A kind of low swirl nozzle of gas-turbine combustion chamber
Technical field
The present invention relates to a kind of low swirl nozzle of gas-turbine combustion chamber, belong to gas turbine structure design field.
Background technology
A kind of low swirl nozzle applied to gas-turbine combustion chamber is disclosed in the prior art.As shown in figure 1, in low rotation
In flow nozzle 10, fuel is entered by fuel inlet tube 101, and air is entered by air intlet 501, and fuel and air are in Wen
Mixed in pipe 601.The downstream of Venturi tube 601 is double-decker, and wherein nozzle inner flow passage 401 sets a restriction orifice 301, current limliting
Multiple metering holes 302 are evenly arranged on orifice plate 301;Nozzle outer flow passage 402 sets cyclone 201, and cyclone 201 is by multiple eddy flows
Blade is constituted.Upstream homogeneous mixture produces low eddy flow gaseous mixture, into combustion respectively by cyclone 201 and restriction orifice 301
Expansion regions 403 are burnt to burn.To make fuel and air well mixed, the axial length L of Venturi tube 6011Generally 150mm~220mm
Between, cause nozzle long, when being used cooperatively with other types nozzle, installation is brought inconvenience;In addition, into nozzle
The fuel-air mixture example of inner flow passage 401 and nozzle outer flow passage 402 is consistent, the combustion entered completely by fuel inlet tube 101
Doses and the air capacity entered by air intlet 501 are determined, it is impossible to which the fuel-air mixture example to outer flow passage in nozzle is entered
Row reasonable distribution.
Fig. 2 is another embodiment of the prior art, and fuel directly enters from cyclone 201 and the downstream of restriction orifice 301
Enter to burn expansion regions 403, it is impossible to forms premix gas in time with air, and partial combustion temperature is too high in expansion regions 403 of burning, generally
Higher than 2000K, cause the content of nitrogen oxides in combustion chamber to uprise, pollute environment.
The content of the invention
In order to solve problems of the prior art, the present invention proposes a kind of low swirl nozzle of gas-turbine combustion chamber,
Nozzle length can be reduced, and reasonable distribution can be carried out to the fuel-air mixture example of outer flow passage in nozzle, further to drop
Low burn burns indoor pollutant.
The technical solution adopted in the present invention is as follows:
A kind of low swirl nozzle of gas-turbine combustion chamber, including fuel inlet tube, air intlet, nozzle inner flow passage, nozzle
Outer flow passage, restriction orifice, cyclone and burning expansion segment;Described restriction orifice is arranged in the nozzle inner flow passage, described
Cyclone is arranged in nozzle outer flow passage, and the burning expansion segment is arranged on the downstream of nozzle inner flow passage and nozzle outer flow passage,
It is characterized in that:The low swirl nozzle in the combustion chamber includes a fuel nozzle device, and the fuel nozzle device is arranged at metering hole
The upstream of plate and cyclone, the fuel nozzle device includes at least four fuel nozzles, and fuel nozzle is along fuel inlet tube
Even circumferential is distributed, and one end of every fuel nozzle is connected with fuel inlet tube, the other end and low swirl nozzle outer flow passage
Outer wall is connected;The every fuel nozzle is divided into fuel nozzle inner tube and fuel nozzle outer tube, and fuel nozzle inner tube is in described
In nozzle inner flow passage, fuel nozzle outer tube is in nozzle outer flow passage;Propellant spray hole is set in fuel nozzle inner tube, in combustion
Expect to set propellant spray hole on jet pipe outer tube.
In above-mentioned technical proposal, axial distance L of the fuel nozzle device away from the cyclone215mm~30mm it
Between,
The technical characteristic of the present invention is also resided in, the inner fuel spray orifice and outside propellant spray hole a diameter of 1~
2mm a diameter of 1~2mm;In the inner fuel spray orifice and the center line and fuel inlet tube in outside propellant spray hole
Heart line is in 90 °;Propellant spray hole in fuel nozzle inner tube is evenly arranged along nozzle inner flow passage radial position or straggly is arranged in
The both sides of fuel nozzle inner tube wall;Propellant spray hole on fuel nozzle outer tube is evenly arranged along nozzle outer flow passage radial position
Or arranged crosswise is in the both sides of fuel nozzle wall.
The present invention another technical characteristic be:The quantity of the fuel nozzle keeps one with the swirler blades quantity
Cause, preferably 6~20, it is shaped as pipe, conical pipe or oval pipe.
The present invention has the advantages that following prominent and beneficial effect compared with prior art:
Fuel nozzle wall of outer flow passage in nozzle is separated as two described in low swirl nozzle device of the present invention
Section, fuel enters part incoming fuel jet pipe inner tube after the fuel nozzle, is entered by the propellant spray hole of fuel nozzle inner tube
Enter nozzle inner flow passage, remaining incoming fuel jet pipe outer tube enters nozzle outer flow passage by the propellant spray hole of fuel nozzle outer tube.
Axial distance L of the fuel nozzle away from the cyclone2Between 15mm~30mm, although in the cyclone and described
Restriction orifice upstream fuel and air mixing distance shorten, but in the cyclone and the restriction orifice downstream fuel and
Air can continue mixing, and the length of low swirl nozzle is greatly reduced on the premise of mixing mixed performance is ensured, is improved
The installation harmony of low swirl nozzle;Fuel-air into the nozzle inner flow passage and the combustion into the nozzle outer flow passage
Material AIR Proportional can be lowered into the spray by controlling propellant spray hole aperture on fuel nozzle and quantity to control
The fuel-air ratio of mouth inner flow passage, can be lowered into the fuel quantity in the Central backflow area of fired downstream expansion regions, reduce back
The high-temperature region in area is flowed, and then reduces the generation of nitrogen oxides, reduction pollution.
Brief description of the drawings
Fig. 1 is one low swirl nozzle sketch in the prior art.
Fig. 2 is another low swirl nozzle sketch in the prior art.
The structure diagram for the low swirl nozzle embodiment of gas-turbine combustion chamber that Fig. 3 provides for the present invention.
Fig. 4 is Fig. 3 A-A profiles.
Symbol description in figure:The low swirl nozzles of 10-;101- fuel inlet tubes;102a- fuel nozzle inner tubes;102b- fuel
Jet pipe outer tube;103a- inner fuel spray orifices;Propellant spray hole on the outside of 103b-;201- cyclones;301- restriction orifices;302-
Metering hole;401- nozzle inner flow passages;402- nozzle outer flow passages;403- burnings expansion regions;501- air intlets;601- Venturi tubes.
Embodiment
Structure, principle and the course of work to the present invention elaborate below in conjunction with the accompanying drawings:
The structure diagram for the low swirl nozzle embodiment of gas-turbine combustion chamber that Fig. 3 and Fig. 4 provides for the present invention, the burning
The low swirl nozzle in room includes fuel inlet tube 101, air intlet 501, nozzle inner flow passage 401, nozzle outer flow passage 402, metering hole
Plate 301, cyclone 201, burning expansion segment 403 and fuel nozzle device;Described restriction orifice 301 is arranged in the nozzle
Multiple metering holes 302 are evenly arranged in runner 401, on restriction orifice;The cyclone 201 is arranged in nozzle outer flow passage 402,
Cyclone is made up of multiple swirl vanes;The burning expansion segment 403 is arranged on nozzle inner flow passage 401 and nozzle outer flow passage
402 downstream.The fuel nozzle device is arranged at the upstream of restriction orifice 301 and cyclone 201, fuel nozzle device bag
At least four fuel nozzles are included, and fuel nozzle is distributed along the even circumferential of fuel inlet tube 101, one end of every fuel nozzle
It is connected with fuel inlet tube 101, the other end is connected with the outflow pipeline outer wall of low swirl nozzle;The every fuel nozzle is divided into
Fuel nozzle inner tube 102a and fuel nozzle outer tube 102b, the fuel nozzle inner tube 102a are connected with fuel nozzle outer tube 102b
It is logical;Fuel nozzle inner tube 102a is in the nozzle inner flow passage 401, and fuel nozzle outer tube 102b is in nozzle outer flow passage 402
It is interior;Fuel nozzle can use one, can also be divided to two sections of processing, be respectively welded in nozzle in outer flow passage;In fuel nozzle
Inner fuel spray orifice 103a is set on inner tube 102a, the propellant spray hole 103b on the outside of setting on fuel nozzle outer tube 102b
(as shown in Figure 4).
Axial distance L of the fuel nozzle device away from cyclone 2012It is preferred that between 15mm~30mm, fuel and air without
It need to be well mixed entering in nozzle before outer flow passage, can continue to mix in cyclone 201 and the downstream of restriction orifice 301,
The length of low swirl nozzle is greatly reduced on the premise of guarantee mixed performance, the installation harmony of low swirl nozzle is improved.
Inner fuel spray orifice 103a and outside propellant spray hole 103b diameter are generally 1~2mm, and the center line in propellant spray hole
It it is in 90 ° with low swirl nozzle center line, it is ensured that the depth of penetration and blending performance of fuel.The quantity of fuel nozzle typically with rotation
The stream blade quantity of device 201 is consistent, preferably 6~20, and fuel nozzle is shaped as pipe, conical pipe or oval pipe.
Inner fuel spray orifice 103a on fuel nozzle inner tube 102a is evenly arranged along the radial position of nozzle inner flow passage 401
Or the both sides straggly for being arranged in fuel nozzle inner tube wall;Outside propellant spray hole 103b edges spray on fuel nozzle outer tube 102b
The radial position of mouth outer flow passage 402 is evenly arranged or arranged crosswise is in the both sides of fuel nozzle outer tube wall;In fuel nozzle inner tube
Both sides arrange propellant spray hole, it is ensured that fuel nozzle inner tube both sides fuel ratio is uniform compared with convergence, it is ensured that passed through in fuel
Wear depth it is not high when still there is good mixed performance, because internal layer fuel quantity is relatively low, to ensure that it is reasonable that it still has
The ground depth of penetration, the hole count in propellant spray hole needs the fewer of setting.
The course of work of the present invention is as follows:
Fuel enters from fuel inlet tube 101, is entered respectively by the fuel nozzle device being connected with fuel inlet tube 101
Enter fuel nozzle inner tube 102a and fuel nozzle outer tube 102b, a part is sprayed by the inner fuel on fuel nozzle inner tube 102a
Orifice 103a enters nozzle inner flow passage 401;Another part flows into fuel nozzle outer tube 102b, and passes through inner fuel spray respectively
Hole 103a and outside propellant spray hole 103b sprays into nozzle inner flow passage 401 and nozzle outer flow passage 402;Air is from front air intlet
501 respectively enter nozzle inner flow passage 401 and nozzle outer flow passage 402, by mixing shape with the fuel sprayed during fuel nozzle device
Into fuel-air mixture, the fuel-air mixture in nozzle inner flow passage 401 flows through restriction orifice 301, nozzle outer flow passage 402
Interior fuel-air mixture flows through cyclone 201, and two strands of gaseous mixtures converge to form low vortex gas-flow in nozzle downstream, flows into combustion
Burn expansion regions 403 to be burnt, by controlling the fuel on fuel nozzle inner tube 102a and fuel nozzle outer tube 102b to spray
The aperture of orifice and quantity can be controlled to the fuel quantity of outer flow passage in nozzle, and then control to enter outer flow passage in nozzle
Fuel-air ratio, the fuel-air ratio that control enters nozzle inner flow passage 401 is less than the fuel sky for entering nozzle outer flow passage 402
Gas ratio.Even if the recirculating zone of low swirl nozzle is smaller, the center of combustion zone still suffers from recirculating zone, and control enters in recirculating zone
Fuel quantity, can reduce the high-temperature region in recirculating zone, and then reduce NOX generation, reduce pollution.