A premixed main combustion and diffused secondary combustion circumferential recirculation hydrogen combustion head and its usage method

Abstract

This invention relates to the field of hydrogen combustion technology and discloses a premixed main combustion and diffused secondary combustion circumferential recirculation hydrogen combustion head and its usage method. The central blunt body includes two first sidewalls and a second sidewall, with the two first sidewalls symmetrically arranged around the center of the second sidewall. A hydrogen inlet pipe is provided at the top of the central blunt body. A main mold hydrogen outlet pipe is provided on each of the first sidewalls, and a secondary mold hydrogen outlet pipe is provided on the second sidewall. Both the main mold hydrogen outlet pipe and the secondary mold hydrogen outlet pipe are connected to the hydrogen inlet pipe. Two guide plates are respectively arranged parallel to the outer sidewalls of the two first sidewalls. The inner sidewalls of the two guide plates and the outer sidewalls of the two first sidewalls form two mixing channels. The gas outlet direction of the mixing channel is parallel to the gas outlet direction of the main mold hydrogen outlet pipe. This application achieves efficient mixing and stable combustion of hydrogen and air through structural design, improves combustion efficiency, reduces pollutant emissions, enhances the stability of the combustion process, and avoids backfire.

Description

Technical Field

[0001] This invention relates to the field of hydrogen combustion technology, and discloses a circumferential recirculation hydrogen combustion head with main combustion premixing and secondary combustion diffusion, as well as its usage method. Background Technology

[0002] The main function of the combustion chamber in aircraft engines and industrial gas turbines is to carry out combustion reactions, converting the chemical energy of fuel into thermal energy, heating the incoming fluid, and improving the working capacity of the working fluid.

[0003] In traditional radial swirl combustor head configurations, fuel is often injected perpendicularly into the incoming airflow (through cross-flow penetration) to achieve rapid mixing over a short mixing distance. However, the depth of fuel penetration and the trajectory of the fuel jet are affected by the momentum ratio of the fuel jet to the incoming airflow (J=ρV). j 2 / ρV ∞ 2 The impact of ).

[0004] When the momentum ratio is very low, the fuel penetration depth is shallow, meaning that fuel tends to accumulate on the wall of the mixing section on the same side of the fuel nozzle. Due to viscosity, the flow velocity near the wall is relatively low, increasing the risk of flame entrapment, especially considering the relatively fast flame propagation speed of hydrogen. This implies that in conventional radial cyclones using hydrogen as fuel in the mixing section (cross-flow penetration configuration), the risk of backfire may increase when the momentum ratio is low.

[0005] When the momentum ratio is too high, the hydrogen penetration intensity is too high, and the hydrogen jet reaches and accumulates on the upper wall of the mixing section, which also increases the risk of flame presence on the upper wall.

[0006] Even when the momentum ratio is appropriate, the trajectory and mixing quality of the hydrogen jet will still be affected by the change in momentum ratio caused by the change in operating conditions (from small operating conditions to large operating conditions). This means that the fuel distribution, temperature field distribution and NO2 emissions in the downstream combustion zone will also be affected.

[0007] Chinese Patent (Publication No.: CN117232009A) discloses a structure of an injection unit at the head of a gas turbine combustor. Referring to Figures 8 and 9 of the published patent, fuel gas enters the gas collecting ring of the gas supply pipe from the intake pipe, and is injected into the air flow channel between the inner wall of the gas collecting ring and the inner hub of the inner mixing cyclone through the inner injection hole. It then enters the premixing section for mixing along with the swirling air flowing through the blades of the inner mixing cyclone. At the same time, it is injected into the outer wall of the gas collecting ring and the outer cyclone through the outer injection hole.

[0008] According to the aforementioned patent, the inner injection hole of the fuel (hydrogen) is perpendicular to the inner wall of the gas collecting ring. When mixing with air, if the hydrogen injection hole is at a vertical angle, the hydrogen is easily injected onto the solid wall surface, forming a local accumulation of hydrogen. Near the wall surface, the flow velocity is relatively low due to viscosity. At this time, the flame velocity caused by the accumulated hydrogen is greater than the flow velocity near the wall surface, causing the flame to remain dormant and backfire to occur.

[0009] Therefore, there is an urgent need to develop a hydrogen combustion head and method of application that features primary combustion premixing and secondary combustion diffusion circumferential recirculation, in order to improve the efficiency and stability of hydrogen combustion and avoid backfire. Summary of the Invention

[0010] The purpose of this invention is to provide a premixed main combustion and diffused secondary combustion circumferential recirculation hydrogen combustion head and its usage method. Through structural design, it achieves efficient mixing and stable combustion of hydrogen and air, improves combustion efficiency, reduces pollutant emissions, enhances the stability of the combustion process, and avoids backfire.

[0011] To achieve the above-mentioned technical effects, the technical solution adopted by the present invention is: a circumferential recirculation hydrogen combustion head with main combustion premixing and secondary combustion diffusion, comprising:

[0012] A central blunt body includes two first sidewalls and a second sidewall. The two first sidewalls are symmetrically arranged with respect to the center of the second sidewall, and the two first sidewalls are inclined towards the second sidewall. A hydrogen inlet pipe is provided at the top of the central blunt body. A main mold hydrogen outlet pipe is provided on each of the two first sidewalls, and a secondary mold hydrogen outlet pipe is provided on the second sidewall. Both the main mold hydrogen outlet pipe and the secondary mold hydrogen outlet pipe are connected to the hydrogen inlet pipe.

[0013] Two flow guide plates are respectively arranged parallel to the outer walls of the two first side walls. The inner walls of the two flow guide plates and the outer walls of the two first side walls form two mixing channels for mixing hydrogen and air from the hydrogen outlet pipe of the main mold.

[0014] The outlet direction of the mixing channel is parallel to the outlet direction of the hydrogen outlet pipe of the main mold.

[0015] As a preferred implementation scheme, it also includes:

[0016] Two diverter plates are respectively arranged parallel to the outer walls of two guide plates. The outer walls of the two guide plates and the inner walls of the two diverter plates form two air conditioning channels for diverting the air entering the mixing channel. By adjusting the distance between the diverter plates and the guide plates, the area ratio of the air conditioning channel and the mixing channel is controlled, thereby adjusting the airflow rate entering the mixing channel.

[0017] As a preferred embodiment, the two air conditioning channels are equipped with rotatable guide vanes, and the airflow entering the mixing channel can be adjusted by adjusting the angle of the guide vanes.

[0018] In a preferred embodiment, the central blunt body has a triangular cross-sectional shape, and the angle between the two first sidewalls and the second sidewall is 50°–75°.

[0019] As a preferred embodiment, the hydrogen outlet pipe of the sub-mold is located at the center of the second side wall, and both the hydrogen outlet pipe of the main mold and the hydrogen outlet pipe of the sub-mold are provided with several pipes along the height direction of the central blunt body.

[0020] To achieve the above-mentioned technical effects, the present invention also provides a method for using a circumferential recirculation hydrogen combustion head with primary combustion premixing and secondary combustion diffusion, comprising the following steps:

[0021] Hydrogen is introduced through the hydrogen inlet pipe at the top of the central blunt body, and then flows out through the hydrogen outlet pipes of the main mold and the secondary mold respectively.

[0022] Using the drainage plates located on the outer walls of the two first side walls of the central blunt body, the hydrogen gas flowing out of the hydrogen outlet pipe of the main mold is mixed with air in the mixing channel, and the gas outlet direction of the mixing channel is parallel to the gas outlet direction of the hydrogen outlet pipe of the main mold.

[0023] The mixed gases, under the action of the second sidewall, all flow to the hydrogen outlet pipe of the sub-mold, forming a reflux zone;

[0024] Hydrogen is ejected through the hydrogen outlet pipe of the secondary mold in a diffusion combustion manner, and combusted with the mixed gas in the circumferential recirculation zone to form a circumferential recirculation combustion mode.

[0025] As a preferred implementation, the following steps are also included:

[0026] In the air conditioning channel formed between the splitter plate and the corresponding splitter plate, which are respectively set parallel to the outer walls of the two diverter plates, the air entering the mixing channel is split.

[0027] By adjusting the angle of the rotatable guide vanes installed in the air conditioning channel, the airflow entering the mixing channel can be regulated.

[0028] As a preferred embodiment, the angle between the two first sidewalls and the second sidewall is 50°–75°. This angle setting optimizes the premixing effect of hydrogen and air in the mixing channel and the circumferential reflux mode.

[0029] As a preferred embodiment, the hydrogen outlet pipe of the sub-mold is located at the center of the second side wall, and both the hydrogen outlet pipe of the main mold and the hydrogen outlet pipe of the sub-mold are provided with several pipes along the height direction of the central blunt body.

[0030] Compared with the prior art, the beneficial effects of this invention are:

[0031] 1. High-efficiency mixing: Through the design of the central bluff body, guide plate, flow divider, and air conditioning and mixing channels, high-efficiency mixing of hydrogen and air can be achieved, so that hydrogen can fully contact air before combustion, obtain a uniform equivalence ratio distribution, reduce the hot spot temperature of the combustion zone, and reduce NOx emissions.

[0032] II. Stable Combustion: The circumferential recirculation combustion mode and the hydrogen outlet pipeline of the secondary mold ensure the stability of the combustion process, reduce the occurrence of flame instability, and improve the reliability of equipment operation.

[0033] 3. Flexible adjustment: The rotatable guide vanes in the air conditioning channel can flexibly adjust the air flow into the mixing channel, enabling the hydrogen combustion head to adapt to different combustion conditions and improving the equipment's versatility and adaptability.

[0034] IV. To prevent backfire: The gas outlet direction of the mixing channel is parallel to the gas outlet direction of the hydrogen outlet pipe of the main mold. The hydrogen outlet direction does not come into contact with the solid wall. There is no low-speed zone in the mixing channel to avoid backfire. Attached Figure Description

[0035] Figure 1 This is a schematic diagram of the overall three-dimensional structure of the present invention;

[0036] Figure 2 This is a top view of the structure of the present invention;

[0037] Figure 3 This is a front view structural diagram of the present invention;

[0038] Figure 4 for Figure 3 AA section view;

[0039] Figure 5 This is a schematic diagram of the air recirculation zone of the present invention.

[0040] Figure label:

[0041] 1. Central bluff body; 11. First sidewall; 12. Second sidewall; 13. Hydrogen inlet pipe; 14. Hydrogen outlet pipe of the main mold; 15. Hydrogen outlet pipe of the secondary mold;

[0042] 2. Drainage plate; 21. Mixing channel;

[0043] 3. Diverter plate; 31. Air conditioning channel. Detailed Implementation

[0044] The present invention will now be described in further detail with reference to the embodiments and accompanying drawings. However, this should not be construed as limiting the scope of the above-described subject matter of the present invention to the following embodiments; all technologies implemented based on the content of the present invention fall within the scope of the present invention.

[0045] Example 1, Reference Figure 1 , 2 3, 4, A circumferentially recirculating hydrogen combustion head with primary combustion premixing and secondary combustion diffusion, comprising a central blunt body 1 and two guide plates 2.

[0046] The central blunt body 1 includes two first sidewalls 11 and a second sidewall 12. The two first sidewalls 11 are symmetrically arranged about the center of the second sidewall 12 and are both inclined towards the second sidewall 12. A hydrogen inlet pipe 13 is provided at the top of the central blunt body 1 for introducing hydrogen. A main mold hydrogen outlet pipe 14 is provided on each of the two first sidewalls 11, and a secondary mold hydrogen outlet pipe 15 is provided on the second sidewall 12. Both the main mold hydrogen outlet pipe 14 and the secondary mold hydrogen outlet pipe 15 are connected to the hydrogen inlet pipe 13, so that hydrogen can flow out from the main mold hydrogen outlet pipe 14 and the secondary mold hydrogen outlet pipe 15 respectively.

[0047] Drainage plates 2: Two drainage plates 2 are respectively arranged parallel to the outer walls of the two first side walls 11, and the inner walls of the two drainage plates 2 and the outer walls of the two first side walls 11 form two mixing channels 21. The mixing channels 21 are used to mix hydrogen and air from the hydrogen outlet pipe 14 of the main mold, and the outlet direction of the mixing channels 21 is parallel to the outlet direction of the hydrogen outlet pipe 14 of the main mold to ensure that the flow direction of the mixed gas is consistent, which is beneficial to the subsequent combustion process.

[0048] refer to Figure 2 The hydrogen combustion head also includes two diverter plates 3, which are respectively arranged parallel to the outer walls of the two guide plates 2. The outer walls of the two guide plates 2 and the inner walls of the two diverter plates 3 form two air conditioning channels 31, which are used to divert the air entering the mixing channel 21, thereby allowing for preliminary adjustment of the amount of air entering the mixing channel 21.

[0049] To more precisely regulate the airflow entering the mixing channel 21, rotatable guide vanes are provided in the two air conditioning channels 31. By adjusting the angle of the guide vanes, the airflow entering the mixing channel 21 can be flexibly adjusted to adapt to different combustion conditions.

[0050] The central blunt body 1 has a triangular cross-sectional shape, with the two first sidewalls 11 and the second sidewall 12 forming an angle of 50°-75°. This angle setting is optimized to effectively improve the premixing effect of hydrogen and air in the mixing channel 21, while also positively promoting the circumferential reflux mode.

[0051] refer to Figure 3 , 4 The hydrogen outlet pipe 15 of the secondary mold is located at the center of the second side wall 12, and there are several hydrogen outlet pipes 14 of the main mold and hydrogen outlet pipes 15 of the secondary mold along the height direction of the central blunt body 1. This arrangement can make the hydrogen more evenly distributed and sprayed out, ensuring the stability and uniformity of combustion.

[0052] When using, please refer to the appendix. Figure 1 , 2 A central blunt body 1 is prepared, with a triangular cross-section. The angle between the two first sidewalls 11 and the second sidewall 12 is 60°. A hydrogen inlet pipe 13 is opened at the top of the central blunt body 1. Eleven main mold hydrogen outlet pipes 14 are evenly arranged on the two first sidewalls 11. Eleven secondary mold hydrogen outlet pipes 15 are arranged at the center of the second sidewall 12, and each pipe is connected to the hydrogen inlet pipe 13.

[0053] A flow guide plate 2 is installed parallel to the outer sidewalls of the two first sidewalls 11 to form a mixing channel 21; a flow divider plate 3 is installed parallel to the outer sidewalls of the two flow guide plates 2 to form an air conditioning channel 31, and a rotatable guide vane is installed in the air conditioning channel 31.

[0054] refer to Figure 5 Air is introduced from the intersection of the two first sidewalls 11, and hydrogen is introduced through the hydrogen inlet pipe 13. The hydrogen flows out from the main mold hydrogen outlet pipe 14 and the secondary mold hydrogen outlet pipe 15 respectively. The hydrogen flowing out of the main mold hydrogen outlet pipe 14 mixes with the air in the mixing channel 21. The mixed gas flows to the secondary mold hydrogen outlet pipe 15 under the action of the second sidewall 12, forming a reflux zone.

[0055] refer to Figure 5 The process of forming the reflux zone: As air is introduced from the top of the central blunt body 1, it is split by the two first sidewalls 11. Under the action of the second sidewall 12, the air cannot reach the bottom of the second sidewall 12, thus forming a low-pressure zone. Under the action of pressure, the mixed gas flows into the low-pressure zone, forming the reflux zone.

[0056] The secondary mold hydrogen outlet pipe 15 sprays hydrogen in a diffusion combustion manner, which is then burned with the mixed gas in the circumferential recirculation zone to ensure a more stable combustion flame. At the same time, the outlet direction of the mixing channel 21 is parallel to the outlet direction of the primary mold hydrogen outlet pipe 14, and the outlet direction of the hydrogen does not come into contact with the solid wall surface to avoid backfire.

[0057] By adjusting the angle of the guide vanes inside the air conditioning channel 31, the airflow entering the mixing channel 21 can be adjusted to adapt to different combustion requirements.

[0058] Example 2: A method for using a premixed main combustion and diffused secondary combustion circumferential recirculation hydrogen combustion head, based on the above-mentioned hydrogen combustion head, the specific steps are as follows:

[0059] Hydrogen introduction: Hydrogen is introduced through the hydrogen inlet pipe 13 at the top of the central blunt body 1, and the hydrogen flows out through the hydrogen outlet pipe 14 of the main mold and the hydrogen outlet pipe 15 of the secondary mold respectively.

[0060] Mixing process: Using the flow guide plates 2 located on the outer sidewalls of the two first sidewalls 11 of the central blunt body 1, the hydrogen flowing out of the hydrogen outlet pipe 14 of the main mold is mixed with air in the mixing channel 21, and the outlet direction of the mixing channel 21 is parallel to the outlet direction of the hydrogen outlet pipe 14 of the main mold, so as to achieve the initial premixing of hydrogen and air.

[0061] Recirculation zone formation: Under the action of the second sidewall 12, the mixed gases flow towards the hydrogen outlet pipe 15 of the sub-mold, forming a recirculation zone. During this process, the mixed gases further mix and diffuse within the recirculation zone, creating favorable conditions for combustion.

[0062] Combustion process: Hydrogen is ejected through the hydrogen outlet pipe 15 of the secondary mold in a diffusion combustion manner, and combusts with the mixed gas in the circumferential recirculation zone, forming a circumferential recirculation combustion mode. This combustion mode can make full use of the hydrogen and air mixture, improve combustion efficiency, and ensure combustion stability.

[0063] The above are merely 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 within the protection scope of the present invention.

Claims

1. A circumferentially recirculating hydrogen combustion head with primary combustion premixing and secondary combustion diffusion, characterized in that, include: A central blunt body (1) is provided with a second sidewall (12) and two first sidewalls (11). The two first sidewalls (11) are symmetrically arranged with respect to the second sidewall (12), and the two first sidewalls (11) are inclined towards the second sidewall (12). A hydrogen inlet pipe (13) is provided at the top of the central blunt body (1). A main mold hydrogen outlet pipe (14) is provided on each of the two first sidewalls (11). A secondary mold hydrogen outlet pipe (15) is provided on the second sidewall (12). The main mold hydrogen outlet pipe (14) and the secondary mold hydrogen outlet pipe (15) are both connected to the hydrogen inlet pipe (13). Two diversion plates (2) are respectively arranged parallel to the outer sidewalls of the two first sidewalls (11). The inner sidewalls of the two diversion plates (2) and the outer sidewalls of the two first sidewalls (11) form two mixing channels (21) for mixing hydrogen and air in the hydrogen outlet pipe (14) of the main mold. The outlet direction of the mixing channel (21) is parallel to the outlet direction of the hydrogen outlet pipe (14) of the main mold.

2. The main combustion premixed, secondary combustion diffusion circumferential recirculation hydrogen combustion head according to claim 1, characterized in that, Also includes: Two diverter plates (3) are respectively arranged parallel to the outer sidewalls of the two diverter plates (2). The outer sidewalls of the two diverter plates (2) and the inner sidewalls of the two diverter plates (3) form two air conditioning channels (31) for diverting the air entering the mixing channel (21).

3. The main combustion premixed, secondary combustion diffusion circumferential recirculation hydrogen combustion head according to claim 2, characterized in that, The two air conditioning channels (31) are equipped with rotatable guide vanes. By adjusting the angle of the guide vanes, the airflow into the mixing channel (21) can be regulated.

4. The main combustion premixed, secondary combustion diffusion circumferential recirculation hydrogen combustion head according to claim 1, characterized in that, The central blunt body (1) has a triangular cross-sectional shape, and the angle between the two first sidewalls (11) and the second sidewall (12) is 50°-75°.

5. The main combustion premixed, secondary combustion diffusion circumferential recirculation hydrogen combustion head according to claim 1, characterized in that, The secondary mold hydrogen outlet pipe (15) is located at the center of the second side wall (12), and both the main mold hydrogen outlet pipe (14) and the secondary mold hydrogen outlet pipe (15) are provided with several along the height direction of the central blunt body (1).

6. A method of using a circumferentially recirculating hydrogen combustion head with primary combustion premixing and secondary combustion diffusion, characterized in that, Based on the main combustion premixed, secondary combustion diffused circumferential recirculation hydrogen combustion head according to any one of claims 1-5, the following steps are included: Hydrogen gas is introduced through the hydrogen inlet pipe (13) at the top of the central blunt body (1), and the hydrogen gas flows out through the hydrogen outlet pipe (14) of the main mold and the hydrogen outlet pipe (15) of the secondary mold respectively. Using the flow guide plate (2) located on the outer side wall of the two first side walls (11) of the central blunt body (1), the hydrogen gas flowing out of the main mold hydrogen outlet pipe (14) is mixed with air in the mixing channel (21), and the gas outlet direction of the mixing channel (21) is parallel to the gas outlet direction of the main mold hydrogen outlet pipe (14). Under the action of the second sidewall (12), the mixed gas flows to the hydrogen outlet pipe (15) of the sub-mold, forming a reflux zone; Hydrogen is ejected through the hydrogen outlet pipe (15) of the secondary mold in a diffusion combustion manner, and combusted with the mixed gas in the circumferential recirculation zone to form a circumferential recirculation combustion mode.

7. The method of using the main combustion premixed, secondary combustion diffusion circumferential recirculation hydrogen combustion head according to claim 6, characterized in that, It also includes the following steps: In the air conditioning channel (31) formed between the diversion plate (3) which is parallel to the outer wall of the two diversion plates (2) and the corresponding diversion plate (2), the air entering the mixing channel (21) is diverted; By adjusting the angle of the rotatable guide vanes set in the air conditioning channel (31), the airflow rate entering the mixing channel (21) can be regulated.

8. The method of using the main combustion premixed, secondary combustion diffusion circumferential recirculation hydrogen combustion head according to claim 7, characterized in that, The angle between the two first sidewalls (11) and the second sidewall (12) is 50°-75°. This angle setting optimizes the premixing effect of hydrogen and air in the mixing channel (21) and the circumferential reflux mode.

9. The method of using the main combustion premixed, secondary combustion diffusion circumferential recirculation hydrogen combustion head according to claim 8, characterized in that, The secondary mold hydrogen outlet pipe (15) is located at the center of the second side wall (12), and both the main mold hydrogen outlet pipe (14) and the secondary mold hydrogen outlet pipe (15) are provided with several along the height direction of the central blunt body (1).

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