to motor vehicle engines associated with the low temperature of the gases generated by the cold cycles, imply a total pressure of the gases at the inlet of the turbines greater than the total pressure of the air delivered by the compressors. This back pressure increases pumping losses of engines operating on a four-stroke cycle and condemns engines operating on a two-stroke cycle.
Un des buts de l'invention est de produire une forte suralimentation des moteurs à taux élevé de recyclage des gaz brûlés et à basse température d'échappement en limitant la contre-pression d'échappement nuisible au rendement de ce moteur. Un autre but de l'invention est d'éliminer les polluants générés par les cycles froids, essentiellement le monoxyde de carbone, les hydrocarbures imbrûlés et les particules générées par l'injection directe d'un carburant liquide.One of the aims of the invention is to produce a high supercharging of the high rate of recirculation engines of the flue gases and low exhaust temperature by limiting the exhaust backpressure detrimental to the efficiency of this engine. Another object of the invention is to eliminate the pollutants generated by the cold cycles, essentially carbon monoxide, unburnt hydrocarbons and particles generated by the direct injection of a liquid fuel.
L'invention a donc pour objet un moteur alternatif à combustion interne comprenant, d'une part, au moins un cylindre muni d'au moins une soupape d'admission et d'au moins une soupape d'échappement par laquelle est évacué un flux puisé de gaz brûlés dont la pression génératrice est la pression Pd régnant dans le cylindre à l'ouverture de ladite au moins soupape d'échappement et, d'autre part, un groupe de turbocompression actionné par lesdits gaz brûlés et d'alimentation dudit au moins cylindre en air comprimé refroidi, caractérisé en ce qu'au moins une partie du flux puisé de gaz brûlés est évacué dudit au moins cylindre par un conduit d'échappement muni d'une tuyère de détente débouchant tangentiellement à une paroi périphérique d'une chambre de centrifugation de révolution et perpendiculairement à l'axe de cette chambre et en ce que la chambre de centrifugation communique avec un conduit d'alimentation des turbines du groupe de turbocompression par un diffuseur radial annulaire coaxial à ladite chambre et ayant un diamètre d'entrée D, la pression statique dans la chambre de centrifugation étant maintenue à une valeur Ps inférieure à la pression Pd afin d'accélérer une fraction de gaz brûlés alimentant un anneau de gaz brûlés en mouvement de rotation rapide autour de l'axe de la chambre de centrifugation et qui s'évacue vers les turbines en se comprimant et en se ralentissant dans le diffuseur radial. Selon d'autres caractéristiques de l'invention :The subject of the invention is therefore an internal combustion internal combustion engine comprising, on the one hand, at least one cylinder provided with at least one intake valve and at least one exhaust valve through which a flow is evacuated. pulsed gas whose generating pressure is the pressure Pd prevailing in the cylinder at the opening of said at least one exhaust valve and, secondly, a turbocharging unit actuated by said burnt gas and said supply to less cylinder compressed air cooled, characterized in that at least a portion of the pulsed flow of burnt gas is discharged from said at least one cylinder by an exhaust pipe provided with an expansion nozzle opening tangentially to a peripheral wall of a bedroom revolution centrifugation and perpendicular to the axis of this chamber and in that the centrifugation chamber communicates with a turbocompressor group turbocharger supply duct by an annular radial diffuser coaxial with said chamber and having an inlet diameter D, the static pressure in the centrifuge chamber being maintained at a value Ps lower than the pressure Pd in order to accelerate a fraction of flue gases supplying a ring of burnt gases in rapid rotation movement about the axis of the chamber of centrifugation and which evacuates to the turbines by compressing and slowing down in the radial diffuser. According to other features of the invention:
- la chambre de centrifugation comporte un orifice axial de diamètre d inférieur au diamètre d'entrée D du diffuseur radial communiquant avec un conduit de recyclage des gaz brûlés et en ce que le volume d'un espace compris entre un cylindre fictif de diamètre D et un cylindre coaxial de diamètre d de longueurs égales à la distance entre l'orifice axial et l'entrée du diffuseur radial est, de préférence, supérieur à deux cylindrées unitaires du moteur,the centrifugation chamber comprises an axial orifice of diameter d smaller than the inlet diameter D of the radial diffuser communicating with a recycle line for the flue gases and in that the volume of a space comprised between a dummy cylinder of diameter D and a coaxial cylinder of diameter d of lengths equal to the distance between the axial orifice and the inlet of the radial diffuser is preferably greater than two unit cubic capacities of the engine,
- la chambre de centrifugation présente un volume supérieur à au moins trois fois la cylindrée unitaire du moteur afin d'y stabiliser la pressions statique quand l'orifice axial est fermé, - la chambre de centrifugation communique par l'orifice axial avec un volume au moins égal à trois cylindrées unitaires du moteur afin d'y stabiliser la pression statique,the centrifugation chamber has a volume greater than at least three times the unit cubic capacity of the motor in order to stabilize the static pressure when the axial orifice is closed; the centrifugation chamber communicates via the axial orifice with a volume at less than three engine unit displacements to stabilize the static pressure,
- la chambre de centrifugation communique avec le conduit de recyclage par l'orifice axial, la pression statique au niveau dudit orifice étant sensiblement égale à la pression d'admission du moteur,the centrifugation chamber communicates with the recycling duct via the axial orifice, the static pressure at said orifice being substantially equal to the intake pressure of the engine,
- l'orifice axial alimente un diffuseur radial annulaire ayant un diamètre d'entrée d, la pression statique au niveau dudit orifice axial étant inférieure à la pression d'admission du moteur,the axial orifice supplies an annular radial diffuser having an inlet diameter, the static pressure at said axial orifice being lower than the intake pressure of the engine;
- ladite au moins tuyère débouche dans ladite chambre de centrifugation au niveau d'un tronçon sensiblement conique s'étendant entre une zone de plus grand diamètre de cette chambre et ledit orifice axial de diamètre d, - la seconde soupape d'échappement est reliée par un conduit d'évacuation au conduit de recyclage en aval de l'orifice axial correspondant, la soupape d'échappement du second conduit s'ouvrant après la soupape d'échappement du premier conduit quand la pression dans le cylindre correspondant a suffisamment chuté,said at least one nozzle opens into said centrifugation chamber at a substantially conical section extending between a zone of greater diameter of said chamber and said axial orifice of diameter d, the second exhaust valve is connected by a discharge duct to the recycling duct downstream from the corresponding axial orifice, the exhaust valve of the second duct opening after the exhaust valve of the first duct when the pressure in the corresponding cylinder has dropped sufficiently,
- le moteur comporte entre le diffuseur radial annulaire du conduit d'alimentation des turbines du groupe de turbocompression et lesdites turbines, un filtre à particules à écoulement axial et, de préférence, cylindrique associé à des moyens d'élimination des particules déposées sur le filtre à particules, - les moyens d'élimination des particules comprennent un collecteur appliqué sur la face d'entrée du filtre à particules et déplaçable sur cette face pour balayer périodiquement la totalité de la surface de cette face, ledit collecteur communiquant avec une zone où la pression statique est inférieure à la pression en aval du filtre à particules pour créer un écoulement du gaz à contre- courant dans le secteur de ce filtre couvert par le collecteur,the motor comprises between the annular radial diffuser of the supply duct of the turbocharger group turbines and said turbines, an axial flow particle filter, preferably a cylindrical filter associated with means for removing the particles deposited on the filter; with particles, the means for removing the particles comprise a collector applied to the inlet face of the particle filter and movable on this face to periodically sweep the entire surface of this face, said collector communicating with an area where the static pressure is less than the pressure downstream of the particulate filter to create a flow of countercurrent gas in the sector of this filter covered by the manifold,
- le collecteur communique avec le conduit de recyclage pour brûler les particules extraites dudit filtre à particules dans ledit au moins cylindre,the collector communicates with the recycling duct to burn the particles extracted from said particulate filter in said at least cylinder,
- le collecteur communique avec une zone axiale de la chambre de centrifugation au voisinage du diffuseur radial du conduit d'alimentation des turbines, par une zone de combustion des particules située dans ladite chambre, etthe collector communicates with an axial zone of the centrifugation chamber in the vicinity of the radial diffuser of the turbine supply duct, by a combustion zone of the particles situated in said chamber, and
- le filtre à particules a la forme d'un cylindre de révolution dont les deux faces d'extrémité sont planes, ledit collecteur étant entraîné en rotation autour de l'axe de ce filtre. L'invention a également pour objet un procédé d'élimination des particules des gaz brûlés d'un moteur alternatif à combustion interne tel que précédemment mentionné, caractérisé en ce que :- The particle filter has the shape of a cylinder of revolution whose two end faces are flat, said collector being rotated about the axis of this filter. The subject of the invention is also a method for removing particles from the flue gases of an internal combustion reciprocating engine as previously mentioned, characterized in that:
- on fait passer les gaz brûlés évacués dans un filtre à particules à écoulement axial, et - on met périodiquement chaque secteur de la face d'entrée du filtre à particules en communication avec une zone où la pression statique est inférieure à la pression en aval de ce filtre à particules pour créer un écoulement des gaz à contre-courant dans chaque secteur dudit filtre à particules qui emporte les particules prélevées dans ledit filtre vers une zone où lesdites particules sont brûlées.the evacuated flue gases are passed through an axial flow particle filter, and each sector of the inlet face of the particulate filter is periodically brought into communication with an area where the static pressure is lower than the downstream pressure. of this particle filter to create a flow countercurrent gases in each sector of said particulate filter which carries particulates taken from said filter to an area where said particles are burned.
Selon d'autres caractéristiques du procédé : - la zone où la pression statique est inférieure à la pression en aval du filtre à particules est formée par un circuit de recyclage des gaz brûlés muni d'une vanne de réglage du débit de gaz recyclés, les particules prélevées étant brûlées dans ledit au moins cylindre du moteur,According to other characteristics of the process: the zone where the static pressure is lower than the pressure downstream of the particulate filter is formed by a flue gas recycling circuit provided with a valve for regulating the flow of recycled gas; particles removed being burned in said at least engine cylinder,
- la zone où la pression statique est inférieure à la pression en aval du filtre à particules est formée par une zone axiale d'une chambre de centrifugation,the zone where the static pressure is lower than the pressure downstream of the particulate filter is formed by an axial zone of a centrifugation chamber;
- la zone axiale communique avec le circuit de recyclage, les particules prélevées étant brûlées dans ledit au moins cylindre du moteur,the axial zone communicates with the recycling circuit, the particles removed being burned in the at least one cylinder of the engine,
- la zone axiale communique avec le groupe de turbocompres- sion, les particules prélevées étant brûlées dans la chambre de centrifugation.the axial zone communicates with the turbocharging unit, the particles removed being burned in the centrifugation chamber.
D'autres caractéristiques et avantages de l'invention apparaîtront au cours de la description qui va suivre et faite en référence aux dessins annexés, sur lesquels :Other features and advantages of the invention will become apparent from the description which follows and with reference to the appended drawings, in which:
- la Fig. 1 représente un schéma d'un exemple d'un ensemble d'évacuation des gaz brûlés et d'alimentation en comburant d'un moteur alternatif à combustion interne, conforme à l'invention,FIG. 1 is a diagram of an example of an assembly for exhausting burnt gases and supplying oxidant to an internal combustion reciprocating engine according to the invention,
- la Fig. 2 est une vue schématique à plus grande échelle et en coupe axiale d'une chambre de centrifugation du flux puisé de gaz brûlés émis par le moteur, - la Fig. 3 est une vue en coupe selon la ligne 3-3 de la Fig. 2,FIG. 2 is a diagrammatic view on a larger scale and in axial section of a centrifugation chamber of the pulsed flow of burnt gases emitted by the engine; FIG. 3 is a sectional view along the line 3-3 of FIG. 2
- les Figs. 4 et 5 sont des vues schématiques en coupe axiale de deux variantes de la chambre de centrifugation,- Figs. 4 and 5 are diagrammatic views in axial section of two variants of the centrifugation chamber,
- la Fig. 6 et 7 sont des vues schématiques respectivement en coupe axiale et selon la ligne 7-7 de la chambre de centrifugation associée à des moyens d'élimination des particules des gaz brûlés,FIG. 6 and 7 are diagrammatic views respectively in axial section and along the line 7-7 of the centrifugation chamber associated with means for removing particles from the flue gas,
- les Figs. 8 à 9 sont des vues schématiques en coupe axiale de deux variantes des moyens d'élimination des particules des gaz brûlés, - les Figs. 10 à 12 sont des schémas de plusieurs exemples de circuits d'évacuation des gaz brûlés et d'alimentation en comburant d'un moteur alternatif à combustion interne à quatre cylindres.- Figs. 8 to 9 are schematic views in axial section of two variants of the flue gas removal means, - Figs. Figures 10 to 12 are diagrams of several examples of flue gas discharge and oxidizer feed systems of a four-cylinder reciprocating internal combustion engine.
Sur la Fig. 1 , on a représenté schématiquement un moteur 1 qui comporte au moins un cylindre 1a muni d'au moins une soupape d'admission 2 et d'au moins une soupape d'échappement 3. Dans l'exemple de réalisation représenté sur cette figure, le cylindre 1a est pourvu d'une soupape d'admissionIn FIG. 1, schematically shows a motor 1 which comprises at least one cylinder 1a provided with at least one intake valve 2 and at least one exhaust valve 3. In the embodiment shown in this figure, the cylinder 1a is provided with an intake valve
2 et d'une soupape d'échappement 3.2 and an exhaust valve 3.
Le moteur 1 est associé à un ensemble de moyens qui sera décrit ultérieurement et qui permet de délivrer à ce moteur 1 un mélange d'air pur et de gaz brûlés dont la pression, la température et le taux de gaz recyclés sont réglables à chaque instant en fonction des paramètres de fonctionnement du moment.The engine 1 is associated with a set of means which will be described later and which allows to deliver to this engine 1 a mixture of clean air and burnt gases whose pressure, temperature and the rate of recycled gas are adjustable at any time depending on the operating parameters of the moment.
La soupape d'admission 2 est reliée à un collecteur d'admission 4 et la soupape d'échappement 3 est reliée à un conduit d'échappement 5 qui débouche dans une chambre centrifugation désignée par la référence générale 10. Cette chambre de centrifugation 10 transforme le flux puisé de gaz brûlés émis par le cylindre 1a du moteur 1 en deux écoulements, respectivement un flux désigné par Qt et un flux désigné par Qegr, à pressions sensiblement constantes. Le flux Qt est dirigé vers un groupe de turbocompression désigné dans son ensemble par la référence 30. Ce groupe de turbocompression 30 détend le flux Qt pour le rejeter à l'atmosphère et prend l'air atmosphérique désigné par Qair pour alimenter le cylindre 1a du moteur 1 par l'intermédiaire d'un conduit 6, d'un mélangeur 7 et du collecteur d'admission 4. Le groupe de turbocompression 30 est raccordé à la chambre de centrifugation 10 par un conduit 31.The intake valve 2 is connected to an intake manifold 4 and the exhaust valve 3 is connected to an exhaust duct 5 which opens into a centrifuge chamber designated by the general reference 10. This centrifuge chamber 10 transforms the pulsed flow of burnt gases emitted by the cylinder 1a of the engine 1 in two flows, respectively a flow designated by Qt and a flow designated by Qegr, at substantially constant pressures. The flow Qt is directed towards a turbocharger group generally designated by the reference 30. This turbocompression unit 30 relaxes the flow Qt to reject it to the atmosphere and takes the atmospheric air designated by Qair to feed the cylinder 1a of the motor 1 via a duct 6, a mixer 7 and the intake manifold 4. The turbocharger unit 30 is connected to the centrifugation chamber 10 via a duct 31.
Le flux d'air frais Qair est avantageusement comprimé, de manière classique, dans le groupe de turbocompression 30, par exemple une première fois par un turbocompresseur basse pression, puis est refroidi avant d'être comprimé une deuxième fois par un turbocompresseur haute pression et refroidi une seconde fois. Le flux Qt qui représente 50 à 70% du flux de gaz brûlés, égal au flux d'air frais Qair augmenté du débit de carburant brûlé est détendu successivement dans la turbine haute pression et la turbine basse pression avant d'être rejeté à l'atmosphère. En alternative, le flux Qt peut alimenter parallèlement la turbine haute pression et la turbine basse pression du groupe de turbocompression 30. Le flux Qegr, à la sortie de la chambre de centrifugation 10, est dirigé vers un circuit de recyclage qui comprend un conduit 35 reliant cette chambre de centrifugation 10 à une vanne distributrice 36 permettant de diriger le flux Qegr soit vers un réfrigérant 37, soit vers un conduit de dérivation 38. En aval de l'ensemble formé par la valve distributrice 36, le réfrigérant 37 et le conduit de dérivation 38, le circuit de recyclage comporte une vanne 39 de réglage du flux Qegr reliée au mélangeur 7 par une conduit 40. Le mélangeur 7 reçoit les flux Qair et Qegr pour alimenter le cylindre 1a du moteur 1 avec un mélange comburant homogène. Ainsi, le flux Qegr qui représente 30 à 50% du flux de gaz brûlés est refroidi sous pression et de façon réglable dans le réfrigérant 37, puis mélangé intimement au flux d'air frais Qair dans le mélangeur 7 pour alimenter le collecteur d'admission 4. Le réglage de la température du flux Qegr peut avantageusement s'effectuer en court-circuitant par la vanne distributrice 36 tout ou partie du flux circulant dans le réfrigérant 37.The fresh air flow Qair is advantageously compressed, in a conventional manner, in the turbocharger unit 30, for example a first time by a low pressure turbocharger, and is then cooled before being compressed a second time by a high-pressure turbocharger and cooled a second time. The Qt flow which represents 50 to 70% of the flue gas flow, equal to the fresh air flow Qair plus the burned fuel flow is successively relaxed in the high pressure turbine and the low pressure turbine before being released into the atmosphere. Alternatively, the flow Qt can feed the high-pressure turbine and the low-pressure turbine of the turbocharger unit 30 in parallel. The flow Qegr, at the outlet of the centrifugation chamber 10, is directed towards a recycling circuit which comprises a conduit 35. connecting this centrifugation chamber 10 to a distributor valve 36 for directing the flow Qegr either to a refrigerant 37 or to a bypass duct 38. Downstream of the assembly formed by the dispensing valve 36, the refrigerant 37 and the duct bypass 38, the recycling circuit comprises a flow control valve 39 Qegr connected to the mixer 7 by a conduit 40. The mixer 7 receives Qair flow and Qegr to supply the cylinder 1a of the engine 1 with a homogeneous combustion mixture. Thus, the flow Qegr which represents 30 to 50% of the flue gas stream is cooled under pressure and adjustably in the coolant 37, then intimately mixed with the flow of fresh air Qair in the mixer 7 to supply the intake manifold 4. The adjustment of the flow temperature Qegr can advantageously be carried out by short-circuiting by the distributor valve 36 all or part of the flow flowing in the coolant 37.
Le conduit 31 reliant la chambre de centrifugation 10 au groupe turbocompression peut être équipé d'un système de post-traitement désigné par la référence générale 50 et qui sera décrit ultérieurement.The conduit 31 connecting the centrifugation chamber 10 to the turbocharger unit may be equipped with a post-processing system designated by the general reference 50 and will be described later.
La limitation à 16000K environ de la température maximale du cycle de fonctionnement du moteur 1 entraîne une limitation proportionnelle de la température en fin de détente dans le cylindre 1a, disponible pour la turbocompression. Cette température étant fixée, la puissance des turbines du groupe de turbocompression 30 repose sur la pression totale du flux Qt. On voit donc l'intérêt d'exploiter de façon optimale la pression génératrice Pd disponible dans les gaz brûlés en fin de détente dans le cylindre 1a.The limitation to about 1600 ° K of the maximum temperature of the operating cycle of the engine 1 causes a proportional limitation of the temperature at the end of expansion in the cylinder 1a, available for turbocharging. As this temperature is set, the power of the turbines of the turbocharger unit 30 is based on the total pressure of the flow Qt. It is therefore seen that it is advantageous to exploit optimally the generating pressure Pd available in the exhaust gases at the end of expansion in the cylinder 1a.
Selon l'invention, la distribution et la circulation des flux de gaz dans la chambre de centrifugation 10 sont organisées de façon originale pour optimiser l'utilisation de cette pression dans le contexte mentionné ci-dessus. Tout d'abord, on rappelle certaines bases physiques du fonctionnement du moteur alternatif à combustion interne.According to the invention, the distribution and the circulation of the gas flows in the centrifugation chamber 10 are organized in an original way to optimize the use of this pressure in the context mentioned above. First of all, some physical bases of the operation of the reciprocating internal combustion engine are recalled.
En première approximation, la conservation de la masse pendant un cycle moteur en phase fermée impose la relation suivante entre les conditions dans le cylindre en début de compression et en fin de détente :As a first approximation, the conservation of the mass during a closed-cycle engine cycle imposes the following relationship between the conditions in the cylinder at the beginning of compression and at the end of expansion:
Pd/Pc = Vc/Vd x Td/Tc où Pd, Vd, Td et Pc, Vc, Tc sont respectivement la pression, le volume et la température des gaz en fin de détente et en début de compression.Pd / Pc = Vc / Vd x Td / Tc where Pd, Vd, Td and Pc, Vc, Tc are respectively the pressure, the volume and the temperature of the gases at the end of expansion and at the beginning of compression.
Pour un moteur dont les soupapes sont équipées d'un calage variable, Pd/Vc peut être réglé en jouant sur Vc/Vd à température d'admission constante. A calage fixe des soupapes, Pd/Pc peut être réglé en jouant sur la température d'admission. A fortiori, Pd/Pc peut être réglé en jouant sur les deux paramètres pour ajuster une autre variable du cycle, la température de compression Pc qui régit l'allumage, par exemple. Pour une pression d'admission donnée, la pression génératrice des gaz brûlés peut ainsi être réglée par des paramètres internes au moteur (calage des soupapes) ou par des paramètres externes (température d'admission).For a motor whose valves are equipped with variable timing, Pd / Vc can be set by playing Vc / Vd at constant inlet temperature. With fixed valve timing, Pd / Pc can be adjusted by adjusting the intake temperature. A fortiori, Pd / Pc can be adjusted by adjusting the two parameters to adjust another variable of the cycle, the compression temperature Pc which governs ignition, for example. For a given intake pressure, the pressure generating the flue gases can thus be adjusted by parameters internal to the engine (valve timing) or by external parameters (intake temperature).
Afin de faciliter la compréhension de la description qui suit, on choisi un exemple d'un moteur classique dont l'ouverture échappement et la fermeture admission se situent au voisinage du point mort bas du piston du cylindre 1a. Dans ces conditions : Vd = Vc et Pd/Pc = Td/Tc.In order to facilitate understanding of the following description, an example of a conventional engine is chosen whose exhaust opening and intake closure are in the vicinity of the bottom dead center of the piston of the cylinder 1a. Under these conditions: Vd = Vc and Pd / Pc = Td / Tc.
Pour une température d'admission de 325°K et une température d'échappement de 75O0K, Pd = 2Pc.For an inlet temperature of 325 ° K and an exhaust temperature of 75O 0 K, Pd = 2Pc.
La moitié des gaz brûlés présents dans le cylindre 1a peut, dans cet exemple de réalisation, être détendue à partir d'une pression génératrice supérieure à Pc, pression génératrice dont la moyenne massique se situe à 1 ,5 Pc.Half of the burnt gases present in the cylinder 1a can, in this embodiment, be expanded from a generating pressure greater than Pc, generating pressure whose mass average is 1, 5 Pc.
Pour un flux Qegr représentant 50% du flux d'échappement, une moitié des gaz chauds est destinée à être refroidi et transférée dans le collecteur d'admission 4 où la pression est voisine de Pc. L'autre moitié est destinée à être détendue dans les turbines du groupe de turbocompression 30 jusqu'à la pression atmosphérique. La chambre de centrifugation 10 est conçue pour orienter les gaz brûlés les plus énergétiques vers les turbines du groupe turbocompression 30 et les gaz les moins énergétiques vers le conduit de recyclage 35. En effet, le transfert du débit recyclé Qegr à partir de la chambre de centrifugation 10 vers le collecteur d'admission 4 peut s'effectuer à une pression voisine de Pc, si le conduit de recyclage est suffisamment dimensionné.For a flow Qegr representing 50% of the exhaust stream, one half of the hot gases is intended to be cooled and transferred into the intake manifold 4 where the pressure is close to Pc. The other half is intended to be expanded in turbines of the turbocharger unit to atmospheric pressure. The centrifuge chamber 10 is designed to direct the most energetic flue gases to the turbocharger turbines 30 and the least energy gases to the recycle conduit 35. In effect, the transfer of the recycled flow Qegr from the chamber centrifugation 10 to the intake manifold 4 can be carried out at a pressure close to Pc, if the recycling duct is sufficiently sized.
Le travail de refoulement des gaz recyclés du cylindre 1a est développé par le piston de ce cylindre dans le cas d'un moteur fonctionnant selon un cycle à quatre temps ou par la charge fraîche dans le cas d'un moteur fonctionnant selon un cycle à deux temps.The discharge work of the recycled gases of the cylinder 1a is developed by the piston of this cylinder in the case of an engine operating in a four-stroke cycle or by the fresh charge in the case of a motor operating in a two-cycle cycle. time.
Par contre l'énergie disponible dans le flux Qt de gaz brûlés est nécessaire pour réaliser les opérations suivantes :On the other hand, the energy available in the flue gas flow Qt is necessary to carry out the following operations:
- fournir dans les turbines du groupe de turbocompression 30 le travail absorbé par les compresseurs pour atteindre la pression d'admission Pad requise,supplying turbocompressor group turbines with the work absorbed by the compressors to reach the required inlet pressure Pad,
- générer la surpression nécessaire pour traverser le système de post-traitement 50,generate the overpressure necessary to cross the post-treatment system 50,
- créer une pression d'admission supérieure à la pression statique en aval du cylindre 1a pendant la phase de balayage dans le cas d'un moteur fonctionnant selon un cycle à deux temps.- Create an inlet pressure greater than the static pressure downstream of the cylinder 1a during the scanning phase in the case of a motor operating in a two-cycle cycle.
En se reportant maintenant aux Figs. 2 et 3, on va décrire un premier mode de réalisation de la chambre de centrifugation 10.Referring now to Figs. 2 and 3, a first embodiment of the centrifuge chamber 10 will be described.
Comme cela apparaît sur ces figures, la chambre de centrifugation 10 présente une forme générale de révolution d'axe XX. Dans l'exemple de réalisation représenté sur ces figures, la paroi périphérique 11 de cette chambre de révolution a la forme d'un cylindre.As it appears in these figures, the centrifugation chamber 10 has a general shape of revolution of axis XX. In the exemplary embodiment shown in these figures, the peripheral wall 11 of this chamber of revolution has the shape of a cylinder.
Le conduit d'échappement 5 mettant en communication la chambre du cylindre 1a lors de l'ouverture de la soupape d'échappement 3 avec la chambre de centrifugation 10, est pourvu à son extrémité libre d'une tuyère 12 de détente débouchant tangentiellement à la paroi 11 de cette chambre de centrifugation 10 et perpendiculairement à l'axe XX de ladite chambre de centrifugation. Ainsi, le flux puisé de gaz brûlés évacué du cylindre 1a à une pression Pd génératrice égale à la pression régnant dans le cylindre à l'ouverture de la soupape d'échappement 3 est détendu par la tuyère 12 qui débouche tangentiellement à la paroi périphérique 11 de la chambre de centrifugation 10 dans laquelle les pressions statiques sont maintenues sensiblement constantes. L'énergie potentielle des gaz est de ce fait partiellement transformée en énergie cinétique et stockée dans la masse gazeuse en rotation dans la chambre de centrifugation 10. La vitesse des gaz émise par la tuyère 12 décroît avec la pression génératrice de l'écoulement qui décroît entre la pression Pd et la pression statique qui règne dans la chambre de centrifugation 10 au débouché de la tuyère 12.The exhaust duct 5 placing the cylinder chamber 1a in communication with the centrifugal chamber 10 when opening the exhaust valve 3, is provided at its free end with a thrust nozzle 12 opening tangentially to the wall 11 of this centrifugation chamber 10 and perpendicular to the axis XX of said centrifuge chamber. Thus, the pulsed flow of burnt gases discharged from the cylinder 1a at a pressure Pd generative equal to the pressure prevailing in the cylinder at the opening of the exhaust valve 3 is expanded by the nozzle 12 which opens tangentially to the peripheral wall 11 of the centrifuge chamber 10 in which the static pressures are kept substantially constant. The potential energy of the gases is thus partially converted into kinetic energy and stored in the rotating gaseous mass in the centrifuge chamber 10. The velocity of the gases emitted by the nozzle 12 decreases with the pressure generating the flow which decreases. between the pressure Pd and the static pressure prevailing in the centrifugation chamber 10 at the outlet of the nozzle 12.
Au début de la détente, cette vitesse peut approcher la vitesse du son et décroît jusqu'à 0 quand les pressions s'égalisent.At the beginning of the relaxation, this speed can approach the speed of sound and decreases to 0 when the pressures equalize.
Le champ axisymétrique des pressions statiques dans la chambre de centrifugation 10 est régi par l'effet de centrifugation qui dépend lui même de l'évolution des vitesses tangentielles le long d'un rayon de cette chambre 10. Les gaz brûlés les plus rapides se placent donc naturellement vers la périphérie de la chambre de centrifugation 10 tandis que les gaz brûlés les plus lents se concentrent autour de l'axe XX de cette chambre 10. La pression statique et la pression totale diminuent simultanément entre la périphérie de la chambre de centrifugation 10 et son axe XX où la pression statique peut décroître largement au-dessous de la pression en début de compression Pc. La pression totale des gaz rapides est égale à la pression statique augmentée de la pression dynamique alors que la pression au débouché de la tuyère 12 est la pression statique diminuée de la pression dynamique.The axisymmetric field of the static pressures in the centrifugation chamber 10 is governed by the centrifugation effect which itself depends on the evolution of the tangential velocities along a radius of this chamber 10. The fastest burned gases are placed therefore naturally towards the periphery of the centrifuge chamber 10 while the slower burned gases are concentrated around the axis XX of this chamber 10. The static pressure and the total pressure decrease simultaneously between the periphery of the centrifuge chamber 10 and its axis XX where the static pressure can decrease significantly below the pressure at the beginning of compression Pc. The total pressure of the fast gases is equal to the static pressure increased by the dynamic pressure while the pressure at the outlet of the nozzle 12 is the static pressure minus the dynamic pressure.
La chambre de centrifugation 10 est dimensionnée pour limiter les pertes d'énergie cinétique par frottement de l'anneau gazeux contre les parois de cette chambre. Le temps de présence des gaz rapides dans la chambre de centrifugation 10 doit donc être minimal. Ainsi que montré à la Fig. 2, pour stabiliser les pressions statiques dans la chambre de centrifugation 10, cette chambre de centrifugation 10 est suffisamment grande ou selon la Fig. 5 communique par au moins un orifice axial 13 de diamètre d inférieur au plus grand diamètre de la chambre de centrifugation 10 avec un volume 14 communiquant avec le conduit de recyclage 35 et qui présente un grand volume par rapport à l'amplitude des pulsations. L'orifice 13 voit passer la respiration de la chambre 10 quand l'anneau C formé par les gaz brûlés rapides se gonfle et s'épuise aux rythmes des ouvertures et des fermetures de la soupape d'échappement 3.The centrifugation chamber 10 is dimensioned to limit the kinetic energy losses by friction of the gas ring against the walls of this chamber. The time of presence of the fast gases in the centrifuge chamber 10 must therefore be minimal. As shown in FIG. 2, to stabilize the static pressures in the centrifuge chamber 10, this centrifugation chamber 10 is sufficiently large or according to FIG. 5 communicates through at least one axial orifice 13 of diameter d less than the largest diameter of the centrifuge chamber 10 with a volume 14 communicating with the recycle conduit 35 and which has a large volume relative to the amplitude of the pulses. The orifice 13 sees the breathing of the chamber 10 when the ring C formed by the fast flue gas is inflated and depleted to the rhythms of the openings and closings of the exhaust valve 3.
Ainsi, les gaz rapides Qt sont rassemblés dans la zone torique de la chambre de centrifugation 10 sous la forme de l'anneau C et où le diamètre de cette chambre 10 est supérieur au diamètre d de l'orifice 13. Le volume de cette zone torique doit être supérieur à l'amplitude des pulsations volumiques des gaz rapides Qt et cette amplitude varie entre une et deux cylindrées unitaires pour un moteur à quatre temps et à quatre cylindres.Thus, the fast gases Qt are collected in the toric zone of the centrifugation chamber 10 in the form of the ring C and in which the diameter of this chamber 10 is greater than the diameter d of the orifice 13. The volume of this zone toric must be greater than the amplitude of the high-volume pulsations Qt fast and this amplitude varies between one and two cubic units for a four-stroke engine and four-cylinder.
La chambre de centrifugation 10 communique avec le conduit 31 d'alimentation des turbines du groupe de turbocompresseur 30 par un diffuseur radial annulaire 15 coaxial à ladite chambre 10 et ayant un diamètre minimum d'entrée D. Dans l'exemple de réalisation représenté à la Fig. 2, le diamètre d'entrée D du diffuseur radial 15 est égal au plus grand diamètre de la chambre de centrifugation 10. Dans le cas présent, la chambre de centrifugation 10 a un diamètre D sur toute sa longueur. Le diffuseur radial 15 prolonge donc extérieurement la zone torique de rassemblement des gaz rapides Qt dans la chambre de centrifugation 10 pour collecter et ralentir ces gaz rapides.The centrifugation chamber 10 communicates with the turbine feed duct 31 of the turbocharger unit 30 by an annular radial diffuser 15 coaxial with said chamber 10 and having a minimum inlet diameter D. In the exemplary embodiment shown in FIG. Fig. 2, the inlet diameter D of the radial diffuser 15 is equal to the largest diameter of the centrifuge chamber 10. In this case, the centrifuge chamber 10 has a diameter D along its entire length. The radial diffuser 15 thus extends externally the fast-gas collecting zone Qt in the centrifugation chamber 10 to collect and slow down these fast gases.
Ce diffuseur 15 est avantageusement formé par deux parois parallèles 16 et 17 s'étendant perpendiculairement à l'axe XX de la chambre de centrifugation 10 et délimitant entre elles un espace 18 de passage des gaz rapides Qt. Le débit de ces gaz rapides Qt qui traverse le diffuseur 15 est contrôlé par les turbines du groupe de turbocompresseur 30. Le débit du flux de gaz Qt est fonction de la largeur de l'espace 18, c'est à dire de la distance séparant les parois 16 et 17 du diffuseur radial 15, et de la section des turbines du groupe de turbocompression 30. La pression statique dans la chambre de centrifugation 10 est maintenue à une valeur Ps inférieure à la pression Pd afin d'accélérer une fraction des gaz brûlés alimentant l'anneau de gaz brûlés C en mouvement de rotation rapide autour de l'axe XX de la chambre de centrifugation 10 et qui s'évacue vers les turbines du groupe de turbocompression 30 en se comprimant et en se ralentissant dans le diffuseur radial 15.This diffuser 15 is advantageously formed by two parallel walls 16 and 17 extending perpendicularly to the axis XX of the centrifuge chamber 10 and delimiting therebetween a space 18 for the passage of fast gases Qt. The flow rate of these fast gases Qt which through the diffuser 15 is controlled by the turbines of the turbocharger group 30. The flow rate of the gas flow Qt is a function of the width of the space 18, that is to say the distance separating the walls 16 and 17 of the radial diffuser 15, and the turbine section of the turbocharger group 30. The static pressure in the centrifuge chamber 10 is maintained at a value Ps lower than the pressure Pd in order to accelerate a fraction of the flue gas supplying the ring of burnt gases. C in motion rapid rotation about the axis XX of the centrifuge chamber 10 and which escapes to the turbines of the turbocharger group 30 by compressing and slowing down in the radial diffuser 15.
Pour stabiliser la pression statique dans la chambre de centrifugation 10, deux solutions peuvent être envisagées. Pour la première solution, la chambre de centrifugation 10 présente un volume au moins égal à trois cylindrées unitaires. Dans ce cas, les gaz recyclés Qegr peuvent être recomprimés dans un diffuseur radial 20, comme cela sera décrit ultérieurement.To stabilize the static pressure in the centrifuge chamber 10, two solutions can be envisaged. For the first solution, the centrifugation chamber 10 has a volume at least equal to three cubic units. In this case, the recycled Qegr gases can be recompressed in a radial diffuser 20, as will be described later.
Pour la seconde solution, la chambre de centrifugation 10 présente un volume réduit pour limiter la surface mouillée par l'anneau gazeux en rotation rapide et elle communique par l'orifice 13 avec un volume 14 au moins égal à trois cylindrées unitaires.For the second solution, the centrifugation chamber 10 has a reduced volume to limit the wetted surface by the rapidly rotating gas ring and communicates through the orifice 13 with a volume 14 at least equal to three cubic units.
Selon une variante, l'entrée du diffuseur radial 15 peut avoir un diamètre D inférieur au diamètre maximal de la chambre de centrifugation 10. D'une manière générale, le volume d'un espace compris entre un cylindre fictif de diamètre D et un cylindre fictif coaxial de diamètre d de longueurs égales à la distance entre l'orifice 13 de diamètre d et l'entrée de diamètre D du diffuseur radial 15 est, de préférence, supérieur à deux cylindrées unitaires du moteur afin de maintenir la totalité des gaz rapides dans la chambre 10 pendant les respirations volumiques de l'anneau de gaz en rotation.According to one variant, the inlet of the radial diffuser 15 may have a diameter D less than the maximum diameter of the centrifugation chamber 10. In a general manner, the volume of a space between a dummy cylinder of diameter D and a cylinder Dummy coaxial of diameter d of lengths equal to the distance between the orifice 13 of diameter d and the diameter of inlet D of the radial diffuser 15 is preferably greater than two cubic units of the engine in order to maintain all the fast gases in the chamber 10 during the volume breaths of the rotating gas ring.
Après chaque fin de détente rapide, les gaz brûlés encore présents dans le cylindre 1a du moteur sont refoulés à basse vitesse par le piston dans le cas d'un moteur fonctionnant selon un cycle à quatre temps ou par la charge fraîche dans le cas d'un moteur fonctionnant selon un cycle à deux temps. Ces gaz lents doivent parvenir à la zone axiale de la chambre de centrifugation 10, en se mélangeant le moins possible aux gaz rapides.After each end of rapid expansion, the burnt gases still present in the cylinder 1a of the engine are discharged at low speed by the piston in the case of a motor operating in a four-stroke cycle or the fresh load in the case of an engine operating in a two-stroke cycle. These slow gases must reach the axial zone of the centrifugation chamber 10, mixing as little as possible with fast gases.
Ainsi que représenté à la Fig. 2, les gaz lents Qegr sont partiellement mélangés aux gaz rapides avant d'être ralentis par un diffuseur radial annulaire 20 qui met en communication la chambre de centrifugation 10 avec le conduit de recyclage 35. Ce diffuseur radial 20 a un diamètre minimum sensiblement égal au diamètre d de l'orifice de sortie 13. Le diffuseur radial 20 est formé de deux parois parallèles, respectivement 21 et 22, s'étendant perpendiculairement à l'axe XX de la chambre de centrifugation 10 et délimitant entre elles un espace 23 de passage des gaz lents Qegr.As shown in FIG. 2, the slow gases Qegr are partially mixed with the fast gases before being slowed down by an annular radial diffuser 20 which puts the centrifugation chamber 10 in communication with the recycling conduit 35. This radial diffuser 20 has a minimum diameter substantially equal to diameter d of the outlet orifice 13. The radial diffuser 20 is formed of two parallel walls, respectively 21 and 22, extending perpendicularly to the axis XX of the centrifuge chamber 10 and delimiting therebetween a gap 23 for passage of the slow gases Qegr.
La pression totale à l'entrée de ce diffuseur 20 est sensiblement au niveau de la pression d'admission Qad du moteur 1 et la pression statique dans ladite chambre 10 peut se situer au-dessous de cette pression d'admission Pad. Le diffuseur radial 20 élève la pression du flux de gaz lents Qegr au niveau de la pression d'admission dans le collecteur 4 du moteur 1. Le diffuseur radial 20 est facultatif dans le cas d'un moteur fonctionnant selon un cycle à quatre temps où le flux de gaz lents Qegr est pompé par le moteur. Par contre, il est nécessaire pour créer un flux de gaz lents Qegr dans un moteur fonctionnant selon un cycle à deux temps.The total pressure at the inlet of this diffuser 20 is substantially at the intake pressure Qad of the engine 1 and the static pressure in said chamber 10 may be below this inlet pressure Pad. The radial diffuser 20 raises the pressure of the slow gas flow Qegr at the intake pressure in the manifold 4 of the engine 1. The radial diffuser 20 is optional in the case of a motor operating in a four-cycle cycle where the slow gas flow Qegr is pumped by the engine. On the other hand, it is necessary to create a slow gas flow Qegr in a motor operating in a two-cycle cycle.
De préférence, chacun des diffuseurs 15 et 20 est lisse et le rapport de diamètres D/d de ces deux diffuseurs fixe le potentiel du flux de gaz lents Qegr. Le débit de gaz Qegr destiné à être recyclé dans le cylindre 1a est, de préférence et comme représenté à la Fig. 2, ralenti par le diffuseur radial 20 pour alimenter soit l'échangeur 4 refroidi par l'eau chaude de refroidissement du moteur 1 et qui est éventuellement suivi d'un second échangeur refroidi par un circuit d'eau à basse température, non représenté, ou soit le conduit de dérivation 38. La vanne de réglage 36 permet de moduler la fraction refroidie du flux de gaz Qegr et la vanne de recyclage 39 située en amont ou en aval de l'échangeur 37 permet de régler ce débit Qegr. Les gaz brûlés ainsi refroidis, les gaz brûlés passant par le conduit de dérivation 38 et l'air frais Qair sont mélangés intimement dans le mélangeur 7 avant de pénétrer dans le collecteur d'admission 4 et le cylindre 1a par la soupape d'admission 2.Preferably, each of the diffusers 15 and 20 is smooth and the ratio of diameters D / d of these two diffusers sets the potential of the slow gas flow Qegr. The flow rate of Qegr gas to be recycled in the cylinder 1a is preferably and as shown in FIG. 2, idle by the radial diffuser 20 to supply either the exchanger 4 cooled by the hot cooling water of the engine 1 and which is optionally followed by a second exchanger cooled by a low temperature water circuit, not shown, or the bypass duct 38. The control valve 36 modulates the cooled fraction of the Qegr gas flow and the recycling valve 39 located upstream or downstream of the exchanger 37 to adjust the flow Qegr. The burnt gases thus cooled, the flue gases passing through the bypass duct 38 and the fresh air Qair are intimately mixed in the mixer 7 before entering the intake manifold 4 and the cylinder 1a through the intake valve 2 .
Le vannage du débit de gaz recyclés Qegr est très efficace pour le fonctionnement du moteur en régime transitoire afin d'augmenter la quantité d'oxygène disponible pour la combustion de ce moteur. En effet, on augmente le débit de gaz Qt qui traverse les turbines du groupe de turbocompression 30 au détriment du débit de gaz recyclés Qegr remplacé instantanément par de l'air frais. Cette manoeuvre qui déplace les points de fractionnement dans les diagrammes caractéristiques des compresseurs s'effectue sans attendre l'accélération des turbines du groupe de turbocompression. En régime stabilisé, cette méthode consistant à augmenter le travail de pompage effectué par le piston n'est utilisée que pour des réglages fins. Généralement, on préfère le réglage du débit de gaz recyclés Qegr en modifiant le calage des soupapes ou en actionnant la vanne de réglage 36 de la température de Qegr. Dans le cas d'un moteur alternatif comportant une seule soupape d'échappement 3 par cylindre, les gaz lents empruntent le même conduit d'échappement 5 que les gaz rapides qui débouchent dans la chambre de centrifugation 10 par la tuyère de détente 12. La séparation de ces deux flux, c'est à dire le flux de gaz rapides et le flux de gaz lents s'effectue alors dans cette chambre de centrifugation 10.The Qegr Recycled Gas Flow Valve is very effective for transient engine operation to increase the amount of oxygen available for combustion of this engine. Indeed, it increases the Qt gas flow through the turbines turbocharger group 30 at the expense of recycled gas flow Qegr instantly replaced by fresh air. This maneuver, which moves the splitting points in the characteristic diagrams of the compressors, is done without waiting Turbocharger group turbocharging. In steady state, this method of increasing the pumping work done by the piston is used only for fine adjustments. Generally, it is preferred to adjust the flow of recycled Qegr gas by changing the valve timing or by operating the temperature control valve 36 of Qegr. In the case of an alternating engine comprising a single exhaust valve 3 per cylinder, the slow gases take the same exhaust duct 5 as the fast gases that open into the centrifuge chamber 10 via the expansion nozzle 12. separation of these two streams, ie the fast gas flow and the slow gas flow then takes place in this centrifuge chamber 10.
Pour limiter le mélange entre ces deux flux, la tuyère 12 débouche, ainsi que montré à la Fig. 4, dans une zone conique de la chambre de centrifugation 10 reliant une zone de grand diamètre à une zone de petit diamètre. Dans l'exemple de réalisation représenté sur cette figure 4, la paroi extérieure 11 de la chambre de centrifugation 10 forme un cône sur toute la longueur de cette chambre de centrifugation 10, la conicité de cette paroi étant dirigée vers l'orifice de sortie 13 de diamètre d.To limit the mixing between these two flows, the nozzle 12 opens, as shown in FIG. 4, in a conical zone of the centrifuge chamber 10 connecting a large diameter area to a small diameter area. In the exemplary embodiment shown in this FIG. 4, the outer wall 11 of the centrifugation chamber 10 forms a cone along the entire length of this centrifugation chamber 10, the conicity of this wall being directed towards the outlet orifice 13. of diameter d.
Compte tenu de cette conicité, les gaz issus de la tuyère de détente 12 s'orientent alternativement vers la zone de plus petit diamètre ou vers la zone de plus grand diamètre en fonction de leur vitesse d'éjection.Given this taper, the gases from the expansion nozzle 12 are oriented alternatively to the smaller diameter zone or to the larger diameter zone depending on their ejection speed.
Dans le cas d'une seule soupape d'échappement 3 par cylindre, la section de la tuyère 12 doit être suffisamment petite pour accélérer les gaz rapides et suffisamment grande pour ne pas freiner les gaz lents.In the case of a single exhaust valve 3 per cylinder, the section of the nozzle 12 must be small enough to accelerate the fast gases and large enough not to brake the slow gases.
Différentes géométries de la paroi extérieure 11 de la chambre de centrifugation 10 peuvent être envisagées. Le dimensionnement du conduit d'échappement 5 peut être choisi en fonction des buts recherchés. En effet, la masse de gaz immobilisée dans ce conduit 5 quand la soupape d'échappement 3 est fermée, est propulsée vers la chambre de centrifugation 10 par la détente des gaz du cycle suivant qui perdront de la quantité de mouvement. De plus, la colonne gazeuse ainsi accélérée dans le conduit 5 entraîne derrière elle par inertie une fraction des gaz peu énergétiques encore présents dans le cylindre 1a. Ce double échange de quantité de mouvements dégrade la différenciation énergétique entre le flux de gaz Qt et le flux de gaz Qegr.Different geometries of the outer wall 11 of the centrifuge chamber 10 can be envisaged. The dimensioning of the exhaust duct 5 can be chosen according to the desired goals. In fact, the mass of gas immobilized in this duct 5 when the exhaust valve 3 is closed, is propelled towards the centrifugation chamber 10 by the expansion of the gases of the next cycle which will lose momentum. In addition, the gaseous column thus accelerated in the conduit 5 entrains behind it by inertia a fraction of the low energy gases still present in the cylinder 1a. This double exchange of momentum degrades the energy differentiation between the Qt gas flow and the Qegr gas flow.
Pour optimiser la puissance des turbines du groupe de turbocompression 30, le volume du conduit 5 doit donc être minimal. Pour balayer un moteur à deux temps par effet d'inertie, le volume du conduit 5 est de préférence voisin de la cylindrée utilitaire du moteur.To optimize the power of the turbines of the turbocompression group 30, the volume of the conduit 5 must be minimal. To sweep a two-stroke engine by inertia effect, the volume of the duct 5 is preferably close to the engine capacity of the engine.
Dans le cas d'un moteur alternatif doté de deux soupapes d'échappement 3a et 3b par cylindre 1a, une soupape comme par exemple la soupape 3a, est affectée aux gaz rapides et une soupape, comme par exemple la soupape 3b, est affectée au gaz lents, ainsi que montré à la Fig. 5.In the case of an AC motor provided with two exhaust valves 3a and 3b per cylinder 1a, a valve such as valve 3a, for example, is assigned to fast gases and a valve, such as valve 3b, is assigned to slow gases, as shown in FIG. 5.
Les gaz rapides empruntent un conduit 5a équipé d'une tuyère de détente 12 et débouchant à la périphérie de la chambre de centrifugation 10, comme le conduit d'échappement 5 décrit précédemment, alors que les gaz lents empruntent un second conduit d'échappement 5b qui débouche en aval de l'orifice de sortie 13. Dans cet exemple de réalisation, le volume intérieur de la chambre de centrifugation 10 est séparé en deux volumes situés de part et d'autre de la cloison transversale 13a dans laquelle est ménagé l'orifice de sortie 13, un premier volume dans lequel sont dirigés les gaz rapides provenant de la soupape d'échappement 3a et un second volume dans lequel sont dirigés les gaz lents provenant de la soupape d'échappement 3b. L'orifice de sortie 13 voit alors passer un flux alternatif.The fast gases take a duct 5a equipped with an expansion nozzle 12 and opening out at the periphery of the centrifugation chamber 10, like the exhaust duct 5 described above, whereas the slow gases take a second exhaust duct 5b. which emerges downstream of the outlet orifice 13. In this embodiment, the internal volume of the centrifugation chamber 10 is separated into two volumes located on either side of the transverse partition 13a in which is formed the outlet port 13, a first volume in which are directed the fast gases from the exhaust valve 3a and a second volume in which are directed the slow gases from the exhaust valve 3b. The outlet orifice 13 then sees an alternating flow flow.
Dans ce mode de réalisation, la tuyère 12 alimentée exclusivement par des gaz rapides peut avoir une section inférieure à celle du précédent mode de réalisation. La soupape 3a du conduit d'échappement 5a s'ouvre la première et quand la pression dans le cylindre 1a a suffisamment chuté, la soupape d'échappement 3b du conduit 5b s'ouvre à son tour pour vidanger le cylindre 1a. Les deux soupapes 3a et 3b peuvent se fermer simultanément à la fin du transfert, la séparation des gaz en deux flux s'effectuant alors dans le cylindre 1a du moteur.In this embodiment, the nozzle 12 fed exclusively by fast gases may have a smaller section than the previous embodiment. The valve 3a of the exhaust duct 5a opens first and when the pressure in the cylinder 1a has dropped sufficiently, the exhaust valve 3b of the duct 5b opens in turn to drain the cylinder 1a. The two valves 3a and 3b can close simultaneously at the end of the transfer, the separation of gases in two flows then taking place in the cylinder 1a of the engine.
Dans un moteur alternatif fonctionnant selon un cycle à quatre temps, la quantité de gaz brûlés émis par le moteur est proportionnelle à son régime de fonctionnement. Le flux de gaz Qt est proportionnel à la section offerte aux gaz pour s'évacuer vers l'atmosphère, en l'occurrence la section d'un orifice équivalent aux turbines du groupe de turbocompression 30 ainsi qu'à la pression d'alimentation des turbines, elle même fonction du rendement du diffuseur radial 15.In an alternating engine operating on a four-stroke cycle, the quantity of burnt gases emitted by the engine is proportional to its operating regime. The flow of gas Qt is proportional to the section offered to the gases for venting to the atmosphere, in this case the section of an orifice equivalent to the turbines of the turbocharger unit 30 as well as the supply pressure of the turbocharger units. turbines, it itself depends on the efficiency of the radial diffuser 15.
Pour garantir la dépollution en oxyde d'azote à partir du régime minimal d'utilisation du moteur, il faut donc que la section minimale des turbines ne laisse passer que 60% environ du flux de gaz émis par le moteur à son régime minimal d'utilisation. Quand le moteur s'accélère, le rapport entre le débit de gaz Qt et le débit de gaz Qegr peut être réglé par le calage des soupapes du moteur, par la section des turbines du groupe de turbocompression, par la vanne de recyclage 39 ou par la vanne 36 qui règle la température du flux Qegr, comme mentionné dans la demande de brevet n° 03 03 728 également au nom du Demandeur. Selon une variante, le rapport Qt/Qegr peut aussi être réglé par la modification de la largeur de l'espace 18 ménagé entre les parois 16 et 17 du diffuseur radial 15 ou par la largeur de l'espace 23 ménagé entre les parois 21 et 22 du diffuseur radial 20.In order to guarantee the clearance of nitrogen oxide from the minimum operating speed of the engine, it is therefore necessary for the minimum turbine section to allow only about 60% of the flow of gas emitted by the engine to pass at its minimum speed. use. When the engine is accelerating, the ratio between the gas flow rate Qt and the gas flow rate Qegr can be adjusted by the engine valve timing, by the turbocharger group turbines section, by the recycling valve 39 or by the valve 36 which regulates the temperature of the flow Qegr, as mentioned in the patent application No. 03 03 728 also in the name of the Applicant. According to one variant, the ratio Qt / Qegr can also be adjusted by modifying the width of the space 18 formed between the walls 16 and 17 of the radial diffuser 15 or by the width of the space 23 formed between the walls 21 and 22 of the radial diffuser 20.
Selon une autre variante, la paroi 22 du diffuseur radial 2 peut être déplaçable par tout moyen de type approprié selon l'axe XX de la chambre de centrifugation 10 pour obturer l'orifice 13. Dans ce cas, la paroi mobile 22 remplace la vanne de recyclage 39.According to another variant, the wall 22 of the radial diffuser 2 may be displaceable by any appropriate type of means along the axis XX of the centrifugation chamber 10 to close the orifice 13. In this case, the movable wall 22 replaces the valve recycling 39.
Le travail développé par les turbines du groupe de turbocompression 30 augmente avec la température et la pression totale des gaz qui les alimentent. Pour une température donnée, le réglage de la puissance des turbines se fait donc essentiellement en jouant sur la pression totale du flux de gaz Qt en utilisant les actuateurs internes au moteur (calage des soupapes et de l'injection) et/ou les actuateurs externes (vanne 39 et/ou vanne 36 du circuit du flux de gaz Qegr). La pression totale du flux de gaz Qt est approximativement la somme de la pression statique régnant dans la chambre de centrifugation 10 et de la pression dynamique associée à la vitesse de rotation des gaz. Le rapport entre ces deux composants peut être choisi en réglant le niveau des pressions statiques dans cette chambre de centrifugation 10. Dans un moteur fonctionnant selon un cycle à quatre temps, ce réglage peut se faire par vannage du conduit de recyclage du flux de gaz Qegr. Quand on ferme la vanne de recyclage 39, la pression dynamique part d'une valeur maximale pour s'annuler quand le taux de détente dans la tuyère 12 est égal à l'unité.The work done by the turbocharger group turbines increases with the temperature and the total pressure of the gases that feed them. For a given temperature, the adjustment of the power of the turbines is done essentially by adjusting the total pressure of the gas flow Qt using the actuators internal to the engine (valve timing and injection) and / or the external actuators (valve 39 and / or valve 36 of the Qegr gas flow circuit). The total pressure of the gas flow Qt is approximately the sum of the static pressure prevailing in the centrifuge chamber 10 and the dynamic pressure associated with the speed of rotation of the gases. The report between these two components can be chosen by adjusting the level of the static pressures in this centrifugation chamber 10. In a motor operating in a four-cycle cycle, this adjustment can be done by throttling of the gas flow recycle line Qegr. When the recycle valve 39 is closed, the dynamic pressure starts from a maximum value to cancel when the expansion ratio in the nozzle 12 is equal to unity.
Le diffuseur radial annulaire 15 s'adapte automatiquement aux régimes aérodynamiques intermédiaires. En effet, pour une forte pression dynamique, l'écoulement de gaz Qt pénètre tangentiellement dans l'espace annulaire 18 pour y subir la diffusion. Pour une pression dynamique nulle, l'écoulement de gaz Qt traverse radialement le diffuseur 15 sans perte de charge.The annular radial diffuser 15 automatically adapts to intermediate aerodynamic speeds. Indeed, for a high dynamic pressure, the gas flow Qt penetrates tangentially into the annular space 18 to undergo diffusion. For a zero dynamic pressure, the gas flow Qt radially passes through the diffuser 15 without loss of load.
Selon une variante représentée sur les Figs. 6 à 9, le moteur alternatif à combustion interne est équipé de dispositifs de post-traitement 50 du flux de gaz Qt et qui sont situés entre le diffuseur radial annulaire 15 et l'entrée des turbines du groupe de turbocompression 30.According to a variant shown in Figs. 6 to 9, the reciprocating internal combustion engine is equipped with after-treatment devices 50 of the gas flow Qt and which are situated between the annular radial diffuser 15 and the turbine inlet of the turbocharger unit 30.
Ces dispositifs de post-traitement sont formés par un filtre à particules catalytiques 51 à écoulement axial et de préférence cylindrique. Le filtre 51 est traversé par le flux de gaz Qt à la sortie du diffuseur radial 15 dont la température est toujours supérieur à 4000C, température suffisante pour l'oxydation catalytique des hydrocarbures imbrûlés et du monoxyde de carbone, mais insuffisante pour brûler les particules déposées qui ne s'oxydent rapidement qu'au dessus de 6000C.These post-treatment devices are formed by a catalytic particle filter 51 with axial flow and preferably cylindrical. The filter 51 is traversed by the flow of Qt gas at the outlet of the radial diffuser 15 whose temperature is always greater than 400 0 C, sufficient temperature for the catalytic oxidation of unburned hydrocarbons and carbon monoxide, but insufficient to burn the deposited particles which oxidize rapidly only above 600 ° C.
Pour éliminer les particules déposées sur le milieu filtrant du filtre à particules 51 , un premier procédé consiste à laisser s'accumuler un certain poids de particules à l'entrée du filtre 51 et à brûler ces particules sur place en faisant monter périodiquement la température des gaz traversant le filtre à particules, par exemple en déchargeant à l'atmosphère une partie de l'air délivré par le compresseur haute pression. La régénération du filtre à particules 51 est d'autant plus rapide qu'elle est fréquente. Selon un second procédé, les particules lourdes centrifugées dans le diffuseur radial 15 sont concentrées sur une surface cylindrique 52 ménagée à la sortie du diffuseur radial 15 et en amont du filtre à particules 51 , par rapport au sens d'écoulement du flux de gaz Qt.In order to eliminate the particles deposited on the filtering medium of the particulate filter 51, a first method consists of allowing a certain weight of particles to accumulate at the inlet of the filter 51 and of burning these particles locally by periodically raising the temperature of the particles. gas passing through the particulate filter, for example by discharging into the atmosphere a portion of the air delivered by the high pressure compressor. The regeneration of the particulate filter 51 is all the more rapid as it is frequent. According to a second method, the heavy particles centrifuged in the radial diffuser 15 are concentrated on a cylindrical surface 52 arranged at the outlet of the radial diffuser 15 and upstream of the particle filter 51, with respect to the direction of flow of the gas flow Qt.
Selon un troisième procédé, une petite fraction du flux de gaz qui traverse le filtre à particules 51 , retraverse ce filtre 51 à contre-courant pour entraîner les particules vers une zone où elles seront brûlées. A cet effet et comme représenté sur les Figs. 6 à 9, le filtre à particules 51 est associé à des moyens d'élimination des particules qui comprennent un collecteur 55 appliqué sur la surface d'entrée 51a du filtre à particules 51. Le collecteur 55 est déplaçable sur cette face pour balayer périodiquement la totalité de la surface de la face 51a du filtre à particules 51.According to a third method, a small fraction of the gas flow that passes through the particulate filter 51, this filter 51 cross-flows to drive the particles to an area where they will be burned. For this purpose and as shown in Figs. 6 to 9, the particulate filter 51 is associated with particle removal means which comprises a manifold 55 applied to the inlet surface 51a of the particulate filter 51. The manifold 55 is movable on this face to periodically scan the the entire surface of the face 51a of the particulate filter 51.
Par ailleurs, le collecteur 55 communique avec une zone où la pression statique est inférieure à la pression en aval du filtre à particules 51 pour créer un écoulement de gaz à contre-courant dans le secteur du filtre 51 couvert par le collecteur 55. Le collecteur 55 est entraîné en rotation par un moyen 56 approprié, comme par exemple un moteur électrique 56 dont la vitesse est réglée pour assurer un cycle de nettoyage complet du filtre à particules 51 , par exemple toutes les secondes.On the other hand, the collector 55 communicates with an area where the static pressure is lower than the pressure downstream of the particulate filter 51 to create a countercurrent flow of gas in the sector of the filter 51 covered by the collector 55. The collector 55 is rotated by a suitable means 56, such as an electric motor 56 whose speed is adjusted to ensure a complete cleaning cycle of the particle filter 51, for example every second.
Comme représenté à la Fig. 6, le collecteur 55 est relié par un conduit 57 situé dans l'axe XX de la chambre de centrifugation 10 et qui débouche au niveau de l'orifice de sortie 13 où la pression statique est inférieure à la pression en aval du filtre à particule 51.As shown in FIG. 6, the collector 55 is connected by a duct 57 located in the axis XX of the centrifugation chamber 10 and which opens out at the outlet orifice 13 where the static pressure is lower than the pressure downstream of the particle filter 51.
Ainsi, une petite fraction du débit filtré retraverse le petit secteur du filtre à particules 51 couvert par le collecteur 55, à contre courant pour entraîner les particules qui viennent de s'y déposer vers l'extrémité du conduit 57. Les particules ainsi collectées peuvent être réintroduites dans le cylindre 1a avec les gaz recyclés pour y être brûlés. Le flux de balayage ainsi formé participe alors au débit du flux de gaz Qegr.Thus, a small fraction of the filtered flow returns the small sector of the particulate filter 51 covered by the collector 55, against the current to entrain the particles which have just deposited there towards the end of the conduit 57. The particles thus collected can to be reintroduced into the cylinder 1a with the recycled gases to be burned. The sweep flow thus formed then participates in the flow rate of the gas flow Qegr.
Si le flux de gaz ayant ainsi retraversé le filtre à particules 51 est suffisamment enrichi en particules, une zone 60 de combustion de ces particules peut être créée dans une zone axiale de la chambre de centrifugation 10, ainsi que montré à la Fig. 8. Le flux de gaz sans particule est alors évacué vers les turbines du groupe de turbocompression 30 en traversant le filtre à particules 51 et participe alors au débit de flux de gaz Qt. Le débit de ce flux de gaz sans particule peut être régulé par une accroche flamme 61 constitué par exemple par un cône afin de maintenir une richesse adéquate dans la zone de combustion 60.If the flow of gas having thus returned to the particle filter 51 is sufficiently enriched in particles, a zone 60 of combustion of these particles can be created in an axial zone of the centrifugation chamber 10, as shown in FIG. 8. The particle-free gas stream is then vented to the turbocharger group turbines 30 through the particulate filter 51 and then participates in the flow rate of gas Qt. The flow of this flow of gas without particle can be regulated by a flame catch 61 formed for example by a cone in order to maintain an adequate richness in the combustion zone 60.
Selon une variante représentée à la Fig. 9, un catalyseur d'oxydation 62 séparé du filtre à particules 51 peut être disposé entre le diffuseur radial 15 et ce filtre à particules 51. Dans ce cas, les particules solubles collantes sont brûlées dans le catalyseur d'oxydation 62 avant de pénétrer dans le filtre à particules 51 qui n'arrête que les particules sèches facilement entraînées par le flux de gaz recyclés par le collecteur 55. Les procédés d'élimination des particules précédemment mentionnés peuvent être utilisés séparément ou en combinaison.According to a variant shown in FIG. 9, an oxidation catalyst 62 separated from the particulate filter 51 may be disposed between the radial diffuser 15 and this particulate filter 51. In this case, the sticky soluble particles are burned in the oxidation catalyst 62 before entering the the particulate filter 51 which stops only the dry particles readily entrained by the recirculated gas stream from the manifold 55. The aforementioned particle removal methods can be used separately or in combination.
Sur les Figs. 10 à 12, on a représenté plusieurs exemples de configuration du circuit d'évacuation des gaz brûlés et du circuit d'alimentation en comburant d'un moteur alternatif à combustion interne à quatre cylindres. D'autres configurations peuvent bien évidemment être envisagées.In Figs. 10 to 12, there are shown several examples of configuration of the flue gas discharge circuit and the combustion circuit of a four-cylinder reciprocating internal combustion engine. Other configurations can of course be considered.
Sur ces figures, les éléments communs aux précédents modes de réalisation sont désignés par les mêmes références.In these figures, the elements common to the previous embodiments are designated by the same references.
Selon l'exemple de la Fig. 10, le moteur 1 comporte quatre cylindres 1a munis chacun d'une soupape d'admission 2 et d'une soupape d'échappement 3. La soupape d'échappement 3 de chaque cylindre 1a est reliée à un conduit d'échappement 5 qui débouche dans la chambre de centrifugation 10 de manière identique aux précédents modes de réalisation, c'est à dire par l'intermédiaire d'une tuyère de détente. Selon l'exemple de la Fig. 11 , le moteur 1 comporte quatre cylindres 1a munis chacun d'une soupape d'admission 2 et d'une soupape d'échappement 3. Dans ce cas, les soupapes d'échappement 3 de deux cylindres 1a contigus sont disposées côte à côte et sont reliées chacune par un conduit de liaison 5a au conduit d'échappement 5 qui débouche dans la chambre de centrifugation 10. Chaque conduit d'échappement 5 est équipé d'une tuyère disposée dans la chambre de centrifugation 10 de manière identique aux précédents modes de réalisation. Selon l'exemple de la Fig. 12, le moteur 1 comporte quatre cylindres 1a équipés chacun de deux soupapes d'admission, respectivement 2a et 2b, et de deux soupapes d'échappement respectivement 3a et 3b. Dans ce cas, les soupapes d'échappement 3a et 3b de deux cylindres 1a contigus sont disposées côte à côte.According to the example of FIG. 10, the engine 1 comprises four cylinders 1a each provided with an intake valve 2 and an exhaust valve 3. The exhaust valve 3 of each cylinder 1a is connected to an exhaust pipe 5 which opens in the centrifugation chamber 10 identically to the previous embodiments, that is to say via an expansion nozzle. According to the example of FIG. 11, the engine 1 has four cylinders 1a each provided with an intake valve 2 and an exhaust valve 3. In this case, the exhaust valves 3 of two cylinders 1a contiguous are arranged side by side and are each connected by a connecting duct 5a to the exhaust duct 5 which opens into the centrifugation chamber 10. Each exhaust duct 5 is equipped with a nozzle arranged in the centrifugation chamber 10 in a manner identical to the previous modes of centrifugation. production. According to the example of FIG. 12, the engine 1 comprises four cylinders 1a each equipped with two intake valves, respectively 2a and 2b, and two exhaust valves respectively 3a and 3b. In this case, the exhaust valves 3a and 3b of two cylinders 1a contiguous are arranged side by side.
La soupape d'échappement 3a de chaque cylindre 1a est affectée aux gaz rapides et la soupape 3b est affectée aux gaz lents.The exhaust valve 3a of each cylinder 1a is assigned to fast gases and the valve 3b is assigned to the slow gases.
Dans ce mode de réalisation, la soupape d'échappement 3a d'un cylindre 1a est reliée par un conduit de liaison 5a à la soupape d'échappement 3a du cylindre 1a contigu et cette soupape d'échappement 3a est raccordée au conduit d'échappement 5 muni d'une tuyère de faible section qui débouche dans la chambre de centrifugation 10 de manière identique aux précédents modes de réalisation.In this embodiment, the exhaust valve 3a of a cylinder 1a is connected by a connecting pipe 5a to the exhaust valve 3a of the adjoining cylinder 1a and this exhaust valve 3a is connected to the exhaust pipe 5 provided with a nozzle of small section which opens into the centrifuge chamber 10 in the same manner as the previous embodiments.
Les soupapes d'échappement 3b sont reliées entres elles par un conduit de recyclage 35 largement dimensionné à un ensemble désigné par A qui regroupe les éléments du circuit de recyclage des gaz Qegr ainsi que le mélangeur 7. Dans cet exemple de réalisation, le débit de gaz récupérés par le collecteur 55 est directement canalisé par le conduit 51 vers l'ensemble A pour être réaspiré par le moteur 1. Les soupapes 3a s'ouvrent d'abord pour faire chuter la pression dans les cylindres. Les soupapes 3b s'ouvrent ensuite pour le refoulement des gaz lents.The exhaust valves 3b are connected to each other by a recycling duct 35, which is largely dimensioned to an assembly designated by A which groups together the elements of the Qegr gas recycling circuit as well as the mixer 7. In this exemplary embodiment, the flow rate of gas recovered by the manifold 55 is directly channeled through the conduit 51 to the assembly A to be sucked by the engine 1. The valves 3a open first to reduce the pressure in the cylinders. Valves 3b then open for the discharge of slow gases.
L'invention est particulièrement avantageuse pour un cycle thermodynamique à taux élevé de recyclage des gaz brûlés (30 à 50% de la masse comburante) qui ne présente à aucun moment les conditions favorables à la formation des oxydes d'azote thermiques. Cette contrainte se résume à ne jamais dépasser une température locale de 19000K environ. La température maximale du cycle en chaque point de la chambre de combustion est la somme de la température locale en début de combustion Tcomb (température de compression) et de l'élévation de température due à la combustion (Tcomb). Cette température locale maximale dépend d'abord de paramètres internes aux moteurs tels que le taux de compression qui régit Tcomb, les concentrations locales de carburant et l'avance vers l'allumage qui régissent des Tcomb. Cette température dépend aussi des conditions d'admission telles que la composition chimique du mélange comburant qui régit la concentration d'oxygène, la température d'admission Tad qui régit Tcomb et la pression d'admission Pad qui régit la masse de gaz comburant à chauffer. La spécificité de ces cycles est une pression d'admission élevée pour introduire dans le cylindre des gaz brûlés qui s'ajoutent à l'air frais requis par la combustion et une basse température d'échappement résultant de la réduction de la température de combustion.The invention is particularly advantageous for a thermodynamic cycle with a high rate of recycling of flue gas (30 to 50% of the oxidizing mass) which at no time has the favorable conditions for the formation of thermal nitrogen oxides. This constraint boils down to never exceed a local temperature of 1900 0 K approximately. The maximum temperature of the cycle at each point of the combustion chamber is the sum of the local temperature at the start of combustion Tcomb (compression temperature) and the temperature rise due to combustion (Tcomb). This maximum local temperature depends primarily on internal engine parameters such as the compression ratio that governs Tcomb, the local fuel concentrations and the ignition advance that govern Tcomb. This temperature also depends on the admission conditions such as the chemical composition of the oxidizing mixture that governs the oxygen concentration, the Tad admission temperature that governs Tcomb and the intake pressure Pad that governs the mass of oxidizing gas to be heated. . The specificity of these cycles is a high inlet pressure to introduce into the cylinder burnt gases that add to the fresh air required by the combustion and a low exhaust temperature resulting from the reduction of the combustion temperature.
Le système de turbocompression doit donc fournir plus de travail avec moins d'énergie.The turbocharging system must therefore provide more work with less energy.
Ces cycles sont d'autant plus efficaces que l'on s'approche d'une combustion stoechiométrique. En effet, la puissance délivrée par une quantité d'air admise est proportionnelle à la fraction d'oxygène brûlé et le pouvoir de dilution des gaz recyclés augmente quand la concentration d'oxygène résiduelle diminue. En contre partie les cycles génèrent du monoxyde de carbone, des hydrocarbures imbrûlés et des particules dans le cas de l'injection directe.These cycles are all the more effective as one approaches a stoichiometric combustion. Indeed, the power delivered by a quantity of air admitted is proportional to the fraction of oxygen burned and the dilution power of the recycled gases increases when the residual oxygen concentration decreases. In contrast, the cycles generate carbon monoxide, unburned hydrocarbons and particles in the case of direct injection.
Le moteur alternatif à combustion interne selon l'invention évite ces inconvénients.The reciprocating internal combustion engine according to the invention avoids these disadvantages.
Le moteur alternatif selon l'invention présente l'avantage de rassembler dans un seul module sous pression les fonctionnements de turbocompression, de réfrigération, du post-traitement physique et chimique des gaz émis dans l'atmosphère, permettant ainsi de réduire sont coût.The reciprocating engine according to the invention has the advantage of collecting in a single pressurized module the operations of turbocompression, refrigeration, the physical and chemical post-treatment of the gases emitted into the atmosphere, thereby reducing its cost.
Le moteur alternatif selon l'invention permet aussi de neutraliser à la source les bruits d'échappement pour simplifier, voire éliminer le silencieux en aval des turbines du groupe de turbocompression The reciprocating engine according to the invention also makes it possible to neutralize exhaust noise at the source in order to simplify or even eliminate the silencer downstream of the turbocharger group turbines.

Claims

REVENDICATIONS
1. Moteur alternatif à combustion interne comprenant, d'une part, au moins un cylindre (1a) muni d'au moins une soupape d'admission (2) et d'au moins une soupape d'échappement (3) par laquelle est évacué un flux puisé de gaz brûlés dont la pression génératrice est la pression Pd régnant dans le cylindre (1a) à l'ouverture de ladite au moins soupape d'échappement (3) et, d'autre part, un groupe de turbocompression (30) actionné par lesdits gaz brûlés et d'alimentation dudit au moins cylindre (1a) en air comprimé refroidi, caractérisé en ce qu'au moins une partie du flux puisé de gaz brûlés est évacué dudit au moins cylindre (1a) par un conduit d'échappement (5) muni d'une tuyère de détente (12) débouchant tangentiellement à la paroi périphérique (11) d'une chambre de centrifugation (10) de révolution et perpendiculairement à l'axe de cette chambre(10) et en ce que la chambre de centrifugation (10) communique avec un conduit d'alimentation (31) des turbines du groupe de turbocompression (30) par un diffuseur radial annulaire (15) coaxial à ladite chambre (10) et ayant un diamètre d'entrée D, la pression statique dans la chambre de centrifugation (10) étant maintenue à une valeur Ps inférieure à la pression Pd afin d'accélérer une fraction de gaz brûlés alimentant un anneau de gaz brûlés en mouvement de rotation rapide autour de l'axe de la chambre de centrifugation (10) et qui s'évacue vers les turbines en se comprimant et en se ralentissant dans le diffuseur radial (15).A reciprocating internal combustion engine comprising, on the one hand, at least one cylinder (1a) provided with at least one intake valve (2) and at least one exhaust valve (3) through which discharged a pulsed flow of burnt gases whose generating pressure is the pressure Pd prevailing in the cylinder (1a) at the opening of the at least one exhaust valve (3) and, secondly, a turbocompression unit (30). ) actuated by said flue gas and supplying said at least one cylinder (1a) with cooled compressed air, characterized in that at least a portion of the pulsed flow of flue gas is discharged from said at least one cylinder (1a) through a duct exhaust (5) provided with an expansion nozzle (12) opening tangentially to the peripheral wall (11) of a centrifugal chamber (10) of revolution and perpendicular to the axis of this chamber (10) and in that the centrifugation chamber (10) communicates with a turbine supply duct (31) s of the turbocharger unit (30) by an annular radial diffuser (15) coaxial with said chamber (10) and having an inlet diameter D, the static pressure in the centrifuge chamber (10) being maintained at a lower value Ps at the pressure Pd in order to accelerate a fraction of burnt gases supplying a ring of burnt gases in rapid rotation movement about the axis of the centrifugation chamber (10) and which is evacuated towards the turbines by compressing itself and slowing down in the radial diffuser (15).
2. Moteur alternatif selon la revendication 1 , caractérisé en ce que la chambre de centrifugation (10) comporte un orifice axial (13) de diamètre d inférieur au diamètre d'entrée D du diffuseur radial (15) communiquant avec un conduit de recyclage (35) des gaz brûlés et en ce que le volume d'un espace compris entre un cylindre fictif de diamètre D et un cylindre coaxial de diamètre d de longueurs égales à la distance entre l'orifice axial (13) et l'entrée du diffuseur radial (15) est, de préférence, supérieur à deux cylindrées unitaires du moteur.2. Reciprocating engine according to claim 1, characterized in that the centrifugation chamber (10) comprises an axial orifice (13) of diameter d smaller than the inlet diameter D of the radial diffuser (15) communicating with a recycling duct ( 35) of the flue gases and in that the volume of a space between a dummy cylinder of diameter D and a coaxial cylinder of diameter d of lengths equal to the distance between the axial orifice (13) and the inlet of the diffuser radial (15) is preferably greater than two unit cubic units of the engine.
3. Moteur alternatif selon la revendication 1 , caractérisé en ce que la chambre de centrifugation (10) présente un volume supérieur à au moins trois fois la cylindrée unitaire du moteur afin d'y stabiliser la pressions statique quand l'orifice axial (13) est fermé. 3. Reciprocating engine according to claim 1, characterized in that the centrifugation chamber (10) has a volume greater than at least three times the unit cubic capacity of the engine in order to stabilize the static pressure when the axial orifice (13). is closed.
4. Moteur alternatif selon la revendication 1 , caractérisé en ce que la chambre de centrifugation (10) communique par l'orifice axial (13) avec un volume au moins égal à trois cylindrées unitaires du moteur afin d'y stabiliser la pression statique. 4. Reciprocating engine according to claim 1, characterized in that the centrifugation chamber (10) communicates through the axial orifice (13) with a volume at least equal to three cubic units of the engine in order to stabilize the static pressure.
5. Moteur alternatif selon l'une quelconque des revendications 2 à5. Reciprocating engine according to any one of claims 2 to
4, dans lequel le conduit de recyclage (35) des gaz brûlés prélève une partie du flux de gaz brûlés et la transfère sensiblement sans perte de charge vers un collecteur d'admission (4), la fraction restante du flux puisé de gaz brûlés alimentant les turbines du groupe de turbocompression (30), caractérisé en ce que la chambre de centrifugation (10) communique avec le conduit de recyclage (35) par l'orifice axial (13), la pression statique au niveau dudit orifice (13) étant sensiblement égale à la pression d'admission du moteur.4, in which the flue gas recycling duct (35) takes a portion of the flue gas stream and transfers it substantially without loss of pressure to an intake manifold (4), the remaining fraction of the pulsed flue gas stream supplying the turbocharger group turbines (30), characterized in that the centrifuge chamber (10) communicates with the recycle line (35) through the axial orifice (13), the static pressure at said orifice (13) being substantially equal to the engine intake pressure.
6. Moteur alternatif selon les revendications 2 et 5, caractérisé en ce que l'orifice axial (13) alimente un diffuseur radial annulaire (20) ayant un diamètre d'entrée d, la pression statique au niveau dudit orifice axial (13) étant inférieure à la pression d'admission du moteur.6. Reciprocating motor according to claims 2 and 5, characterized in that the axial orifice (13) feeds an annular radial diffuser (20) having an inlet diameter d, the static pressure at said axial orifice (13) being less than the engine intake pressure.
7. Moteur alternatif selon l'une quelconque des revendications 1 à 6, caractérisé en ce que ladite au moins tuyère (12) débouche dans ladite chambre de centrifugation (10) au niveau d'un tronçon sensiblement conique s'étendant entre une zone de plus grand diamètre de cette chambre (10) et ledit orifice axial (13) de diamètre d.7. Reciprocating engine according to any one of claims 1 to 6, characterized in that said at least one nozzle (12) opens into said centrifuge chamber (10) at a substantially conical section extending between a zone of larger diameter of this chamber (10) and said axial orifice (13) of diameter d.
8. Moteur alternatif selon l'une quelconque des revendications 1 à 5 ou 7, du type dans lequel ledit au moins cylindre (1a) est équipé d'une seconde soupape d'échappement (3b), caractérisé en ce que la seconde soupape d'échappement (3b) est reliée par un conduit d'évacuation (5b) au conduit de recyclage (35) en aval de l'orifice axial (13) correspondant, la soupape d'échappement (3b) du second conduit (5b) s'ouvrant après la soupape d'échappement (3a) du premier conduit (5a) quand la pression dans le cylindre (1a) correspondant a suffisamment chuté. 8. Reciprocating engine according to any one of claims 1 to 5 or 7, of the type in which the at least one cylinder (1a) is equipped with a second exhaust valve (3b), characterized in that the second valve of outlet (3b) is connected by a discharge duct (5b) to the recycling duct (35) downstream of the corresponding axial orifice (13), the exhaust valve (3b) of the second duct (5b) s opening after the exhaust valve (3a) of the first conduit (5a) when the pressure in the corresponding cylinder (1a) has dropped sufficiently.
9. Moteur alternatif selon l'une quelconque des revendications précédentes, caractérisé en ce qu'il comporte entre le diffuseur radial annulaire (15) du conduit d'alimentation (31) des turbines du groupe de turbocompression (30) et lesdites turbines, un filtre à particules (51) à écoulement axial et, de préférence, cylindrique associé à des moyens (55, 56, 57) d'élimination des particules déposées sur le filtre à particules (51).9. Reciprocating engine according to any one of the preceding claims, characterized in that it comprises between the annular radial diffuser (15) of the supply duct (31) turbines of the turbocharger group. (30) and said turbines, a particulate filter (51) with axial flow and, preferably, cylindrical associated with means (55, 56, 57) for removing particles deposited on the particulate filter (51).
10. Moteur alternatif selon la revendication 9, caractérisé en ce que les moyens d'élimination des particules comprennent un collecteur (55) appliqué sur la face d'entrée (51a) du filtre à particules (51 ) et déplaçable sur cette face pour balayer périodiquement la totalité de la surface de cette face, ledit collecteur (55) communiquant avec une zone où la pression statique est inférieure à la pression en aval du filtre à particules (51 ) pour créer un écoulement du gaz à contre-courant dans le secteur de ce filtre (51 ) couvert par le collecteur (55).An alternating motor according to claim 9, characterized in that the particle removal means comprises a manifold (55) applied to the inlet face (51a) of the particulate filter (51) and movable thereon to sweep. periodically the entire surface of this face, said collector (55) communicating with an area where the static pressure is less than the pressure downstream of the particulate filter (51) to create a flow of countercurrent gas in the sector of this filter (51) covered by the collector (55).
11. Moteur alternatif selon la revendication 10, caractérisé en ce que le collecteur (55) communique avec le conduit de recyclage (35) pour brûler les particules extraites dudit filtre à particules (51 ) dans ledit au moins cylindre (1 a).11. Reciprocating engine according to claim 10, characterized in that the collector (55) communicates with the recycle line (35) for burning particles extracted from said particulate filter (51) in said at least one cylinder (1 a).
12. Moteur alternatif selon la revendication 10, caractérisé en ce que le collecteur (55) communique avec une zone axiale de la chambre de centrifugation (10) au voisinage du diffuseur radial (15) du conduit d'alimentation12. AC motor according to claim 10, characterized in that the collector (55) communicates with an axial zone of the centrifugation chamber (10) in the vicinity of the radial diffuser (15) of the supply duct.
(31 ) des turbines, par une zone de combustion (60) des particules située dans ladite chambre (10).(31) turbines, by a combustion zone (60) of the particles located in said chamber (10).
13. Moteur alternatif selon l'une quelconque des revendications 10 à 12, caractérisé en ce que le filtre à particules (51) a la forme d'un cylindre de révolution dont les deux faces d'extrémité sont planes, ledit collecteur (55) étant entraîné en rotation autour de l'axe de ce filtre (51 ). 13. Reciprocating motor according to any one of claims 10 to 12, characterized in that the particle filter (51) has the shape of a cylinder of revolution whose two end faces are flat, said collector (55) being rotated around the axis of this filter (51).
14. Procédé d'élimination des particules des gaz brûlés rejetés à l'atmosphère par un moteur alternatif à combustion interne selon l'une quelconque des revendications précédentes, caractérisé en ce que :14. A method of removing particles from the flue gas discharged into the atmosphere by an internal combustion engine according to any one of the preceding claims, characterized in that:
- on fait passer les gaz brûlés évacués dans un filtre à particules (51 ) à écoulement axial, et - on met périodiquement chaque secteur de la face d'entrée du filtre à particules (51 ) en communication avec une zone où la pression statique est inférieure à la pression en aval de ce filtre à particules (51 ) pour créer un écoulement des gaz à contre-courant dans chaque secteur dudit filtre à particules (51 ) qui emporte les particules prélevées dans ledit filtre (51 ) vers une zone où lesdites particules sont brûlées.the evacuated flue gases are passed through an axial flow particle filter (51), and each sector of the inlet face of the particulate filter (51) is periodically brought into communication with an area where the static pressure is lower than the downstream pressure of this particulate filter (51) to create a countercurrent flow of gas in each sector of said particulate filter (51) which carries particles taken from said filter (51) to an area where said particles are burned.
15. Procédé selon la revendication 14, caractérisé en ce que la zone où la pression statique est inférieure à la pression en aval du filtre à particules (51 ) est formée par un circuit de recyclage (35, 36, 37, 38, 39, 40) des gaz brûlés muni d'une vanne de réglage (39) du débit de gaz recyclés, les particules prélevées étant brûlées dans ledit au moins cylindre (1a) du moteurMethod according to claim 14, characterized in that the zone where the static pressure is lower than the pressure downstream of the particulate filter (51) is formed by a recirculation circuit (35, 36, 37, 38, 39, 40) of the flue gases provided with a control valve (39) for the flow of recycled gas, the particles removed being burned in said at least cylinder (1a) of the engine
(1 )- 16. Procédé selon la revendication 14, caractérisé en ce que la zone où la pression statique est inférieure à la pression en aval du filtre à particules (51 ) est formée par une zone axiale d'une chambre de centrifugation (10).(1) - 16. The method according to claim 14, characterized in that the zone where the static pressure is lower than the pressure downstream of the particulate filter (51) is formed by an axial zone of a centrifugation chamber (10). ).
17. Procédé selon la revendication 16, caractérisé en ce que la zone axiale communique avec le circuit de recyclage (35, 36, 37, 38, 39, 40), les particules prélevées étant brûlées dans ledit au moins cylindre (1a) du moteur.17. A method according to claim 16, characterized in that the axial zone communicates with the recycling circuit (35, 36, 37, 38, 39, 40), the particles removed being burned in said at least cylinder (1a) of the engine .
18. Procédé selon la revendication 16, caractérisé en ce que la zone axiale communique avec le groupe de turbocompression (30), les particules prélevées étant brûlées dans la chambre de centrifugation (10). 18. The method of claim 16, characterized in that the axial zone communicates with the turbocompression group (30), the collected particles being burned in the centrifuge chamber (10).
EP06709199A 2005-02-04 2006-01-30 Reciprocating internal combustion engine and method of removing exhaust gas particles for one such engine Withdrawn EP1844218A1 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
FR0501156A FR2881793B1 (en) 2005-02-04 2005-02-04 INTERNAL COMBUSTION ALTERNATIVE MOTOR AND METHOD FOR REMOVING BURNER GAS PARTICLES FOR SUCH AN ALTERNATIVE ENGINE
PCT/FR2006/000203 WO2006082302A1 (en) 2005-02-04 2006-01-30 Reciprocating internal combustion engine and method of removing exhaust gas particles for one such engine

Publications (1)

Publication Number Publication Date
EP1844218A1 true EP1844218A1 (en) 2007-10-17

Family

ID=34955079

Family Applications (1)

Application Number Title Priority Date Filing Date
EP06709199A Withdrawn EP1844218A1 (en) 2005-02-04 2006-01-30 Reciprocating internal combustion engine and method of removing exhaust gas particles for one such engine

Country Status (4)

Country Link
US (1) US20080022980A1 (en)
EP (1) EP1844218A1 (en)
FR (1) FR2881793B1 (en)
WO (1) WO2006082302A1 (en)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN107002554A (en) * 2014-12-12 2017-08-01 博格华纳公司 It is controlled by the turbocharger turbine step valve of single actuator

Families Citing this family (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2909718B1 (en) * 2006-12-11 2009-02-27 Jean Melchior SUPERIOR INTERNAL COMBUSTION ENGINE
WO2009118471A1 (en) * 2008-02-29 2009-10-01 Melchior Jean-Frederic Pressure wave supercharged internal combustion engine
DE202008014030U1 (en) * 2008-10-21 2010-03-11 Mann+Hummel Gmbh Internal combustion engine with a turbocharger
US8109720B2 (en) * 2009-03-31 2012-02-07 General Electric Company Exhaust plenum for a turbine engine
KR20230061842A (en) * 2021-10-29 2023-05-09 현대자동차주식회사 Engine system

Family Cites Families (22)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3020903A (en) * 1957-12-06 1962-02-13 Kloeckner Humboldt Deutz Ag Air compressing fuel injection internal combustion engine
US3535850A (en) * 1966-10-28 1970-10-27 Hans J P Von Ohain Centrifugal particle separator
US3426513A (en) * 1967-11-13 1969-02-11 Kurt Bauer Vehicular vortex cyclone type air and gas purifying device
US3744251A (en) * 1972-05-01 1973-07-10 Philco Ford Corp Engine emission control device
US3890945A (en) * 1973-03-19 1975-06-24 Toyota Motor Co Ltd Exhaust gas cleaning system for internal combustion engines
JPS5137322A (en) * 1974-09-25 1976-03-29 Toyota Motor Co Ltd
US4345431A (en) * 1980-03-25 1982-08-24 Shimizu Construction Co. Ltd. Exhaust gas cleaning system for diesel engines
DE3012388A1 (en) * 1980-03-29 1981-10-08 Vereinigte Flugtechnische Werke Gmbh, 2800 Bremen GAS TURBINE
US4383411A (en) * 1981-08-10 1983-05-17 General Motors Corporation Diesel exhaust cleaner with burner vortex chamber
JPS6348930U (en) * 1986-09-17 1988-04-02
US4840028A (en) * 1987-03-20 1989-06-20 Matsushita Electric Industrial Co., Ltd. Purifier of diesel particulates in exhaust gas
DE3837472C2 (en) * 1988-11-04 1998-09-24 Deutz Ag Particulate filter system
DE3841182A1 (en) * 1988-12-07 1990-06-13 Bosch Gmbh Robert DEVICE FOR REMOVING SOLID PARTICLES, ESPECIALLY CARBON PARTICLES, FROM THE EXHAUST WASTE FROM COMBUSTION ENGINES
DE3941635A1 (en) * 1989-12-16 1991-06-20 Man Nutzfahrzeuge Ag METHOD FOR REGENERATING A SOOT FILTER OF A DIESEL INTERNAL COMBUSTION ENGINE, AND DEVICE FOR CARRYING OUT THIS METHOD
JPH0436008A (en) * 1990-05-30 1992-02-06 Hino Motors Ltd Backwash reproducing unit for particulate filter
DE4109227A1 (en) * 1991-03-21 1992-09-24 Schwaebische Huettenwerke Gmbh EXHAUST FILTER AND / OR CATALYST
DE4202960A1 (en) * 1992-02-01 1993-08-05 Ernst Apparatebau Gmbh & Co Soot filter with ring space
DK98993D0 (en) * 1993-09-01 1993-09-01 Per Stobbe DUST FILTER FOR HOT GASES
DE4415507C2 (en) * 1994-05-03 1997-02-13 Mtu Friedrichshafen Gmbh Particulate filter with filter element through which part of the surface flows
US6589306B2 (en) * 2001-07-18 2003-07-08 Ronning Engineering Co., Inc. Centrifugal separator apparatus for removing particulate material from an air stream
JP2003201826A (en) * 2002-01-09 2003-07-18 Nissan Diesel Motor Co Ltd Exhaust emission control device of diesel engine
FR2853011B1 (en) 2003-03-26 2006-08-04 Melchior Jean F ALTERNATIVE ENGINE FOR RECIRCULATING BURNED GASES FOR PROPULSION OF MOTOR VEHICLES AND METHOD OF TURBOCOMPRESSING THE SAME

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
See references of WO2006082302A1 *

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN107002554A (en) * 2014-12-12 2017-08-01 博格华纳公司 It is controlled by the turbocharger turbine step valve of single actuator
CN107002554B (en) * 2014-12-12 2019-10-22 博格华纳公司 It is controlled by the turbocharger turbine step valve of single actuator

Also Published As

Publication number Publication date
WO2006082302A1 (en) 2006-08-10
FR2881793A1 (en) 2006-08-11
US20080022980A1 (en) 2008-01-31
FR2881793B1 (en) 2007-05-11

Similar Documents

Publication Publication Date Title
FR2883601A1 (en) DEVICE FOR ACCELERATING A TURBOCOMPRESSION GROUP AT LOW REGIMES OF AN ALTERNATIVE MOTOR AND ALTERNATIVE MOTOR COMPRISING SUCH A DEVICE
EP0038232B1 (en) Method and system of power generation by an internal-combustion engine
EP1775441B1 (en) Supercharging device for an internal combustion engine and vehicle equipped with such a device
EP2129891B1 (en) Supercharged internal combustion engine
EP1844218A1 (en) Reciprocating internal combustion engine and method of removing exhaust gas particles for one such engine
WO2002090831A1 (en) Device and method for injecting a liquid fuel in an air flow for a combustion chamber
OA11186A (en) Method and device for recovering the ambient thermal energy for a vehicle equipped with a fresh-air engine with additional compressed air injection.
FR2853011A1 (en) ALTERNATIVE ENGINE FOR RECIRCULATING BURNED GASES FOR PROPULSION OF MOTOR VEHICLES AND METHOD OF TURBOCOMPRESSING THE SAME
EP2241742A1 (en) Double-stage supercharging system with device for purifying the exhaust gas for an internal combustion engine and method for controlling such a system
EP2414652B1 (en) Supercharged internal combustion engine
FR3107304A1 (en) CATALYTIC DEVICE FOR TREATMENT OF EXHAUST GASES FROM AN INTERNAL COMBUSTION ENGINE
WO2009118471A1 (en) Pressure wave supercharged internal combustion engine
FR3037357A1 (en) METHOD FOR HEATING AN EXHAUST SYSTEM OF AN INTERNAL COMBUSTION ENGINE ASSEMBLY BY AIR INJECTION
WO2005019618A1 (en) Supercharged engine comprising at least two turbocharger stages
FR2802241A1 (en) Malfunction detector for an internal exhaust gas system compares actual setting on valve connecting exhaust system to admission system with target setting obtained with new exhaust gas system
FR2752880A1 (en) Supercharger for motor vehicle IC-engine
FR2904056A1 (en) THERMAL MOTOR WITH MIXED RECIRCULATION CIRCUIT
WO2012150393A1 (en) Air supply circuit, turbocharged engine, and method for controlling the combustion of a turbocharged engine
EP2118464A2 (en) Reciprocating engine with burnt gas retention
FR2619854A1 (en) EXHAUST SYSTEM AND METHOD FOR INTERNAL COMBUSTION ENGINE, AND ENGINE PROVIDED WITH SUCH A SYSTEM
WO2001051786A1 (en) Method and device for improving the operation of supercharged internal combustion engines at low engine revs
EP1359309B1 (en) Gas turbine with a gas mixing device comprising lobes and pipes
FR2870566A1 (en) Device for treating exhaust gas from engines running on over-rich fuel, comprises turbocompressor, filter and catalytic unit, eliminates soot, unburnt fuel and nitrogen oxides
FR2799503A1 (en) Engine unit for turbocharged motor vehicle with an exhaust catalyzer, uses recirculation of exhaust gas into the combustion chambers to remove oxides of nitrogen, extracts exhaust before it reaches the turbocharger
WO2018046866A1 (en) System for recovering energy

Legal Events

Date Code Title Description
PUAI Public reference made under article 153(3) epc to a published international application that has entered the european phase

Free format text: ORIGINAL CODE: 0009012

17P Request for examination filed

Effective date: 20070711

AK Designated contracting states

Kind code of ref document: A1

Designated state(s): AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HU IE IS IT LI LT LU LV MC NL PL PT RO SE SI SK TR

DAX Request for extension of the european patent (deleted)
17Q First examination report despatched

Effective date: 20091111

STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: THE APPLICATION IS DEEMED TO BE WITHDRAWN

18D Application deemed to be withdrawn

Effective date: 20100323