WO1993010401A1 - Einrichtung zur unterdrückung von verbrennungsschwingungen in einer brennkammer einer gasturbinenanlage - Google Patents

Einrichtung zur unterdrückung von verbrennungsschwingungen in einer brennkammer einer gasturbinenanlage Download PDF

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Publication number
WO1993010401A1
WO1993010401A1 PCT/DE1992/000926 DE9200926W WO9310401A1 WO 1993010401 A1 WO1993010401 A1 WO 1993010401A1 DE 9200926 W DE9200926 W DE 9200926W WO 9310401 A1 WO9310401 A1 WO 9310401A1
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WO
WIPO (PCT)
Prior art keywords
combustion
feed line
vibrations
combustion chamber
acoustically
Prior art date
Application number
PCT/DE1992/000926
Other languages
German (de)
English (en)
French (fr)
Inventor
Bernhard Schetter
Original Assignee
Siemens Aktiengesellschaft
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 Siemens Aktiengesellschaft filed Critical Siemens Aktiengesellschaft
Priority to EP92922654A priority Critical patent/EP0611434A1/de
Priority to JP50886993A priority patent/JPH07501137A/ja
Priority to CZ941149A priority patent/CZ114994A3/cs
Publication of WO1993010401A1 publication Critical patent/WO1993010401A1/de

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Classifications

    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F23COMBUSTION APPARATUS; COMBUSTION PROCESSES
    • F23RGENERATING COMBUSTION PRODUCTS OF HIGH PRESSURE OR HIGH VELOCITY, e.g. GAS-TURBINE COMBUSTION CHAMBERS
    • F23R3/00Continuous combustion chambers using liquid or gaseous fuel
    • F23R3/28Continuous combustion chambers using liquid or gaseous fuel characterised by the fuel supply
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F23COMBUSTION APPARATUS; COMBUSTION PROCESSES
    • F23MCASINGS, LININGS, WALLS OR DOORS SPECIALLY ADAPTED FOR COMBUSTION CHAMBERS, e.g. FIREBRIDGES; DEVICES FOR DEFLECTING AIR, FLAMES OR COMBUSTION PRODUCTS IN COMBUSTION CHAMBERS; SAFETY ARRANGEMENTS SPECIALLY ADAPTED FOR COMBUSTION APPARATUS; DETAILS OF COMBUSTION CHAMBERS, NOT OTHERWISE PROVIDED FOR
    • F23M20/00Details of combustion chambers, not otherwise provided for, e.g. means for storing heat from flames
    • F23M20/005Noise absorbing means
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F23COMBUSTION APPARATUS; COMBUSTION PROCESSES
    • F23NREGULATING OR CONTROLLING COMBUSTION
    • F23N5/00Systems for controlling combustion
    • F23N5/16Systems for controlling combustion using noise-sensitive detectors
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F05INDEXING SCHEMES RELATING TO ENGINES OR PUMPS IN VARIOUS SUBCLASSES OF CLASSES F01-F04
    • F05DINDEXING SCHEME FOR ASPECTS RELATING TO NON-POSITIVE-DISPLACEMENT MACHINES OR ENGINES, GAS-TURBINES OR JET-PROPULSION PLANTS
    • F05D2220/00Application
    • F05D2220/30Application in turbines
    • F05D2220/32Application in turbines in gas turbines
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F05INDEXING SCHEMES RELATING TO ENGINES OR PUMPS IN VARIOUS SUBCLASSES OF CLASSES F01-F04
    • F05DINDEXING SCHEME FOR ASPECTS RELATING TO NON-POSITIVE-DISPLACEMENT MACHINES OR ENGINES, GAS-TURBINES OR JET-PROPULSION PLANTS
    • F05D2220/00Application
    • F05D2220/30Application in turbines
    • F05D2220/34Application in turbines in ram-air turbines ("RATS")
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F05INDEXING SCHEMES RELATING TO ENGINES OR PUMPS IN VARIOUS SUBCLASSES OF CLASSES F01-F04
    • F05DINDEXING SCHEME FOR ASPECTS RELATING TO NON-POSITIVE-DISPLACEMENT MACHINES OR ENGINES, GAS-TURBINES OR JET-PROPULSION PLANTS
    • F05D2260/00Function
    • F05D2260/96Preventing, counteracting or reducing vibration or noise
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F05INDEXING SCHEMES RELATING TO ENGINES OR PUMPS IN VARIOUS SUBCLASSES OF CLASSES F01-F04
    • F05DINDEXING SCHEME FOR ASPECTS RELATING TO NON-POSITIVE-DISPLACEMENT MACHINES OR ENGINES, GAS-TURBINES OR JET-PROPULSION PLANTS
    • F05D2260/00Function
    • F05D2260/96Preventing, counteracting or reducing vibration or noise
    • F05D2260/962Preventing, counteracting or reducing vibration or noise by means of "anti-noise"
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F05INDEXING SCHEMES RELATING TO ENGINES OR PUMPS IN VARIOUS SUBCLASSES OF CLASSES F01-F04
    • F05DINDEXING SCHEME FOR ASPECTS RELATING TO NON-POSITIVE-DISPLACEMENT MACHINES OR ENGINES, GAS-TURBINES OR JET-PROPULSION PLANTS
    • F05D2270/00Control
    • F05D2270/01Purpose of the control system
    • F05D2270/14Purpose of the control system to control thermoacoustic behaviour in the combustion chambers
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F23COMBUSTION APPARATUS; COMBUSTION PROCESSES
    • F23RGENERATING COMBUSTION PRODUCTS OF HIGH PRESSURE OR HIGH VELOCITY, e.g. GAS-TURBINE COMBUSTION CHAMBERS
    • F23R2900/00Special features of, or arrangements for continuous combustion chambers; Combustion processes therefor
    • F23R2900/00013Reducing thermo-acoustic vibrations by active means
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F23COMBUSTION APPARATUS; COMBUSTION PROCESSES
    • F23RGENERATING COMBUSTION PRODUCTS OF HIGH PRESSURE OR HIGH VELOCITY, e.g. GAS-TURBINE COMBUSTION CHAMBERS
    • F23R2900/00Special features of, or arrangements for continuous combustion chambers; Combustion processes therefor
    • F23R2900/00014Reducing thermo-acoustic vibrations by passive means, e.g. by Helmholtz resonators

Definitions

  • the invention relates to a device for suppressing combustion vibrations in a too acoustic
  • Vibration-capable combustion chamber of a gas turbine plant which combustion chamber has a burner for the combustion of a fluid carrying a fuel, which fluid can be fed to the burner through a feed line capable of acoustic vibrations and acoustically coupled to the combustion chamber.
  • Combustion chambers of gas turbine plants tend to self-excited combustion oscillations, depending on the operating state.
  • combustion vibrations have frequencies which correspond to the resonance frequencies of the combustion chamber or of another structure capable of vibration, including the combustion chamber; depending on the size of the vibratory structure, these frequencies are between a few Hz and several kHz, typically less than 1 kHz in gas turbine systems.
  • Pressure fluctuations of considerable magnitude are often associated with such combustion vibrations, in particular with amplitudes of the pressure up to the level of the steady pressure losses of the combustion chamber. Such pressure fluctuations can u. U. cause mechanical damage to the combustion chambers and other components of the gas turbine systems.
  • a combustion chamber for a gas turbine system with a burner arranged therein can be found in EP 0 193 838 B1.
  • the burner described there is a so-called “hybrid burner", a combination of diffusion burner and pre-burner. If the premix burner is operated, u. It may be necessary to support the combustion by means of an additional "pilot flame” from the diffusion burner.
  • Information on the design of a combustion chamber for a gas turbine system can be found in DE 25 23 449 C3.
  • the combustion chamber described there consists of a flame tube which is arranged in a housing, the air for combustion being fed through an annular gap between the flame tube and the housing to the burners arranged at one end of the flame tube.
  • the combustion air flows through the burners into the flame tube, fuel being added to it;
  • the combustion takes place in the flame tube.
  • the exhaust gases from the combustion are fed to the gas turbine, if necessary after admixing air.
  • Gas turbine plants which are operated with gaseous fuels are receiving increased attention in connection with coal gasification devices in which gaseous fuel is produced from coal.
  • Gas turbine plants in combination with coal gasification plants and steam power plants for waste heat recovery were dealt with in detail in a lecture by S. Joyce entitled “The Development of Integrated Coal-Gasification Combined-Cycle (ICG-GUD) Power Plants", presented on April 26th. 90 on the occasion of a seminar "Coal Gasification for Generation of Electricity" held in Arnhem (Netherlands); a transcript of the lecture was distributed during the seminar.
  • ICG-GUD Integrated Coal-Gasification Combined-Cycle
  • combustion vibrations With combustion vibrations conditions are acoustic vibrations, i.e. vibrations of the type of sound, which are ignited by transient combustion processes.
  • the frequency of a combustion oscillation is mainly determined by the geometry of the combustion chamber; the frequency of the combustion oscillation corresponds to a resonance frequency, which is defined by standing acoustic waves in the oscillatory structure to which the combustion chamber belongs.
  • Combustion vibrations often result from the fact that acoustic vibrations in a combustion chamber capable of acoustic vibrations cause acoustic vibrations in a feed line which is also capable of acoustic vibrations for the delivery of the fuel to the burner; the acoustic vibrations in the feed line, in turn, due to the pressure surges connected to them, cause an unsteady fuel flow to the burner and thus bring about an unsteady combustion, which in turn influences the acoustic vibrations in the combustion chamber.
  • a thermodynamic process can result on the burner, which releases mechanical energy from the combustion, which then flows into the acoustic vibrations in the combustion chamber.
  • the closed feedback circuit required for self-excitation which supplies the energy for the combustion vibrations, being formed by the acoustic transmission of vibrations from the combustion chamber into the feed line in connection with the thermodynamic transmission of vibrations from the feed line into the combustion chamber.
  • the described "acoustic coupling" between the combustion chamber and the feed line does not necessarily have to be a direct coupling between the gas columns in the combustion chamber and the feed line; this coupling can also be realized in that the wall of the combustion chamber is connected to the wall of the feed line, which allows the transmission of acoustic vibrations.
  • the acoustic coupling between the feed line and the combustion chamber is very complex and possibly implemented over several different transmission paths.
  • the acoustic coupling is a coupling that is also present in the absence of combustion and can therefore be determined, for example, by measurements on a combustion chamber arrangement through which no combustion flows.
  • the thermodynamic coupling between the feed line and the combustion chamber can also be measured, for example by filling the combustion chamber with acoustic insulation material, whereupon acoustic vibrations are measured in the combustion chamber, which are caused by the combustion by acoustic vibrations excited in the feed line.
  • combustion vibrations are understood to mean, above all, acoustic vibrations, the pressure amplitudes of which reach the order of magnitude of the pressure losses occurring in stationary operation above the combustion chambers, in particular exceeding sizes of about 10% of the respective pressure losses.
  • Usual pressure losses are approximately 200 kPa for aircraft engine gas turbines and approximately 50 kPa for power plant gas turbines. Tolerable acoustic vibrations should therefore not significantly exceed values of around 10 kPa.
  • the invention is based on the object of providing a device for suppressing combustion vibrations in a combustion chamber capable of acoustic vibrations
  • the device according to the invention for suppressing combustion vibrations in a combustion chamber of a gas turbine system capable of acoustic vibrations which combustion chamber has a burner for the combustion of a fluid carrying a fuel, which fluid is acoustically responsive to the burner by means of acoustic vibrations
  • the supply line coupled to the combustion chamber can be supplied, characterized by an acoustically active element coupled to the supply line, by means of which the supply line is acoustically tuned in such a way that unsteady combustion due to acoustic vibrations in the supply line is essentially ruled out.
  • acoustic vibrations in the feed line can mainly be understood as standing waves; this means that zones with vibrations of high amplitude and zones with vibrations of low or practically vanishing amplitude alternate in the feed line in accordance with the frequencies of the acoustic vibrations.
  • the arrangement of the standing waves in the feed line is influenced in such a way that a zone with a small, preferably essentially vanishing, amplitude comes to lie on the burner, which is an end of the feed line. Since the pressure conditions at the location of the burner directly determine the combustion, the guarantee of a sufficiently low pressure fluctuation in the supply line at the location of the burner leads to a sufficiently uniform, non-stationary combustion. Accordingly, the closed feedback circuit, in which self-excitation could build up, has broken down; The occurrence of combustion vibrations can thus be prevented efficiently.
  • the device according to the invention for suppressing combustion vibrations in a combustion chamber of a gas turbine system capable of acoustic vibrations which combustion chamber has a burner for the combustion of a fluid carrying a fuel, which fluid provides the burner with an acoustic signal
  • a feed line capable of vibrations and acoustically coupled to the combustion chamber can be fed, characterized by an acoustically active element coupled to the feed line, by means of which the feed line is acoustically tuned such that a reaction of acoustic vibrations in the feed line to acoustic vibrations in the combustion chamber, which reaction is caused by transient combustion due to the acoustic vibrations in the feed line device, counteracts the occurrence of combustion vibrations.
  • the invention is based on the fact that by adjusting the acoustic properties of the feed line, the phase position of the thermodynamically induced reaction can be influenced relative to the phase position of the acoustic coupling between the combustion chamber and the feed line;
  • the feed line is tuned by inserting a corresponding acoustically active element, so that the phase position of the thermodynamic reaction relative to the acoustic coupling does not correspond to a positive feedback required for self-excitation, but rather to a negative feedback.
  • the negative feedback precludes self-excitation and also results in "active acoustic damping" of the vibratory system, which includes the combustion chamber and the feed line.
  • the device of any design can be used in connection with any burner; it is particularly suitable for use in connection with a pre-burner which is part of a hybrid burner, for example. Reliable suppression of combustion vibrations in gas turbine plants in power plants with electrical power ratings up to 100 MW and above is possible.
  • the fuel can be a gas, for example natural gas or one obtained from a coal gasification process
  • the fluid carrying the fuel possibly being the gas itself.
  • the fuel can also be a solid or liquid substance, for example coal dust or oil, which is dispersed in a gas which is itself possibly combustible.
  • a liquid fuel e.g. B. oil, conceivable; oil-water emulsions and the like are also suitable.
  • the described measures for suppressing combustion vibrations also allow targeted upgrading of an already existing gas turbine system.
  • the design of the acoustically active element with regard to its acoustic parameters must be adapted to the properties of the predetermined combustion chamber and the location in the supply line to which it is to be coupled or connected.
  • the combustion vibrations occurring in the combustion chamber may have to be measured; in particular, acoustic waves in the feed line may also have to be examined.
  • the evaluation of such measurement data then leads to specific requirements for the acoustically active element to be coupled to the feed line.
  • the acoustic phenomena in the feed line of the burner are evaluated.
  • Helmholtz resonance nator As an acoustically effective element, there is a Helmholtz resonance nator in question; this consists of an essentially closed cavity or pot into which a piece of pipe or neck leads.
  • the mode of operation of the Helmhol tz resonator is known per se and therefore requires no detailed discussion at this point.
  • the Helmholtz resonator which is itself a structure capable of oscillation and has certain resonance frequencies, is not necessarily operated at such a resonance frequency in the present context.
  • a Helmholtz resonator can be designed in a particularly space-saving manner as a cavity coaxially surrounding the supply line in the manner of a muffler in the exhaust system of an internal combustion engine.
  • a further possibility for realizing the acoustically active element is the connection of a closed pipe section, that is to say a resonance pipe, to the feed line.
  • a closed pipe section that is to say a resonance pipe
  • Such resonance tubes are known as "quarter-wave tubes”.
  • the resonance tube is not necessarily operated at one of its resonance frequencies.
  • an acoustically effective element that is adjustable to change its acoustic properties.
  • Such an adjustable acoustically active element can be a Helmholtz resonator with a neck that is adjustable in length or a pot with variable volume; a resonance tube is also possible, which is closed with an adjustable slide and thus an adaptation of its acoustic properties to the requirements of the respective individual case allowed.
  • the use of adjustable acoustically active elements is to be preferred, since such elements allow adaptation to predetermined systems. It may also be appropriate to adjust the acoustically active element as a function of the operating state of the gas turbine system, since experience has shown that the occurrence of combustion vibrations depends relatively strongly on the respective load on the gas turbine system.
  • a further possibility for realizing the acoustically active element is to insert a cavity into the feed line, the cavity being an “open end” of the feed line in terms of acoustics.
  • the resonance behavior of the part of the supply line directly connected to the burner can be influenced in a targeted manner, so that combustion vibrations are effectively avoided.
  • the "acoustic effectiveness" of the cavity is not a specific "response behavior" to an acoustic wave that enters the cavity through the feed line, but simply the fact that an acoustic wave in a well-defined manner and practically completely at the mouth of the feed line in the cavity is reflected.
  • the part of the feed line between the burner and the cavity is thus acoustically decoupled from the other parts of the feed line; in terms of its acoustic properties, it is therefore easy to grasp theoretically and can be adapted to the respective requirements.
  • an acoustic termination in the manner of a "closed end" in a supply line would hardly be possible in a gas turbine system by means of a critically flowed orifice, which could be part of a throttle device, for example.
  • a critical flow acts as a reflector for Acoustic waves, since by definition sound waves flow through them and therefore wave propagation against the flowing flow is not possible. Ensuring such a "critical flow”, however, requires a considerable pressure drop across the orifice, which in connection with pressure-loaded combustion chambers would only be achievable with pressures at an impractical level in the feed lines. It should therefore be noted that in the context of the prior art in a gas turbine system, the formation of an acoustic termination in a fuel supply line was not practical.
  • An acoustically active element in the present sense can also be an acoustic transmitter coupled to the feed line, e.g. B. a speaker, a vibrating piston or a vibrating membrane.
  • Such an element is acted upon by an acoustic signal which is removed from the combustion chamber and which is characteristic of the acoustic conditions there.
  • Such an acoustic signal can, for example, by means of a transducer acoustically coupled to the combustion chamber, preferably directly to the flame tube, e.g. B. a microphone can be obtained.
  • the signal can be sent from the microphone to an amplifier via a signal line and from there to the acoustic transmitter via a further signal line.
  • the transmitter enables "active" suppression of combustion vibrations in addition to or instead of the "passive" suppression previously explained, the supply line being acted upon from the outside, to a certain extent forcibly, by an acoustic signal which counteracts the combustion vibrations.
  • suppression of the combustion vibrations can also be achieved, in particular when vibrations from the combustion chamber are coupled into the feed line only very little become; this is particularly so because, in addition to the coupling from the combustion chamber, an additional possibility for coupling vibrations into the feed line is used.
  • the suppression of combustion vibrations may be linked to the guarantee of certain phase relationships between acoustic vibrations in the combustion chamber and acoustic vibrations in the feed line.
  • a transmitter acted upon by an acoustic pickup is preferably used in connection with liquid fuel.
  • a particularly advantageous development of the device is characterized in that at least two acoustically active elements are provided in the feed line. It is particularly advantageous if an acoustically active element is a cavity, which represents an acoustically open end of the supply line, and a further acoustically active element is inserted between the cavity and the burner.
  • the cavity is used to acoustically close off a section of the feed line adjoining the burner and to decouple it from the rest of the feed line; the further acoustically active element can be used to tune the piece of the feed line thus obtained to suppress combustion vibrations.
  • the insertion of several acoustically active elements in a feed line means that several parameters are available for tuning the feed line, which can considerably simplify the suppression of combustion vibrations.
  • the suppression of combustion vibrations in a combustion chamber of a gas turbine system can be realized on the one hand with the aid of the acoustically active element coupled to the feed line in such a way that acoustic vibrations in the feed line, which can lead to in-stationary combustion, are largely suppressed. Under certain circumstances this amounts to avoiding resonance frequencies in the feed line which correspond approximately to the resonance frequencies of the combustion chamber.
  • the suppression of combustion vibrations in the combustion chamber can also be carried out by explicitly accepting vibrations in the feed line are set in that the acoustic properties of the feed line are set by the acoustically active element in such a way that a vibration excited in the feed line counteracts the combustion vibration in the combustion chamber.
  • This measure assumes that an oscillation in the feed line which is stimulated by an oscillation in the combustion chamber must also have a certain phase relationship to the combustion oscillation.
  • the mutual coupling of the vibrations mentioned can be influenced in such a way that the vibrations do not support each other, but counteract each other. This adjustment of the phase relationship between the vibrations must take into account the dynamics of the combustion process.
  • combustion of a fuel emerging from a burner occurs only after a certain time delay and, moreover, takes up a certain period of time.
  • the phase relationship between combustion oscillation and oscillation in the feed line must be dimensioned taking this delay into account.
  • FIG. 1 shows a combustion chamber with feed lines for fuel, supplemented by a device for suppressing combustion vibrations
  • FIGS. 2 and 3 show exemplary embodiments of an acoustically effective element in a feed line
  • Fig. 4 and Fig. 5 embodiments of an adjustable or controllable acoustically active element in one Supply line.
  • combustion chamber 1 shows a combustion chamber 1, which can optionally be used as one of several in a (not shown) gas turbine system, with two burners 2, each of which can be supplied with a gas carrying a fuel through a feed line 3. It is assumed that the combustion chamber 1 and the feed lines 3 are capable of acoustic vibrations, as is generally the case with components of gas turbine systems. Important for this is in particular the fact that supply lines 3 and combustion chambers 1 of gas turbine systems are usually not manufactured or filled with acoustically insulating substances, since such substances increase the pressure losses caused in the combustion chambers 1 or supply lines 3, which is always very disadvantageous for the efficiency of the gas turbine system is.
  • the combustion chamber 1 is formed from a flame tube 8 with a bottom 9 into which the burners 2 are let in; the flame tube 8 is — essentially concentrically — surrounded by an outer tube 10.
  • Combustion air can flow between the flame tube 8 and the outer tube 10 from a compressor of the gas turbine system to the burners 2.
  • the combustion air is mixed with fuel in the burners 2; the combustion essentially takes place in the flame tube 8, from which the combustion gases subsequently flow to a gas turbine of the gas turbine system.
  • the burners 2 are so-called premix burners.
  • the gas carrying the fuel is supplied to the combustion air through main nozzles 11, mixed intensively with it in a blading 12 and ignited only when it enters the flame tube 8.
  • auxiliary nozzle 13 which has a certain proportion of fuel is introduced directly into the flame tube 8, where it burns in a diffusion flame and thus provides a "pilot flame” for stabilizing the premix combustion.
  • the lower feed line 3 has a laterally connected Helmholtz resonator 4 as an acoustically active element.
  • a Helmholtz resonator 5 arranged coaxially around it is provided on the upper feed line 3.
  • Essential elements of each Helmholtz resonator 4, 5 are a neck 14, i. H. a narrow piece of pipe, and a pot 15, d. H. a relatively large cavity that connects to the neck 14.
  • the mode of operation of the Helmholtz resonator 4, 5 has already been explained.
  • a control valve 16 is inserted into each feed line 3; Both control valves 16 can be controlled via a branching control line 17 and thus allow, if necessary in conjunction with further measures, an adjustment of the thermal power generated in the combustion chamber 1 and a power control of the gas turbine system. Under certain circumstances, the control valves 16 (or similar components) can represent acoustic closings of the feed lines 3; this is the case if there is a noticeable amount of pressure loss.
  • the insertion of throttling points in supply lines 3 is common and advantageous if these supply lines 3 are supplied with fuel by a common delivery device. As a rule, throttling points in the feed lines 3 serve to even out the distribution of the fuel on these feed lines 3.
  • a resonance tube 6 is coupled to the feed line 3.
  • One end of the resonance tube 6 opens into the feed line 3; the other end facing away from the feed line 3 is closed.
  • An acoustic vibration excited in the feed line 3 is coupled into the resonance tube 6; the acoustic behavior of the resonance tube 6 influences the acoustic properties of the feed line 3.
  • the resonance tube 6 can be used in particular to set the resonance frequency for the structure of the feed line 3 and the resonance tube 6.
  • a large-volume cavity 7 is inserted into the feed line 3.
  • This cavity 7 represents an acoustically open end of the feed line 3; it uncouples the piece of the feed line 3 between itself and the burner 2 (not shown) from the piece of the feed line 3 leading from it to the conveying device.
  • the cavity 7 By suitably positioning the cavity 7, the acoustic properties of the feed line 3 between the burner 2 and the cavity 7 matched so that the combustion vibrations are suppressed.
  • FIG. 4 shows, similar to FIG. 2, a resonance tube 6 coupled to the feed line 3 as an acoustically active element. 4, the resonance tube 6 is closed at the end by means of a movable slide 18 which allows the acoustic properties of the resonance tube 6 to be adjusted (for example its resonance frequencies). By adjusting the slide 18, the resonance tube 6 can be adapted to different operating states of the combustion chamber 1 to which the feed line 3 is connected. This is in particular against the endeavor to be able to operate a gas turbine plant safely over the largest possible power range.
  • Fig. 5 shows a possibility of realizing the acoustically active element by means of an acoustic transmitter, namely a loudspeaker 19, which in one Housing 20 is coupled or attached to the feed line 3 and is acted upon by an acoustic signal removed from the flame tube 8.
  • This signal is taken from the flame tube 8 by means of a microphone 21 and fed to the amplifier 23 via a signal line 22, and to the loudspeaker 19 via a further signal line 24.
  • the phase of the acoustic in the feed line 3 caused by the loudspeaker 19 is adjusted Vibration may include amplifier 23, for example, a setting element 25, shown as a capacitor with variable capacitance, for adjusting the phase of its output signal. Possibly.
  • the correct phase relationship can be achieved by appropriate selection of the position of the microphone 21 on the flame tube 8.
  • several, z. B. two, acoustically effective elements 7, 19 may be provided.
  • the combination of a large cavity 7, as shown in FIG. 5, with another acoustically active element 19 is particularly preferred.
  • the cavity 7 serves the piece of the feed line 3 between the
  • the loudspeaker 19 is connected between the burner 2 and the cavity 7.
  • the mode of operation of the acoustically active elements 4, 5, 6, 7, 19 shown in the drawing can be used in accordance with each embodiment of the invention, since both versions can be implemented essentially using the same structural measures.
  • the mode of operation of the acoustically active element 4, 5, 6, 7, 19 depends on its design and coordination, under certain circumstances, not only the position of a single resonance frequency, but also the arrangement of a plurality or a plurality of resonance frequencies and any other acoustic properties.
  • its damping properties can also be important, which can be particularly important and advantageous if the acoustically active element does not directly flow through the feed line 3
  • the invention enables the suppression of combustion vibrations in a combustion chamber of a gas turbine system in a simple and safe manner.
  • the device according to the invention is easily adaptable to the requirements of the individual case and enables safe and reliable operation of the gas turbine system.

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  • Engineering & Computer Science (AREA)
  • Chemical & Material Sciences (AREA)
  • Combustion & Propulsion (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
PCT/DE1992/000926 1991-11-15 1992-11-06 Einrichtung zur unterdrückung von verbrennungsschwingungen in einer brennkammer einer gasturbinenanlage WO1993010401A1 (de)

Priority Applications (3)

Application Number Priority Date Filing Date Title
EP92922654A EP0611434A1 (de) 1991-11-15 1992-11-06 Einrichtung zur unterdrückung von verbrennungsschwingungen in einer brennkammer einer gasturbinenanlage
JP50886993A JPH07501137A (ja) 1991-11-15 1992-11-06 ガスタービン設備の燃焼室内の燃焼振動抑制装置
CZ941149A CZ114994A3 (en) 1991-11-15 1992-11-06 Device for suppressing vibrations induced by combustion within a combustion chamber

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
DEP4137672.2 1991-11-15
DE4137672 1991-11-15

Publications (1)

Publication Number Publication Date
WO1993010401A1 true WO1993010401A1 (de) 1993-05-27

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PCT/DE1992/000926 WO1993010401A1 (de) 1991-11-15 1992-11-06 Einrichtung zur unterdrückung von verbrennungsschwingungen in einer brennkammer einer gasturbinenanlage

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EP (1) EP0611434A1 (ja)
JP (1) JPH07501137A (ja)
CZ (1) CZ114994A3 (ja)
WO (1) WO1993010401A1 (ja)

Cited By (33)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE4339094A1 (de) * 1993-11-16 1995-05-18 Abb Management Ag Verfahren zur Dämpfung von thermoakustischen Schwingungen sowie Vorrichtung zur Durchführung des Verfahrens
GB2288660A (en) * 1994-04-23 1995-10-25 Abb Management Ag Apparatus for damping thermoacoustic vibrations in combustion chamber
EP0730122A1 (fr) * 1995-03-02 1996-09-04 Chaffoteaux Et Maury Brûleur à gaz présentant une discrétion acoustique améliorée
WO1998012478A1 (de) 1996-09-16 1998-03-26 Siemens Aktiengesellschaft Verfahren und einrichtung zur verbrennung von brennstoff mit luft
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EP0985810A1 (de) * 1998-09-10 2000-03-15 Abb Research Ltd. Verfahren und Vorrichtung zum Minimieren thermoakustischer Schwingungen in Gasturbinenbrennkammern
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EP1010939A1 (de) * 1998-12-15 2000-06-21 ABB Alstom Power (Schweiz) AG Brennkammer mit akustisch gedämpftem Brennstoffversorgungssystem
EP1004823A3 (de) * 1998-11-10 2000-11-29 Asea Brown Boveri AG Dämpfungsvorrichtung zur Reduzierung der Schwingungsamplitude akustischer Wellen für einen Brenner
DE19948674A1 (de) * 1999-10-08 2001-04-12 Abb Schweiz Ag Verbrennungseinrichtung, insbesondere für den Antrieb von Gasturbinen
EP0926325A3 (en) * 1997-12-23 2001-04-25 United Technologies Corporation Apparatus for use with a liquid fuelled combustor
EP1223381A2 (de) * 2001-01-10 2002-07-17 Robert Bosch Gmbh Verfahren zum Betrieb einer Gastherme
WO2003023281A1 (de) * 2001-09-07 2003-03-20 Alstom Technology Ltd Dämpfungsanordnung zur reduzierung von brennkammerpulsationen in einer gasturbinenanlage
US6595002B2 (en) * 2001-05-01 2003-07-22 Abb Schweiz Ag Vibration reduction in a combustion chamber
EP1342952A1 (de) * 2002-03-07 2003-09-10 Siemens Aktiengesellschaft Brenner, Verfahren zum Betrieb eines Brenners und Gasturbine
EP1342953A1 (de) 2002-03-07 2003-09-10 Siemens Aktiengesellschaft Gasturbine
EP1429002A2 (de) * 2002-12-07 2004-06-16 Alstom Technology Ltd Verfahren und Vorrichtung zur Beeinflussung thermoakustischer Schwingungen in Verbrennungssystemen
WO2004051063A1 (ja) * 2002-12-02 2004-06-17 Mitsubishi Heavy Industries, Ltd. ガスタービン燃焼器、及びこれを備えたガスタービン
EP1517087A1 (en) * 2003-09-16 2005-03-23 General Electric Company Method and apparatus to decrease combustor acoustics
WO2006014300A2 (en) * 2004-07-02 2006-02-09 Siemens Power Generation, Inc. Acoustically stiffened gas-turbine fuel nozzle
EP1662202A1 (de) * 2004-11-30 2006-05-31 Siemens Aktiengesellschaft Brenner für eine Gasturbinenanlage und Verfahren zum Betreiben eines derartigen Brenners
US7331182B2 (en) 2002-01-16 2008-02-19 Alstom Technology Ltd Combustion chamber for a gas turbine
EP2187125A1 (de) 2008-09-24 2010-05-19 Siemens Aktiengesellschaft Vorrichtung und Verfahren zur Dämpfung von Verbrennungsschwingungen
US7726019B2 (en) 2008-05-15 2010-06-01 Alstom Technology Ltd. Method for reducing emissions from a combustor
US7827777B2 (en) 2008-05-15 2010-11-09 Alstom Technology Ltd. Combustor with reduced carbon monoxide emissions
EP2383514A1 (de) 2010-04-28 2011-11-02 Siemens Aktiengesellschaft Brennersystem und Verfahren zur Dämpfung eines solchen Brennersystems
EP2383515A1 (de) 2010-04-28 2011-11-02 Siemens Aktiengesellschaft Brennersystem und Verfahren zur Dämpfung eines solchen Brennersystems
WO2014173660A1 (en) 2013-04-23 2014-10-30 Siemens Aktiengesellschaft Combustion system of a flow engine and method for determining a dimension of a resonator cavity
EP2851618A1 (en) 2013-04-24 2015-03-25 Siemens Aktiengesellschaft Combustion system of a flow engine comprising a resonator
DE102010016547B4 (de) 2009-07-08 2023-03-16 General Electric Co. Injektor mit integriertem Resonator

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
RU2508506C2 (ru) * 2009-09-01 2014-02-27 Дженерал Электрик Компани Способ и установка для ввода текучей среды в камеру сгорания газотурбинного двигателя

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE2350338B1 (de) * 1973-10-06 1975-04-03 Koppers Gmbh Heinrich Einrichtung zur Vermeidung von Brennkammerschwingungen
EP0119634A2 (en) * 1983-03-22 1984-09-26 Nippondenso Co., Ltd. Resonator for internal combustion engines
DE3439903A1 (de) * 1983-11-02 1985-05-09 Philip Joseph Aylesbury Buckinghamshire Dines Verbrennungssystem fuer ein gasturbinentriebwerk

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE2350338B1 (de) * 1973-10-06 1975-04-03 Koppers Gmbh Heinrich Einrichtung zur Vermeidung von Brennkammerschwingungen
EP0119634A2 (en) * 1983-03-22 1984-09-26 Nippondenso Co., Ltd. Resonator for internal combustion engines
DE3439903A1 (de) * 1983-11-02 1985-05-09 Philip Joseph Aylesbury Buckinghamshire Dines Verbrennungssystem fuer ein gasturbinentriebwerk

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
GWF GAS ERDGAS Bd. 112, Nr. 8, August 1971, MüNCHEN Seiten 367 - 375 LORENZ 'Verbrennungsger{usche' *

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DE4339094A1 (de) * 1993-11-16 1995-05-18 Abb Management Ag Verfahren zur Dämpfung von thermoakustischen Schwingungen sowie Vorrichtung zur Durchführung des Verfahrens
GB2288660A (en) * 1994-04-23 1995-10-25 Abb Management Ag Apparatus for damping thermoacoustic vibrations in combustion chamber
DE4414232A1 (de) * 1994-04-23 1995-10-26 Abb Management Ag Vorrichtung zur Dämpfung von thermoakustischen Schwingungen in einer Brennkammer
EP0730122A1 (fr) * 1995-03-02 1996-09-04 Chaffoteaux Et Maury Brûleur à gaz présentant une discrétion acoustique améliorée
FR2731265A1 (fr) * 1995-03-02 1996-09-06 Chaffoteaux Et Maury Bruleur a gaz presentant une discretion acoustique amelioree
WO1998012478A1 (de) 1996-09-16 1998-03-26 Siemens Aktiengesellschaft Verfahren und einrichtung zur verbrennung von brennstoff mit luft
WO1998034067A1 (de) * 1997-02-04 1998-08-06 Siemens Aktiengesellschaft Brenneranordnung und verfahren zur aktiven dämpfung einer verbrennungsschwingung
WO1998035186A1 (de) * 1997-02-06 1998-08-13 Siemens Aktiengesellschaft Verfahren zur aktiven dämpfung einer verbrennungsschwingung und verbrennungsvorrichtung
WO1999006767A1 (de) * 1997-07-31 1999-02-11 Siemens Aktiengesellschaft Brenner
EP0926325A3 (en) * 1997-12-23 2001-04-25 United Technologies Corporation Apparatus for use with a liquid fuelled combustor
EP0985810A1 (de) * 1998-09-10 2000-03-15 Abb Research Ltd. Verfahren und Vorrichtung zum Minimieren thermoakustischer Schwingungen in Gasturbinenbrennkammern
US6840046B2 (en) 1998-09-10 2005-01-11 Alstom Method and apparatus for minimizing thermoacoustic vibrations in gas-turbine combustion chambers
EP1004823A3 (de) * 1998-11-10 2000-11-29 Asea Brown Boveri AG Dämpfungsvorrichtung zur Reduzierung der Schwingungsamplitude akustischer Wellen für einen Brenner
US6370879B1 (en) 1998-11-10 2002-04-16 Alstom Damping device for reducing the vibration amplitude of acoustic waves for a burner
WO2000034714A1 (de) * 1998-12-08 2000-06-15 Siemens Aktiengesellschaft Verbrennungsvorrichtung und verfahren zur verbrennung eines brennstoffs
US6615587B1 (en) 1998-12-08 2003-09-09 Siemens Aktiengesellschaft Combustion device and method for burning a fuel
WO2000034715A1 (en) * 1998-12-09 2000-06-15 Abb Alstom Power Uk Ltd. Modification of combustion reaction dynamics
US6305927B1 (en) 1998-12-15 2001-10-23 Abb Alstom Power (Schweiz) Ag Burner with acoustically damped fuel supply system
EP1010939A1 (de) * 1998-12-15 2000-06-21 ABB Alstom Power (Schweiz) AG Brennkammer mit akustisch gedämpftem Brennstoffversorgungssystem
DE19948674B4 (de) * 1999-10-08 2012-04-12 Alstom Verbrennungseinrichtung, insbesondere für den Antrieb von Gasturbinen
US6490864B1 (en) 1999-10-08 2002-12-10 Alstom (Switzerland) Ltd Burner with damper for attenuating thermo acoustic instabilities
GB2356246B (en) * 1999-10-08 2003-07-09 Abb Combustion apparatus in particular for driving gas turbines
DE19948674A1 (de) * 1999-10-08 2001-04-12 Abb Schweiz Ag Verbrennungseinrichtung, insbesondere für den Antrieb von Gasturbinen
EP1223381A2 (de) * 2001-01-10 2002-07-17 Robert Bosch Gmbh Verfahren zum Betrieb einer Gastherme
EP1223381A3 (de) * 2001-01-10 2004-08-04 Robert Bosch Gmbh Verfahren zum Betrieb einer Gastherme
US6595002B2 (en) * 2001-05-01 2003-07-22 Abb Schweiz Ag Vibration reduction in a combustion chamber
US7104065B2 (en) 2001-09-07 2006-09-12 Alstom Technology Ltd. Damping arrangement for reducing combustion-chamber pulsation in a gas turbine system
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WO2004051063A1 (ja) * 2002-12-02 2004-06-17 Mitsubishi Heavy Industries, Ltd. ガスタービン燃焼器、及びこれを備えたガスタービン
US7832211B2 (en) 2002-12-02 2010-11-16 Mitsubishi Heavy Industries, Ltd. Gas turbine combustor and a gas turbine equipped therewith
EP1429002A2 (de) * 2002-12-07 2004-06-16 Alstom Technology Ltd Verfahren und Vorrichtung zur Beeinflussung thermoakustischer Schwingungen in Verbrennungssystemen
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US7464552B2 (en) 2004-07-02 2008-12-16 Siemens Energy, Inc. Acoustically stiffened gas-turbine fuel nozzle
WO2006014300A3 (en) * 2004-07-02 2006-03-23 Siemens Power Generation Inc Acoustically stiffened gas-turbine fuel nozzle
EP1662202A1 (de) * 2004-11-30 2006-05-31 Siemens Aktiengesellschaft Brenner für eine Gasturbinenanlage und Verfahren zum Betreiben eines derartigen Brenners
US7827777B2 (en) 2008-05-15 2010-11-09 Alstom Technology Ltd. Combustor with reduced carbon monoxide emissions
US7726019B2 (en) 2008-05-15 2010-06-01 Alstom Technology Ltd. Method for reducing emissions from a combustor
EP2187125A1 (de) 2008-09-24 2010-05-19 Siemens Aktiengesellschaft Vorrichtung und Verfahren zur Dämpfung von Verbrennungsschwingungen
DE102010016547B4 (de) 2009-07-08 2023-03-16 General Electric Co. Injektor mit integriertem Resonator
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EP0611434A1 (de) 1994-08-24
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