Concentric circle type pure hydrogen combustion micro-mixing combustion chamber head

Abstract

The invention relates to the technical field of gas turbine engines, and discloses a concentric circle type pure hydrogen combustion micro-mixing combustion chamber head which is characterized in that a combustion bowl is arranged on a secondary hydrogen fuel nozzle, secondary hydrogen fuel realizes stable combustion of hydrogen in a low-working-condition central area on the downstream of the combustion bowl, and a stable low-speed central backflow area is formed on the leeside of the combustion bowl; and the central backflow area ensures good combustion stability of the secondary stage. Main-stage hydrogen fuel sprayed out of the inner ring radial spraying holes and the outer ring radial spraying holes is micro-premixed with incoming flow air, the effect of improving the mixing quality and spatial distribution uniformity of the hydrogen fuel in the premixing process is achieved, and the problem of backfire during combustion of the main-stage hydrogen fuel can be avoided; and meanwhile, a low-speed and relatively-large-scale large annular backflow vortex structure is formed on the leeward side of the V-shaped ring, stable combustion is carried out in the large annular backflow vortex, and therefore the stability and uniformity of main-stage hydrogen combustion are improved, and NOx emission is reduced.

Description

Technical Field

[0001] The invention relates to the technical field of gas turbine engines and discloses a concentric circle pure hydrogen combustion micro-mixing combustion chamber head. Background Art

[0002] Hydrogen energy power is the most anticipated technical approach to aviation carbon neutrality. Its main technical advantages are: liquid hydrogen as fuel for gas turbine engines has an energy density (calorific value) that is 2.78 times that of traditional aviation kerosene; hydrogen does not produce carbon oxides and smoke during the combustion process, that is, the amount of carbon dioxide released by burning hydrogen is zero, and zero carbon emissions can be achieved; hydrogen fuel has high thermal stability and high heat sink, and is a more ideal cooling medium for aviation power, and is more conducive to engine thermal management.

[0003] In the combustion chamber of an aircraft engine, common hydrogen combustion organization modes include micro-mixed premixed combustion and micro-mixed non-premixed combustion. Micro-mixed premixed combustion refers to the pre-mixing of hydrogen and air in a microchannel, and the mixed gas is ejected through the same nozzle hole. The use of premixed combustion can effectively reduce the emission of nitrogen oxides from hydrogen combustion. Under the condition of generating the same heat, the generation of nitrogen oxides from hydrogen premixed combustion can be reduced to 1 / 20 of that of aviation kerosene. However, the activity of hydrogen in the premixed reaction and the higher flame speed make the flame front thinner and make it easier for the flame to move upstream, which will increase the risk of flashback. Micro-mixed non-premixed combustion is a new type of combustion mode, also known as diffusion combustion. Hydrogen and air pass through the jet channel at high speed, hydrogen is injected at the air outlet, and the two are mixed and burned at the outlet of the microchannel. Compared with premixed combustion, diffusion combustion can avoid the "flashback" problem of hydrogen combustion, thereby improving combustion efficiency and stability. However, diffusion combustion is accompanied by higher nitrogen oxide emissions.

[0004] Therefore, problems such as flashback and high NOx emissions in the prior art still hinder the widespread application of hydrogen fueled gas turbine engines. Summary of the invention

[0005] The purpose of the present invention is to provide a concentric pure hydrogen combustion micro-mixing combustion chamber head, which can effectively suppress the hydrogen "backfire" problem and realize the stable combustion of hydrogen in the large and small annular recirculation vortices formed in the leeward area of ​​the combustion bowl and the V-shaped ring, thereby reducing the formation of local hot spots during the hydrogen combustion process, thereby effectively reducing the emission of nitrogen oxides.

[0006] In order to achieve the above technical effects, the technical solution adopted by the present invention is:

[0007] A concentric pure hydrogen combustion micro-mixing combustion chamber head, comprising:

[0008] A secondary hydrogen fuel nozzle, the secondary hydrogen fuel nozzle is a cylindrical structure, the secondary hydrogen fuel nozzle is provided with an annular fuel channel, and the outer wall of the secondary hydrogen fuel nozzle is provided with a secondary fuel spray hole connected with the annular fuel channel;

[0009] A combustion bowl, wherein the opening edge of the combustion bowl is fixedly connected to the secondary hydrogen fuel nozzle;

[0010] An inner annular cavity hydrogen fuel nozzle housing, wherein the inner annular cavity hydrogen fuel nozzle housing is coaxially sleeved on the outer periphery of the secondary-stage hydrogen fuel nozzle, a first fuel passage communicating with the primary-stage fuel pipeline is arranged inside the inner annular cavity hydrogen fuel nozzle housing, and an inner annular radial injection hole communicating with the first fuel passage is arranged on the inner annular cavity hydrogen fuel nozzle housing;

[0011] An outer annular cavity hydrogen fuel nozzle housing, wherein the outer annular cavity hydrogen fuel nozzle housing is coaxially sleeved on the outer periphery of the inner annular cavity hydrogen fuel nozzle housing, wherein a second fuel passage communicating with a primary fuel pipeline is arranged in the outer annular cavity hydrogen fuel nozzle housing, and an outer annular radial injection hole communicating with the second fuel passage is arranged on the outer annular cavity hydrogen fuel nozzle housing;

[0012] A V-shaped ring, wherein the inner edge of the opening of the V-shaped ring is fixedly connected to the inner ring cavity hydrogen fuel nozzle shell, and the outer edge of the opening of the V-shaped ring is fixedly connected to the outer ring cavity hydrogen fuel nozzle shell;

[0013] An outer sleeve is coaxially sleeved on the outer periphery of the outer ring cavity hydrogen fuel nozzle shell, and a first convergent channel is formed between the outer sleeve and the outer ring cavity hydrogen fuel nozzle shell along the air flow direction.

[0014] Furthermore, a radial swirler is provided between the inner annular hydrogen fuel nozzle housing and the secondary hydrogen fuel nozzle, a second convergent channel is formed between the radial swirler and the secondary hydrogen fuel nozzle along the air flow direction, and the outlet end of the secondary fuel spray hole is located in the second convergent channel.

[0015] Furthermore, a diverter ring is provided between the radial swirler and the inner annular cavity hydrogen fuel nozzle housing.

[0016] Furthermore, the splitter ring is fixed to the outer wall of the radial cyclone through a plurality of support blocks, and the plurality of support blocks are evenly distributed along the circumferential direction of the radial cyclone.

[0017] Furthermore, a first grid is provided between the outer wall of the diverter ring and the inner ring cavity hydrogen fuel nozzle housing.

[0018] Furthermore, the front edge of the diverter ring facing the wind is a streamlined structure.

[0019] Furthermore, air film holes are provided on the combustion bowl and the V-shaped ring, and impact plates are respectively arranged at the upstream positions of the airflow close to the combustion bowl and the V-shaped ring, and impact holes are provided on the impact plates.

[0020] Furthermore, a second grid is provided in the first convergent channel.

[0021] Compared with the prior art, the present invention has the following beneficial effects:

[0022] 1. The present invention performs micro-premixing on the hydrogen fuel ejected from the secondary fuel nozzle hole by entraining the air flowing through the outer wall of the secondary hydrogen fuel nozzle, which can not only make the mixing uniform and efficient, but also prevent the secondary hydrogen fuel combustion "backfire" problem; by arranging a combustion bowl on the secondary hydrogen fuel nozzle, the secondary hydrogen fuel realizes stable combustion of hydrogen in the low-operating condition central area downstream of the combustion bowl, and forms a stable low-speed central reflow area on the leeward side of the combustion bowl, and the central reflow area ensures good combustion stability performance of the secondary stage.

[0023] 2. The present invention achieves micro-premixing of the main-stage hydrogen fuel ejected from the inner ring radial injection holes and the outer ring radial injection holes with the incoming air respectively, thereby improving the mixing quality and spatial distribution uniformity of the hydrogen fuel during the premixing process, and further avoiding the problem of "backfire" of the main-stage hydrogen fuel combustion; at the same time, when the airflow entrained with the main-stage hydrogen fuel flows through the V-shaped ring, a low-speed and relatively large-scale large annular recirculation vortex structure is formed on the leeward side of the V-shaped ring, and stable combustion is carried out in the large annular recirculation vortex, thereby improving the stability and uniformity of the main-stage hydrogen combustion and reducing NOx emissions. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 This is a schematic diagram of the concentric pure hydrogen combustion micro-mixing combustion chamber head structure in the embodiment;

[0025] Figure 2 Schematic diagram of the formation of the central recirculation area and the small annular recirculation vortex in the embodiment;

[0026] Figure 3 Schematic diagram of the positional relationship between the inner annular cavity hydrogen fuel nozzle housing and the outer annular cavity hydrogen fuel nozzle housing in the embodiment;

[0027] Figure 4 Schematic diagram of the formation of a large annular recirculation vortex in the embodiment;

[0028] Among them, 1. secondary hydrogen fuel nozzle; 101. annular fuel channel; 102. secondary fuel spray hole; 2. combustion bowl; 3. inner annular hydrogen fuel nozzle shell; 301. first fuel channel; 302. inner annular radial spray hole; 4. outer annular hydrogen fuel nozzle shell; 401. second fuel channel; 402. outer annular radial spray hole; 5. V-ring; 6. outer sleeve; 7. first convergent channel; 8. radial swirler; 9. second convergent channel; 10. diverter ring; 11. support block; 12. first grid; 13. air film hole; 14. impact plate; 15. impact hole; 16. second grid; 17. central recirculation area; 18. large annular recirculation vortex; 19. small annular recirculation vortex. DETAILED DESCRIPTION

[0029] The present invention is further described in detail below in conjunction with the embodiments and drawings. However, it should not be understood that the scope of the above subject matter of the present invention is limited to the following embodiments, and all technologies realized based on the content of the present invention belong to the scope of the present invention.

[0030] Example

[0031] See also Figure 1-Figure 4 , a concentric pure hydrogen combustion micro-mixing combustion chamber head, comprising:

[0032] A secondary hydrogen fuel nozzle 1, the secondary hydrogen fuel nozzle 1 is a cylindrical structure, the secondary hydrogen fuel nozzle 1 is provided with an annular fuel channel 101, and the outer wall of the secondary hydrogen fuel nozzle 1 is provided with a secondary fuel spray hole 102 connected with the annular fuel channel 101;

[0033] A combustion bowl 2, wherein the opening edge of the combustion bowl 2 is fixedly connected to the secondary hydrogen fuel nozzle 1;

[0034] An inner annular hydrogen fuel nozzle housing 3, wherein the inner annular hydrogen fuel nozzle housing 3 is coaxially sleeved on the outer periphery of the secondary hydrogen fuel nozzle 1, wherein a first fuel passage 301 communicating with the primary fuel pipeline is provided inside the inner annular hydrogen fuel nozzle housing 3, and an inner annular radial injection hole 302 communicating with the first fuel passage 301 is provided on the inner annular hydrogen fuel nozzle housing 3;

[0035] An outer annular cavity hydrogen fuel nozzle housing 4, wherein the outer annular cavity hydrogen fuel nozzle housing 4 is coaxially sleeved on the outer periphery of the inner annular cavity hydrogen fuel nozzle housing 3, wherein a second fuel passage 401 communicating with a primary fuel pipeline is provided in the outer annular cavity hydrogen fuel nozzle housing 4, and an outer annular radial injection hole 402 communicating with the second fuel passage 401 is provided on the outer annular cavity hydrogen fuel nozzle housing 4;

[0036] A V-shaped ring 5, wherein the inner edge of the opening of the V-shaped ring 5 is fixedly connected to the inner ring cavity hydrogen fuel nozzle shell 3, and the outer edge of the opening of the V-shaped ring 5 is fixedly connected to the outer ring cavity hydrogen fuel nozzle shell 4;

[0037] The outer sleeve 6 is coaxially sleeved on the outer periphery of the outer ring cavity hydrogen fuel nozzle housing 4, and a first convergent channel 7 is formed between the outer sleeve 6 and the outer ring cavity hydrogen fuel nozzle housing 4 along the air flow direction.

[0038] In this embodiment, the secondary hydrogen fuel is ejected from the secondary fuel nozzle hole 102 located on the outer wall of the secondary hydrogen fuel nozzle 1, and the air flowing through the outer wall of the secondary hydrogen fuel nozzle 1 carries out micro-premixing of the hydrogen fuel ejected from the secondary fuel nozzle hole 102, which not only makes the mixing uniform and efficient, but also prevents the secondary hydrogen fuel combustion "backfire" problem; by arranging the combustion bowl 2 on the secondary hydrogen fuel nozzle 1, the secondary hydrogen fuel realizes stable combustion of hydrogen in the low-operating condition central area downstream of the combustion bowl 2, and forms a stable low-speed central recirculation area 17 on the leeward side of the combustion bowl 2, and the central recirculation area 17 ensures good secondary combustion stability performance. In addition, a first micro-premixing channel for mixing the main-stage hydrogen fuel ejected from the inner-ring radial injection hole 302 is formed between the inner-ring hydrogen fuel nozzle shell 3 and the secondary-stage hydrogen fuel nozzle 1, and a second micro-premixing channel for mixing the main-stage hydrogen fuel ejected from the outer-ring radial injection hole 402 is formed between the outer sleeve 6 and the outer-ring hydrogen fuel nozzle shell 4, together forming a main-stage double-ring hydrogen fuel channel; the main-stage hydrogen fuel ejected from the inner-ring radial injection hole 302 and the outer-ring radial injection hole 402 are respectively micro-premixed with the incoming air, entraining the main-stage hydrogen fuel. When the hydrogen fuel airflow flows through the V-shaped ring 5, a low-speed and relatively large-scale large annular recirculation vortex 18 structure is formed on the leeward side of the V-shaped ring 5, and stably burns in the large annular recirculation vortex 18, thereby reducing the formation of local hot spots during the hydrogen combustion process, thereby improving the stability and uniformity of the main-stage hydrogen combustion and reducing NOx emissions; the first micro-premixing channel and the second micro-premixing channel play a role in improving the mixing quality and spatial distribution uniformity of the hydrogen fuel during the premixing process, and can further avoid the problem of "backfire" in the main-stage hydrogen fuel combustion.

[0039] In this embodiment, a radial swirler 8 is provided between the inner annular cavity hydrogen fuel nozzle housing 3 and the secondary hydrogen fuel nozzle 1, and a second convergent channel 9 is formed between the radial swirler 8 and the secondary hydrogen fuel nozzle 1 along the air flow direction, and the outlet end of the secondary fuel nozzle 102 is located in the second convergent channel 9. The radial swirler 8 can not only improve the micro-premixing effect of the secondary hydrogen fuel, but also accelerate the airflow entrained with the secondary hydrogen fuel by forming the second convergent channel 9 between the radial swirler 8 and the secondary hydrogen fuel nozzle 1, thereby facilitating the stable formation of the central reflow zone 17 on the leeward side of the combustion bowl 2.

[0040] In this embodiment, a diverter ring 10 is provided between the radial swirler 8 and the inner ring cavity hydrogen fuel nozzle shell 3. Under this structure, the airflow flowing through the radial swirler 8 and the inner ring cavity hydrogen fuel nozzle shell 3 is divided into two streams by the diverter ring 10, and the two airflows flow out from the inner channel and the outer channel of the diverter ring 10 respectively, and form a low-speed small annular recirculation vortex 19 structure on the leeward side of the diverter ring 10, further ensuring the stable combustion of the main stage hydrogen fuel ejected from the inner ring radial injection hole 302. In order to reduce the disturbance effect of the diverter ring 10 on the airflow, the front edge of the diverter ring 10 facing the wind in this embodiment is a streamlined structure.

[0041] In this embodiment, the splitter ring 10 is fixed to the outer wall of the radial cyclone 8 by a plurality of support blocks 11, and the plurality of support blocks 11 are evenly distributed along the circumferential direction of the radial cyclone 8 to achieve the fixation of the splitter ring 10.

[0042] In this embodiment, a first grid 12 is arranged between the outer wall of the diverter ring 10 and the inner ring cavity hydrogen fuel nozzle shell 3, and a second grid 16 is also arranged in the first convergent channel 7; the first convergent channel 7 and the convergent channel outside the diverter ring 10 are further subdivided into multi-point array hydrogen jet-cross flow microchannels by the corresponding first grid 12 or second grid 16, so as to realize uniform mixing of hydrogen fuel and further enhance the inhibitory effect on the hydrogen "backfire" problem.

[0043] In this embodiment, the combustion bowl 2 and the V-shaped ring 5 are both provided with air film holes 13, and impact plates 14 are respectively provided at the upstream positions of the airflow near the combustion bowl 2 and the V-shaped ring 5, and the impact plates 14 are provided with impact holes 15. In this embodiment, the impact plate 14 is provided with multiple circles of impact holes 15 evenly distributed along the circumferential direction, and the combustion bowl 2 is provided with multiple circles of divergent air film holes 13 evenly distributed along the circumferential direction. The impact holes 15 and the divergent air film holes 13 are staggered in the radial and circumferential directions; the cooling airflow from the impact holes 15 on the impact plate 14 passes through multiple rows of divergent air film holes 13 on the combustion bowl 2 to form a wall-attached airflow, which can prevent the combustion bowl 2 from being ablated. Similarly, the impact plate 14 in front of the V-shaped ring 5 and the impact holes 15 and air film holes 13 on its corresponding structure can also form a wall-attached airflow to avoid the problem of V-shaped ring 5 ablation.

[0044] like Figure 1As shown, the impact plate 14 corresponding to the combustion bowl 2 in this embodiment is an arched structure, and the arched structure protrudes in the direction away from the combustion bowl 2. The arched impact plate 14 and the combustion bowl 2 are arranged in the center of the head, and the arched impact plate 14 is located on the left side of the combustion bowl 2, and the right end is mounted on the periphery of the combustion bowl 2 and forms a certain gap between the combustion bowl 2; the right end of the secondary hydrogen fuel nozzle 1 overlaps the periphery of the arched impact plate 14 and is welded flush with the outer edge of the combustion bowl 2. The radial swirler 8 is mounted on the outside of the secondary hydrogen fuel nozzle 1, and the right end is flush with the right end of the combustion bowl 2. The support block 11 is welded to the periphery of the right end of the radial swirler 8, and the diverter ring 10 is radially arranged on the outside of the support block 11, and the right end face is flush with the right end of the radial swirler 8. The outer sleeve 6 is mounted on the outside of the second grid 16, and the outer surface of the outer sleeve 6 is provided with a mounting positioning lug.

[0045] The above are only preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A concentric pure hydrogen combustion micro-mixing combustion chamber head, characterized in that: include: A secondary hydrogen fuel nozzle, the secondary hydrogen fuel nozzle is a cylindrical structure, the secondary hydrogen fuel nozzle is provided with an annular fuel channel, and the outer wall of the secondary hydrogen fuel nozzle is provided with a secondary fuel spray hole connected with the annular fuel channel; A combustion bowl, wherein the opening edge of the combustion bowl is fixedly connected to the secondary hydrogen fuel nozzle; An inner annular cavity hydrogen fuel nozzle housing, wherein the inner annular cavity hydrogen fuel nozzle housing is coaxially sleeved on the outer periphery of the secondary-stage hydrogen fuel nozzle, a first fuel passage communicating with the primary-stage fuel pipeline is arranged inside the inner annular cavity hydrogen fuel nozzle housing, and an inner annular radial injection hole communicating with the first fuel passage is arranged on the inner annular cavity hydrogen fuel nozzle housing; An outer annular cavity hydrogen fuel nozzle housing, wherein the outer annular cavity hydrogen fuel nozzle housing is coaxially sleeved on the outer periphery of the inner annular cavity hydrogen fuel nozzle housing, wherein a second fuel passage communicating with a primary fuel pipeline is arranged in the outer annular cavity hydrogen fuel nozzle housing, and an outer annular radial injection hole communicating with the second fuel passage is arranged on the outer annular cavity hydrogen fuel nozzle housing; A V-shaped ring, wherein the inner edge of the opening of the V-shaped ring is fixedly connected to the inner ring cavity hydrogen fuel nozzle shell, and the outer edge of the opening of the V-shaped ring is fixedly connected to the outer ring cavity hydrogen fuel nozzle shell; An outer sleeve is coaxially sleeved on the outer periphery of the outer ring cavity hydrogen fuel nozzle shell, and a first convergent channel is formed between the outer sleeve and the outer ring cavity hydrogen fuel nozzle shell along the air flow direction.

2. The concentric pure hydrogen combustion micro-mixing combustion chamber head according to claim 1 is characterized in that: A radial swirler is provided between the inner annular hydrogen fuel nozzle housing and the secondary hydrogen fuel nozzle, a second convergent channel is formed between the radial swirler and the secondary hydrogen fuel nozzle along the air flow direction, and the outlet end of the secondary fuel spray hole is located in the second convergent channel.

3. The concentric pure hydrogen combustion micro-mixing combustion chamber head according to claim 2 is characterized in that: A flow divider ring is arranged between the radial swirler and the inner annular cavity hydrogen fuel nozzle housing.

4. The concentric pure hydrogen combustion micro-mixing combustion chamber head according to claim 3 is characterized in that: The splitter ring is fixed to the outer wall of the radial cyclone through a plurality of support blocks, and the plurality of support blocks are evenly distributed along the circumferential direction of the radial cyclone.

5. The concentric pure hydrogen combustion micro-mixing combustion chamber head according to claim 3 is characterized in that: A first grid is arranged between the outer wall of the splitter ring and the inner ring cavity hydrogen fuel nozzle housing.

6. The concentric pure hydrogen combustion micro-mixing combustion chamber head according to any one of claims 3 to 5, characterized in that: The front edge of the diverter ring facing the wind is a streamlined structure.

7. The concentric pure hydrogen combustion micro-mixing combustion chamber head according to claim 1, characterized in that: Air film holes are provided on the combustion bowl and the V-shaped ring, and impact plates are respectively arranged at the upstream positions of the airflow close to the combustion bowl and the V-shaped ring, and impact holes are provided on the impact plates.

8. The concentric pure hydrogen combustion micro-mixing combustion chamber head according to claim 1, characterized in that: A second grid is also disposed in the first convergent channel.

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