Hydrogen fuel nozzle head structure with hydrogen pressure stabilizing cavity

Abstract

The invention relates to the technical field of fuel nozzles, and discloses a hydrogen fuel nozzle head structure with a hydrogen pressure stabilizing cavity, the center of a head flow guide disc is provided with a cavity structure, the cavity structure can serve as the pressure stabilizing cavity to stabilize the pressure of injected hydrogen, and the pressure of hydrogen entering an air jet hole is stable; hydrogen and air can be mixed more uniformly; a whole circle of air jet holes are distributed in the radial direction, a whole circle of circumferential hydrogen channels are formed in the radial inner side and the radial outer side of each circle of air jet holes, each air jet hole is provided with a radial hydrogen jet hole in the vertical direction, and a multi-point direct injection structure is formed, so that the airflow speed is increased, the combustion flame stopping time is shortened, micro-mixing diffusion combustion is achieved, and the NOx emission amount is reduced. The hydrogen fuel nozzle head structure is based on the characteristic that hydrogen is wide and suitable for combustion, the lean oil flameout boundary of a combustion chamber can be widened, and the wider working range of an engine is achieved.

Description

Technical Field

[0001] The present invention relates to the technical field of fuel nozzles, and discloses a hydrogen fuel nozzle head structure with a hydrogen pressure stabilizing chamber. Background Art

[0002] Hydrogen energy is rich in sources, green and low-carbon, and widely used. It has the advantages of recyclability, zero emissions, energy storage, and energy interconnection. It is regarded as the cleanest energy with the most development potential in the 21st century and has attracted wide attention from countries around the world. Compared with traditional fuels, hydrogen fuels have physical characteristics such as strong compressibility, high combustion limit, high fuel calorific value, and high liquid hydrogen heat sink.

[0003] Hydrogen itself has strong compressibility. Compared with incompressible liquid aviation kerosene, uneven flow may occur in the actual supply of hydrogen. In addition, the density of hydrogen is extremely low, and the jet penetration is weak due to the small jet momentum, resulting in difficulty in mixing hydrogen / air. Based on the characteristics of low hydrogen density, large volume flow rate, fast diffusion speed, and high combustion calorific value, the traditional combustion chamber head structure is not suitable for hydrogen fuels. Summary of the Invention

[0004] The purpose of the present invention is to provide a hydrogen fuel nozzle head structure with a hydrogen pressure stabilizing chamber, which can ensure relatively stable pressure of hydrogen entering the air jet holes while enabling more uniform mixing of hydrogen and air; the head deflector adopts a multi-point direct injection structure form, which can shorten the combustion flame residence time, achieve micro-mixing diffusion combustion, and reduce NOx emissions.

[0005] In order to achieve the above technical effects, the technical solution adopted by the present invention is:

[0006] A hydrogen fuel nozzle head structure with a hydrogen pressure stabilizing chamber, comprising:

[0007] A head deflector, the head deflector is of an annular structure, and a cavity is provided along the axis direction of the head deflector at the center of the head deflector, and the cavity is communicated with a hydrogen supply pipeline;

[0008] A circumferential hydrogen channel, the circumferential hydrogen channel is of an integral-ring sealed runway type structure, the number of the circumferential hydrogen channels is multiple, and the multiple circumferential hydrogen channels are distributed at intervals in the radial direction on the outer periphery of the cavity;

[0009] A first hydrogen passage hole for communicating the cavity with the circumferential hydrogen channel close to the cavity;

[0010] A second hydrogen passage hole for communicating two adjacent circumferential hydrogen channels;

[0011] Air holes are provided on the head deflector plate. First-stage air holes are provided between two adjacent circumferential hydrogen channels. Each stage of air holes includes a plurality of air jet holes penetrating through the intake side and the exhaust side of the head deflector plate, and the plurality of air jet holes are evenly distributed circumferentially; each air jet hole communicates with the adjacent circumferential hydrogen channel through a radially arranged radial hydrogen jet hole.

[0012] Further, the number of the first hydrogen holes is multiple, and the multiple first ventilation holes are evenly distributed circumferentially. Each first hydrogen hole is arranged radially along the head deflector plate.

[0013] Further, the range of the tangential angle between the jet direction at the outlet of each radial hydrogen jet hole and the corresponding air jet hole is 30° to 90°.

[0014] Further, the number of the second hydrogen holes is multiple, and the multiple second hydrogen holes are evenly distributed circumferentially. Each second hydrogen hole is arranged radially along the head deflector plate.

[0015] Further, the number of the second hydrogen holes is the same as the number of air jet holes of the corresponding stage of air holes, and one second hydrogen hole is provided between two adjacent air jet holes of the same stage of air holes.

[0016] Further, each air jet hole communicates with the adjacent second hydrogen hole through a circumferentially arranged circumferential hydrogen jet hole.

[0017] Further, the range of the tangential angle between the jet direction at the outlet of each circumferential hydrogen jet hole and the corresponding air jet hole is 30° to 90°.

[0018] Further, the cross-sectional shape of the air jet hole is rectangular or circular.

[0019] Further, an air cooling channel (10) is also arranged circumferentially on the head deflector plate. The air cooling channel extends from the intake side of the head deflector plate to a position close to the exhaust side. A plurality of air cooling holes are provided on the exhaust side of the head deflector plate, and each air cooling hole communicates with the air cooling channel.

[0020] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0021] 1. The center of the head deflector disk of the present invention has a cavity structure, which can be used as a pressure stabilizing cavity to stabilize the injected hydrogen pressure. While ensuring relatively stable pressure of hydrogen entering the air jet holes, it can also make the mixing of hydrogen and air more uniform; a whole circle of air jet holes is radially distributed, and there are whole circles of circumferential hydrogen channels on both the radial inner and outer sides of each circle of air jet holes. Each air jet hole is provided with a radial hydrogen jet hole in the vertical direction, forming a multi-point direct injection structure, increasing the air flow velocity, shortening the combustion flame residence time, realizing micro-mixing diffusion combustion, and reducing NOx emissions;

[0022] 2. Based on the wide flammability characteristics of hydrogen, the head structure of the hydrogen fuel nozzle of the present invention can broaden the lean blowout boundary of the combustion chamber and achieve a wider working range of the engine; in addition, due to the short combustion flame of hydrogen, the axial dimension of the combustion chamber can be greatly shortened, thereby reducing the weight of the combustion chamber and the flight fuel consumption of the engine. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 is a three-dimensional view of the head structure of the hydrogen fuel nozzle with a hydrogen pressure stabilizing cavity in Embodiment 1 or 2;

[0024] Figure 2 is a schematic view of the head structure of the hydrogen fuel nozzle with a hydrogen pressure stabilizing cavity in Embodiment 1 or 2;

[0025] Figure 3 is a schematic view of the internal structure of the head deflector disk in Embodiment 1 or 2;

[0026] Figure 4 is a schematic view of the head deflector disk structure with a cavity cooling channel in Embodiment 2;

[0027] Wherein, 1. Head deflector disk; 2. Cavity; 3. Hydrogen supply pipeline; 4. Circumferential hydrogen channel; 5. First hydrogen passing hole; 6. Second hydrogen passing hole; 7. Air jet hole; 8. Radial hydrogen jet hole; 9. Circumferential hydrogen jet hole; 10. Air cooling channel; 11. Air cooling hole. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0028] The present invention will be further described in detail below in conjunction with the embodiments and the drawings. However, it should not be understood that the scope of the above-mentioned subject matter of the present invention is limited to the following embodiments. All technologies implemented based on the content of the present invention belong to the scope of the present invention.

[0029] Embodiment 1

[0030] See Figures 1 - 3 , a head structure of a hydrogen fuel nozzle with a hydrogen pressure stabilizing cavity, comprising:

[0031] The head flow deflector 1, the head flow deflector 1 is of an annular structure, and a cavity 2 is provided along the axis direction of the head flow deflector 1 at the center of the head flow deflector 1. The cavity 2 is communicated with the hydrogen supply pipeline 3;

[0032] The circumferential hydrogen channel 4, the circumferential hydrogen channel 4 is of an integral ring sealed runway type structure, and the number of the circumferential hydrogen channels 4 is multiple. The multiple circumferential hydrogen channels 4 are distributed at intervals along the radial direction on the outer periphery of the cavity 2;

[0033] The first hydrogen injection hole 5 is used to communicate the cavity 2 with the circumferential hydrogen channel 4 close to the cavity 2;

[0034] The second hydrogen injection hole 6 is used to communicate two adjacent circumferential hydrogen channels 4;

[0035] The air holes, the air holes are arranged on the head flow deflector 1. Primary air holes are arranged between two adjacent circumferential hydrogen channels 4. Each stage of the air holes includes a plurality of air jet holes 7 penetrating through the intake side and the exhaust side of the head flow deflector 1. The plurality of air jet holes 7 are evenly distributed along the circumferential direction; A radial hydrogen jet hole 8 arranged along the radial direction is communicated between each air jet hole 7 and the adjacent circumferential hydrogen channel 4.

[0036] In this embodiment, the center of the head flow deflector 1 has a cavity 2 structure, which can be used as a pressure stabilizing cavity to stabilize the injected hydrogen pressure. While ensuring that the pressure of the hydrogen entering the air jet hole 7 is relatively stable, it can also make the hydrogen and air mix more evenly; The air jet holes 7 are distributed in a whole circle radially. There are whole circles of circumferential hydrogen channels 4 on both the radial inner and outer sides of each circle of air jet holes 7. Each air jet hole 7 is provided with a radial hydrogen jet hole 8 in the vertical direction, forming a multi-point direct injection structure, increasing the air flow velocity, shortening the residence time of the combustion flame, realizing micro-mixing diffusion combustion, and reducing the NOx emission; Based on the wide flammability characteristics of hydrogen, the lean blowout boundary of the combustion chamber can be widened, and a wider working range of the engine can be realized; In addition, due to the short combustion flame of hydrogen, the axial dimension of the combustion chamber can be greatly shortened, thereby reducing the weight of the combustion chamber and the flight fuel consumption of the engine.

[0037] In this embodiment, the number of the first hydrogen injection holes 5 is multiple. The multiple first ventilation holes are evenly distributed along the circumferential direction. Each first hydrogen injection hole 5 is arranged along the radial direction of the head flow deflector 1. It can make the air and hydrogen mix well, the flame uniformity is good, and the risk of flashback is reduced.

[0038] Embodiment 2

[0039] See Figures 1 - 4, a hydrogen fuel nozzle head structure with a hydrogen pressure stabilizing chamber. The main body of the combustion chamber head in this embodiment is an annular head deflector 1. Along the axial direction at the center of the head deflector 1, there is a relatively large cavity 2 as the pressure stabilizing chamber in its center, which is used to stabilize the injected hydrogen pressure.

[0040] The combustion chamber head has multiple stages of air holes. Each circle is a stage of air holes. The one with the smallest overall diameter is the first stage, and the outer circle is the second stage, and so on. The head deflector 1 in this embodiment includes two stages of air holes. Each stage of air holes includes multiple air jet holes 7 evenly distributed circumferentially. In this embodiment, each stage of air holes has sixteen air jet holes 7. The shape of the air holes can be circular, square or other shapes. It should be noted that the number of air jet holes 7 on each stage of air holes can be different, but the number of air jet holes 7 on each stage of air holes is the same as the number of the second hydrogen injection holes 6 at the corresponding stage position.

[0041] In this embodiment, a circumferential hydrogen channel 4 is formed in a circle on the radial inner side and outer side of each stage of air holes. A stage of air holes is arranged between two adjacent circumferential hydrogen channels 4. That is, if the number of circles of air holes is N, then the number of circles of circumferential hydrogen channels 4 is N + 1. The air holes in this embodiment are two stages, and the circumferential hydrogen channels 4 are three circles. The circumferential hydrogen channel 4 is a closed runway-shaped structure of a complete ring. The cavity 2 and the circumferential hydrogen channel 4 close to the cavity 2 are connected through the first hydrogen injection hole 5, and two adjacent circumferential hydrogen channels 4 are connected through the second hydrogen injection hole 6, so that all circumferential hydrogen channels 4 are connected and the pressure is the same.

[0042] In this embodiment, the number of air jet holes 7 in each stage is the same as the number of the second hydrogen injection holes 6 at the corresponding stage. A second hydrogen injection hole 6 is arranged between two adjacent air jet holes 7 in the same stage of air holes.

[0043] Two radial hydrogen jet holes 8 and two circumferential hydrogen jet holes 9 are arranged in each air hole jet hole. Each air jet hole 7 is connected to the adjacent second hydrogen injection hole 6 through the circumferentially arranged circumferential hydrogen jet hole 9; the four hydrogen jet holes are respectively located in the middle positions at the edges of the air hole jet hole, and hydrogen is sprayed simultaneously from four directions. The outlet ends of the two radial hydrogen jet holes 8 and the two circumferential hydrogen jet holes 9 can be adjusted according to the design (in this embodiment, the tangential included angle range between the outlet spraying direction of each circumferential hydrogen jet hole 9 and the corresponding air jet hole 7 is 30° to 90°), so as to generate air swirl mixing in multiple directions and ensure more uniform mixing of air and hydrogen. The channel area of the air holes is larger than that of the radial hydrogen jet holes 8 and the circumferential hydrogen jet holes 9.

[0044] Hydrogen enters the cavity 2 of the head deflector disk 1 through the hydrogen supply pipeline 3. After ensuring the stability of the hydrogen pressure, it supplies hydrogen to the first-stage circumferential hydrogen channel 4 through the first hydrogen supply hole 5, and then supplies hydrogen to the second-stage circumferential hydrogen channel 4 and the third-stage circumferential hydrogen channel 4 respectively through the second hydrogen supply hole 6, so as to ensure that hydrogen flows into all the circumferential hydrogen channels 4.

[0045] In this embodiment, due to the complex hydrogen channels inside the nozzle and most of the hydrogen jet holes and hydrogen channels being inside, the head structure of this hydrogen fuel combustion chamber can be processed by additive manufacturing or a combination of additive and subtractive manufacturing.

[0046] During use, the mainstream air K1 flows into the air jet hole 7 from the intake side of the head deflector disk 1 along the horizontal direction or the axis direction of the head deflector disk 1. Hydrogen H1 enters the cavity 2 through the hydrogen supply pipeline 3. After ensuring the stability of the hydrogen pressure, it supplies hydrogen to the first-stage circumferential hydrogen channel 4 through the first hydrogen supply hole 5, and supplies hydrogen to the second-stage circumferential hydrogen channel 4 and the third-stage circumferential hydrogen channel 4 respectively through the second hydrogen supply hole 6, so as to ensure that hydrogen flows into all the circumferential hydrogen channels 4. During this process, hydrogen is injected into the corresponding air jet holes 7 from four directions through the radial hydrogen jet holes 8 and the circumferential hydrogen jet holes 9. Through the multi-point transverse jet micro-mixing form, hydrogen is fully mixed with the air in the air jet hole 7, improving the combustion efficiency, reducing the risk of flashback, and significantly reducing the NOx emissions.

[0047] To address the problem of high temperature and easy ablation in the central area of the nozzle head, a multi-point micro-hole air cooling structure can be designed on the head deflector disk 1. In this embodiment, an air cooling channel 10 is provided between the cavity 2 and the circumferential hydrogen channel 4 close to the cavity 2. The cooling channel extends from the intake side of the head deflector disk 1 to a position close to the exhaust side. A plurality of air cooling holes 11 are opened on the exhaust side of the head deflector disk 1, and each air cooling hole 11 communicates with the air cooling channel 10. During use, a part of the mainstream air flows into the air cooling channel 10 from the intake side of the head deflector disk 1 along the horizontal direction or the axis direction, and then is ejected outward through a plurality of small air cooling holes 11, so that the air quickly sprays out from the head deflector disk 1, promoting the combustion gas at the head to flow downstream of the combustion chamber, having a certain cooling effect on the head, and preventing ablation of the nozzle head of the combustion chamber. The air cooling channel 10 and the air cooling holes in this embodiment can be in multiple groups. For example, a circle of air cooling channel 10 and air cooling holes 11 can also be provided on the outer ring of the nozzle to cool the temperature of the outer layer of the flame and reduce the thermal shock of the hydrogen combustion flame on the flame tube of the combustion chamber.

[0048] The above are only the 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 shall be included within the protection scope of the present invention.

Claims

1. A hydrogen fuel nozzle head structure with a hydrogen pressure stabilization cavity, characterized in that, Comprising: A head flow guiding disc (1), the head flow guiding disc (1) being of an annular structure, a cavity (2) being provided along the axis direction of the head flow guiding disc (1) at the center of the head flow guiding disc (1), and the cavity (2) being communicated with a hydrogen supply pipeline (3); A circumferential hydrogen channel (4), the circumferential hydrogen channel (4) being of an integral ring sealed runway type structure, the number of the circumferential hydrogen channels (4) being multiple, and the multiple circumferential hydrogen channels (4) being distributed at intervals in the radial direction on the outer periphery of the cavity (2); A first hydrogen passing hole (5) for communicating the cavity (2) with the circumferential hydrogen channel (4) close to the cavity (2); A second hydrogen passing hole (6) for communicating two adjacent circumferential hydrogen channels (4); Air holes, the air holes being arranged on the head flow guiding disc (1), a first-stage air hole being arranged between two adjacent circumferential hydrogen channels (4), each stage of the air holes including a plurality of air jet holes (7) penetrating through the intake side and the exhaust side of the head flow guiding disc (1), and the plurality of air jet holes (7) being evenly distributed in the circumferential direction; a radial hydrogen jet hole (8) arranged in the radial direction is provided between each air jet hole (7) and the adjacent circumferential hydrogen channel (4).

2. The hydrogen fuel nozzle head structure with a hydrogen pressure stabilizing chamber according to claim 1, characterized in that, The number of the first hydrogen passing holes (5) is multiple, the multiple first hydrogen passing holes are evenly distributed in the circumferential direction, and each first hydrogen passing hole (5) is arranged in the radial direction of the head flow guiding disc (1).

3. The hydrogen fuel nozzle head structure with a hydrogen pressure stabilizing cavity according to claim 1, characterized in that, The jetting direction at the outlet of each radial hydrogen jet hole (8) forms a tangential angle range of 30° to 90° with the corresponding air jet hole (7).

4. The hydrogen fuel nozzle head structure with a hydrogen pressure stabilizing cavity according to claim 1, characterized in that, The number of the second hydrogen passing holes (6) is multiple, the multiple second hydrogen passing holes (6) are evenly distributed in the circumferential direction, and each second hydrogen passing hole (6) is arranged in the radial direction of the head flow guiding disc (1).

5. The head structure of the hydrogen fuel nozzle with a hydrogen pressure stabilizing cavity according to claim 4, characterized in that, The number of the second hydrogen passing holes (6) is the same as the number of the air jet holes (7) of the corresponding stage of air holes, and a second hydrogen passing hole (6) is arranged between two adjacent air jet holes (7) of the same stage of air holes.

6. The head structure of the hydrogen fuel nozzle with a hydrogen pressure stabilizing cavity according to claim 5, characterized in that, A circumferential hydrogen jet hole (9) arranged in the circumferential direction is provided between each air jet hole (7) and the adjacent second hydrogen passing hole (6).

7. The head structure of the hydrogen fuel nozzle with a hydrogen pressure stabilizing cavity according to claim 6, characterized in that, The jetting direction at the outlet of each circumferential hydrogen jet hole (9) forms a tangential angle range of 30° to 90° with the corresponding air jet hole (7).

8. The head structure of the hydrogen fuel nozzle with a hydrogen pressure stabilizing cavity according to claim 1, characterized in that, The cross-sectional shape of the air jet hole (7) is rectangular or circular.

9. The hydrogen fuel nozzle head structure with a hydrogen pressure stabilizing cavity according to claim 1, characterized in that, An air cooling channel (10) is further arranged on the head flow guiding disc (1) in the circumferential direction, the air cooling channel (10) extends from the intake side of the head flow guiding disc (1) to a position close to the exhaust side, and a plurality of air cooling holes (11) are opened on the exhaust side of the head flow guiding disc (1), and each air cooling hole (11) is communicated with the air cooling channel (10).

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