Afterburner hydrogen supply structure

Abstract

The afterburner hydrogen supply structure comprises a fuel header pipe assembly and a stabilizer, and the fuel header pipe assembly is connected with the stabilizer through a first connecting supporting pipe and a second connecting supporting pipe. The multi-path fuel header pipe with the rigid connecting rod of the structure can flexibly adjust fuel supply in the transient state of ignition, the middle working condition and the full working condition and in the variable working condition, and the Y-shaped flame stabilizer can achieve low-blockage-ratio, efficient and stable combustion under the condition of the large bypass ratio. The fuel header pipe and the flame stabilizer are rigidly connected through the ignition connection supporting pipe, and meanwhile the ignition fuel multi-point distribution supply and integrated connection requirements are met. And the combustion stability and the temperature distribution uniformity are good, the structural manufacturability is good, violent mechanical vibration is not prone to occurring, the assembly precision is high, and array arrangement can be achieved according to requirements.

Description

Technical Field

[0001] This invention belongs to the field of aero-engine technology, and particularly relates to a hydrogen supply structure for an afterburner. Background Technology

[0002] Due to hydrogen's excellent cooling properties and wide combustible range, hydrogen-powered fighter jets offer superior economy, a wider operating envelope, and greater thrust-to-weight ratio compared to fighter jets using conventional aviation kerosene, while also having a lower fuel consumption rate. The hydrogen-fueled afterburner is a key component that further enhances its combat effectiveness.

[0003] Although hydrogen possesses a high flame propagation speed and diffusion coefficient, under the operating conditions of an afterburner, its flame propagation speed is insufficient to match the high-speed incoming flow, making it difficult to form a stationary flame. Furthermore, when the afterburner has a large bypass ratio, hydrogen combustion is prone to incomplete radial combustion, resulting in uneven temperature distribution and difficulty in ensuring dynamic combustion stability under various operating conditions (ignition, intermediate, full-range, etc.) and transient variable conditions. In addition, from a structural and manufacturability perspective, current afterburners often manufacture the fuel supply lines and stabilizers separately and assemble them into the engine, leading to lower dimensional accuracy in the relative positions of the fuel injection and stabilizers, making them prone to misalignment. Moreover, assembling the fuel supply lines and stabilizers separately into the engine requires separate connecting rod suspension structures, resulting in lower assembly accuracy, more complex structures, poorer rigidity, a higher probability of mechanical vibration, and increased susceptibility to damage. In summary, hydrogen-fueled afterburners face both combustion stability issues under varying operating conditions and structural and manufacturability challenges.

[0004] Patent application CN113701188A discloses an evaporative stabilizer structure with a separate housing and carburetor, as well as a separate evaporator tube and housing. This non-integrated design results in lower rigidity, lower installation precision, and a more complex assembly process. Furthermore, the patent application does not consider fuel supply distribution under various operating conditions; its power source is fuel oil, and the afterburner efficiency is less than 90%.

[0005] Patent document with announcement number WO2023243434A1 discloses a hydrogen burner, hydrogen burner system, jet engine and power generation device that can maintain a hydrogen flame over a wide operating range. Although it is equipped with a hydrogen supply pipe and injector structure, the technology is used to suppress the generation of nitrogen oxides associated with local high-temperature combustion and prevent reverse phenomena. Summary of the Invention

[0006] To solve the above-mentioned technical problems, the present invention provides an afterburner hydrogen supply structure.

[0007] The present invention is achieved through the following technical solutions.

[0008] The present invention provides a hydrogen supply structure for an afterburner, including a fuel main assembly and a stabilizer, wherein the fuel main assembly is connected to the stabilizer through a first connecting support pipe and a second connecting support pipe; The fuel manifold assembly includes a first fuel manifold, a second fuel manifold, and a third fuel manifold. The second fuel manifold is disposed between the first fuel manifold and the third fuel manifold. The third fuel manifold is disposed between the second fuel manifold and the stabilizer. The first fuel manifold, the second fuel manifold, and the third fuel manifold are connected and fastened together by a connecting rod.

[0009] Preferably, a first connecting pipe and a second connecting pipe are provided below the third fuel main pipe. The first connecting pipe and the second connecting pipe are respectively connected to the bottom of the third fuel main pipe. The first connecting pipe is connected to the stabilizer through the first connecting support pipe and the second connecting support pipe, and the second connecting pipe is connected to the stabilizer through the first connecting support pipe and the second connecting support pipe.

[0010] Preferably, the fuel header spacing D formed by the first fuel header, the second fuel header, and the third fuel header is... ft It needs to be greater than 1.5 times the maximum diameter of the first, second, and third fuel headers, and the distance D from the third fuel header to the stabilizer. tfh fuel mains spacing D ft More than 1.5 times that.

[0011] A third connecting pipe and a fourth connecting pipe are provided on the first fuel main pipe. The length of the third connecting pipe is greater than the length of the fourth connecting pipe. Fuel holes are provided on the third connecting pipe and the fourth connecting pipe respectively. The third connecting pipe and the fourth connecting pipe are respectively connected to the bottom of the first fuel main pipe. The spacing of the fuel holes on the third connecting pipe is greater than the spacing of the fuel holes on the fourth connecting pipe.

[0012] Preferably, the height H of the first fuel manifold ft It needs to be greater than 2 / 3 of the stabilizer's maximum height, which is H. efh +H ifh .

[0013] Preferably, the stabilizer includes an inner radial stabilizer, a central circumferential stabilizer, and an outer radial stabilizer. The inner radial stabilizer is internally connected to the central circumferential stabilizer and the outer radial stabilizer. One end of the central circumferential stabilizer is connected to the inner radial stabilizer, and the other end is connected to the outer radial stabilizer. The inner radial stabilizer is connected to the fuel manifold assembly through a second connecting support pipe. The central circumferential stabilizer is connected to the fuel manifold assembly through a first support pipe. The outer radial stabilizer is connected to the fuel manifold assembly through a second connecting support pipe.

[0014] Preferably, the radial stabilizer is provided with a first nozzle, the second connecting support tube communicates with the first nozzle, and the axial expansion angle θ of the radial stabilizer is... rfh The range is 10~30°.

[0015] Preferably, a second nozzle is provided on the central circumferential stabilizer, and the first support tube communicates with the second nozzle. The axial expansion angle θ of the central circumferential stabilizer is... cfh The range is 10~30°.

[0016] Preferably, a third nozzle is provided on the outer duct radial stabilizer, and the second connecting support pipe is connected to the third nozzle.

[0017] Preferably, the axial expansion angle θ of the outer bypass radial stabilizer efh The range is 10~30°.

[0018] The beneficial effects of this invention are as follows: This invention is applicable to high-bypass afterburner chambers, ensuring stable ignition and combustion under ignition, intermediate, and full operating conditions. It also maintains stable combustion during transient changes in operating conditions, achieving a hydrogen combustion efficiency of over 96%. Furthermore, it maintains good temperature uniformity when facing both low-temperature, high-speed inflow from the outer bypass and high-temperature, low-oxygen, high-speed inflow from the inner bypass. Its structure is easy to manufacture and assemble, ensuring high precision in key dimensions related to combustion organization and minimizing the risk of severe mechanical vibration. It exhibits good adaptability to aero-engine structures of different sizes, contains no complex and minute geometric surfaces, and can be geometrically scaled and arrayed as a single unit as required. Attached Figure Description

[0019] Figure 1 This is a schematic diagram of the structure of the present invention; Figure 2 This is a schematic diagram of the stabilizer of the present invention; Figure 3 yes Figure 2 AA cross-section view; Figure 4 yes Figure 3 BB cross-section; Figure 5 yes Figure 2 CC cross-section; Figure 6 yes Figure 2 DD cross-section; In the diagram: 1-First fuel main, 11-Third connecting pipe, 12-Fourth connecting pipe, 13-Fuel port, 2-Second fuel main, 3-Third fuel main, 31-First connecting pipe, 32-Second connecting pipe, 4-Support pipe, 5-Second connecting support pipe, 6-Inner radial stabilizer, 61-First nozzle, 7-Central circumferential stabilizer, 71-Second nozzle, 8-Outer radial stabilizer, 81-Third nozzle, 9-Connecting rod. Detailed Implementation

[0020] The technical solution of the present invention is further described below, but the scope of protection is not limited to what is described.

[0021] Example: like Figures 1 to 6 As shown, an afterburner hydrogen supply structure includes a fuel main assembly and a stabilizer. The fuel main assembly is connected to the stabilizer through a first connecting support pipe 4 and a second connecting support pipe 5. The fuel manifold assembly includes a first fuel manifold 1, a second fuel manifold 2, and a third fuel manifold 3. The second fuel manifold 2 is disposed between the first fuel manifold 1 and the third fuel manifold 3. The third fuel manifold 3 is disposed between the second fuel manifold 2 and the stabilizer. The first fuel manifold 1, the second fuel manifold 2, and the third fuel manifold 3 are connected and fastened together by a connecting rod 9.

[0022] Below the third fuel main pipe 3, a first connecting pipe 31 and a second connecting pipe 32 are provided. The first connecting pipe 31 and the second connecting pipe 32 are respectively connected to the bottom of the third fuel main pipe 3. The first connecting pipe 31 is connected to the stabilizer through the first connecting support pipe 4 and the second connecting support pipe 5, respectively. The second connecting pipe 32 is connected to the stabilizer through the first connecting support pipe 4 and the second connecting support pipe 5, respectively. The length of the first connecting pipe 31 is greater than the length of the second connecting pipe 32. No fuel holes 13 are provided on the first connecting pipe 31 and the second connecting pipe 32.

[0023] The fuel header spacing D formed by the first fuel header 1, the second fuel header 2, and the third fuel header 3 ft It needs to be greater than 1.5 times the maximum diameter of the first fuel manifold 1, the second fuel manifold 2, and the third fuel manifold 3, and the distance D from the third fuel manifold 3 to the stabilizer. tfh fuel mains spacing D ft More than 1.5 times that of the first fuel main 1. The second fuel main 2 is located downstream of the first fuel main 1, and the third fuel main 3 is located downstream of the second fuel main 2. The forms of the first fuel main 1, the second fuel main 2, and the third fuel main 3 are consistent with the combustion organization method.

[0024] A third connecting pipe 11 and a fourth connecting pipe 12 are provided on the first fuel main pipe 1. The length of the third connecting pipe 11 is greater than the length of the fourth connecting pipe 12. Fuel holes 13 are symmetrically and evenly distributed on the third connecting pipe 11 and the fourth connecting pipe 12. The third connecting pipe 11 and the fourth connecting pipe 12 are respectively connected to the bottom of the first fuel main pipe 1. The spacing D of the fuel holes 13 on the third connecting pipe 11 is... flt The spacing D of the fuel holes 13 on the fourth connecting pipe 12 is greater than that of the fourth connecting pipe 12. fst Fuel hole 13 has a diameter of 1~6mm and a spacing of D. flt The spacing is 5~15mm, and the distance D is... fst The diameter is 3~12mm, ensuring a hydrogen injection velocity of 100~250m / s. The specific value is set according to the actual situation to ensure sufficient penetration depth of the hydrogen transverse jet in the mainstream airflow, preventing combustion after the fuel main pipe, and ensuring that the array hydrogen transverse jet is blown off and then entrained in the stabilizer recirculation zone. The total number of fuel holes 13 N in the third connecting pipe 11 and the fourth connecting pipe 12 is... ft The number of fuel holes 13 on the third connecting pipe 11 is 20~60, and the number of fuel holes 13 on the third connecting pipe 11 is greater than the number of fuel holes 13 on the fourth connecting pipe 12.

[0025] The first fuel main 1 and the second fuel main 2 have the same structure.

[0026] The height H of the first fuel manifold 1 ft It needs to be greater than 2 / 3 of the maximum height of the stabilizer. The maximum height of the stabilizer is the height H of the outer bypass radial stabilizer 8. efh +Inner radial stabilizer 6 height H ifh This ensures radial fuel and air matching, while the lowest end face of the first fuel manifold 1 must not touch the cone inside the afterburner. The first fuel manifold 1 is located downstream of the outlet of the afterburner's inner and outer bypass louver mixer and is asymmetrically shaped "π". The axis of the fuel orifice 13 is perpendicular to both the axis of the first fuel manifold 1 and the mainstream direction of the incoming flow.

[0027] From a geometric and positional perspective, the second fuel header 2 can be derived from the first fuel header 1 by adjusting the fuel header arrangement angle θ. ft The array is formed downstream of the afterburner, and the spacing D of the fuel header after the array is formed. ft It needs to be 1.5 times larger than the thickest diameter of the second fuel main 2.

[0028] From a geometric and positional perspective, the third fuel header 3 is also derived from the second fuel header 2 by an inclination angle θ of the fuel header arrangement. ft The array is formed downstream of the afterburner, and the spacing D of the fuel header after the array is formed. ft It needs to be greater than 1.5 times the largest diameter of the third fuel manifold 3, and the distance D from the third fuel manifold 3 to the stabilizer. tfh fuel mains spacing D ftMore than 1.5 times that of the other fuel. Ultimately, the guiding effect formed by the three fuel headers is beneficial for guiding the flow of fuel through the afterburner heat shield.

[0029] The stabilizer includes an inner radial stabilizer 6, a central circumferential stabilizer 7, and an outer radial stabilizer 8. The inner radial stabilizer 6 is internally connected to the central circumferential stabilizer 7 and the outer radial stabilizer 8. The three are integrated and arranged in an asymmetrical Y-shaped structure. One end of the central circumferential stabilizer 7 is connected to the inner radial stabilizer 6, and the other end is connected to the outer radial stabilizer 8. The inner radial stabilizer 6 is connected to the fuel manifold assembly through a second connecting support pipe 5. The central circumferential stabilizer 7 is connected to the fuel manifold assembly through a first support pipe 4. The outer radial stabilizer 8 is connected to the fuel manifold assembly through a second connecting support pipe 5. The inner radial stabilizer 6 and the outer radial stabilizer 8 are arranged vertically, while the central circumferential stabilizer 7 is arranged horizontally. There is one inner radial stabilizer 6 and two outer radial stabilizers 8, each connected to the top of the central circumferential stabilizer 7. The first connecting pipe 31 is located on the side of the inner radial stabilizer 6. The first connecting pipe 31 is connected to the central circumferential stabilizer 7 through the first support pipe 4, which is inserted axially into the center of the central circumferential stabilizer 7. The upper part is connected to the outer radial stabilizer 8 through the second connecting support pipe 5, and the lower part is connected to the inner radial stabilizer 6 through the second connecting support pipe 5. The two second connecting support pipes 5 are inserted axially into the centers of the outer radial stabilizer 8 and the inner radial stabilizer 6, respectively. The second connecting pipe 32 is located on the side where only the outer radial stabilizer 8 is located. The upper part is connected to the outer radial stabilizer 8 through the second connecting support pipe 5, and the lower part is connected to the central circumferential stabilizer 7 through the first support pipe 4. The structural distribution of the corresponding first connecting pipe 31 and second connecting pipe 32 on the first fuel main pipe 1 and the second fuel main pipe 2 is the same as that on the third fuel main pipe 3, but neither is connected to the first connecting support pipe 4 or the second connecting support pipe 5.

[0030] In ignition mode and above, hydrogen fuel is introduced into the third fuel main pipe 3. The hydrogen fuel is then injected axially into the stabilizer through the first support pipe 4 and the second connecting support pipe 5. The injection speed is controlled at 20~60m / s to avoid dispersing the backflow area after the stabilizer.

[0031] The first connecting support pipe 4 is the center ignition connecting support pipe. It connects the third fuel main pipe 3 and the center circumferential stabilizer 7. During ignition and above, hydrogen is drawn from the third fuel main pipe 3 and ejected through the second nozzle 71. It also serves as the main rigid connecting support structure for the stabilizer and fuel main pipe assembly. The diameter of the second nozzle 71 is 5-20 mm. The diameter of the first connecting support pipe 4 must match the diameter of the second nozzle 71 to form an expanding structure for the fuel nozzle. The wall thickness of the first connecting support pipe 4 is at least 1 mm to ensure sufficient rigidity. The stabilizer fuel nozzle expansion angle θ is also specified. ffhThe angles are all 30~60°, which is beneficial for the radial distribution of ignition fuel. After hydrogen is directly introduced into the stabilizer, a standby fuel distribution can be formed, and it is directly injected into the front stagnation point of the recirculation zone, avoiding premature diffusion of ignition fuel and ensuring ignition reliability.

[0032] The second connecting support pipe 5 is a radial ignition connecting support pipe. During ignition and above, hydrogen is drawn from the third fuel main pipe 3 and ejected through the first nozzle 61 and the third nozzle 81. It also serves as a secondary rigid connecting support structure for the stabilizer and fuel main pipe assembly. The diameters of the first nozzle 61 and the third nozzle 81 are 3~15mm, smaller than the diameter of the second nozzle 71. The diameter of the second connecting support pipe 5 must match the diameters of the first nozzle 61 and the third nozzle 81 to form an expanded structure for the fuel nozzles. The wall thickness of the second connecting support pipe 5 should be at least 1mm to ensure sufficient rigidity. Simultaneously injecting hydrogen into the inner radial stabilizer 6 and the outer radial stabilizer 8 can meet the radial temperature distribution requirements after ignition, improving the probability of successful ignition. Directly injecting hydrogen into the pre-stagnant point of the recirculation zone avoids premature diffusion of the ignition fuel, ensuring ignition reliability. The spacing D between the third nozzles 81 on the outer radial stabilizer 8... fe The distance D between the first nozzle 61 on the radial stabilizer 6 and the inner diameter of the radial stabilizer 6 fi All are outer bypass radial stabilizers with a height of 8 H. efh 1 / 2 of.

[0033] The radial stabilizer 6 is provided with a first nozzle 61, and the second connecting support pipe 5 is connected to the first nozzle 61. The axial expansion angle θ of the radial stabilizer 6 is... rfh The angle is 10~30° to form a suitably shaped recirculation zone and control the blockage ratio. The radial stabilizer 6 is shaped like an arc-shaped trapezoid with an expansion angle, and the center of its axis is located on the afterburner axis. The height H of the radial stabilizer 6 is... ifh It needs to cover most of the radial height of the internal flow.

[0034] The central circumferential stabilizer 7 is provided with a second nozzle 71, and the first support tube 4 is connected to the second nozzle 71. The expansion angle of the second nozzle 71 is θ. ffh The axial expansion angle θ of the central circumferential stabilizer 7 is 30~60°, which is beneficial to the radial distribution of ignition fuel. Directly introducing hydrogen into the stabilizer creates a standby fuel distribution and injects it directly into the pre-stagnant point of the recirculation zone, avoiding premature diffusion of ignition fuel and ensuring ignition reliability. cfh The angle is 10~30° to form a suitable recirculation zone and control the blockage ratio. The central circumferential stabilizer 7 is an arc-shaped trapezoid with an expansion angle to organize stable and efficient combustion and flame connection of the circumferential mixing flow.

[0035] The outer duct radial stabilizer 8 is provided with a third nozzle 81, and the second connecting support pipe 5 is connected to the third nozzle 81. The axial expansion angle θ of the outer duct radial stabilizer 8 is... efh The angle is 10~30° to form a suitably shaped recirculation zone and control the blockage ratio. The outer bypass radial stabilizer 8 is used to organize stable and efficient combustion of the mixture flow in the outer bypass direction; its shape is an arc-shaped trapezoid with an expansion angle. The height H of the outer bypass radial stabilizer 8 is... efh It needs to cover most of the radial height of the incoming flow from the duct. The radial expansion angle θ of the duct radial stabilizer is 8. efh Inclination angle θ with respect to the fuel main ft Similarly, they serve a radial guiding function. Two adjacent outer radial stabilizers 8 form a central circumferential stabilizer with an included angle θ. cifh The angle is set to 10~20° to ensure a suitable blockage rate, thereby achieving stable combustion of fuel while reducing total pressure loss.

[0036] Connecting rod 9 is a solid component, serving as a rigid connection and support structure between the first fuel main 1, the second fuel main 2, and the third fuel main 3, with a diameter of 3-10mm. The number of fuel main connecting rods 9 can be selected according to requirements, such as 4-12, and can be evenly welded to the upper, middle, and lower positions of the first fuel main 1, the second fuel main 2, and the third fuel main 3 as needed. Ultimately, only one suspension structure is required for the three fuel mains.

Claims

1. A hydrogen supply structure for an afterburner, characterized in that: It includes a fuel manifold assembly and a stabilizer, wherein the fuel manifold assembly is connected to the stabilizer via a first connecting support pipe (4) and a second connecting support pipe (5); The fuel manifold assembly includes a first fuel manifold (1), a second fuel manifold (2), and a third fuel manifold (3). The second fuel manifold (2) is disposed between the first fuel manifold (1) and the third fuel manifold (3). The third fuel manifold (3) is disposed between the second fuel manifold (2) and the stabilizer. The first fuel manifold (1), the second fuel manifold (2), and the third fuel manifold (3) are connected and fastened together by a connecting rod (9).

2. The hydrogen supply structure for an afterburner as described in claim 1, characterized in that: Below the third fuel main pipe (3), a first connecting pipe (31) and a second connecting pipe (32) are provided. The first connecting pipe (31) and the second connecting pipe (32) are respectively connected to the bottom of the third fuel main pipe (3). The first connecting pipe (31) is connected to the stabilizer through the first connecting support pipe (4) and the second connecting support pipe (5). The second connecting pipe (32) is connected to the stabilizer through the first connecting support pipe (4) and the second connecting support pipe (5).

3. The hydrogen supply structure for an afterburner as described in claim 1, characterized in that: The fuel manifold spacing D formed by the first fuel manifold (1), the second fuel manifold (2), and the third fuel manifold (3) ft It needs to be greater than 1.5 times the maximum diameter of the first fuel manifold (1), the second fuel manifold (2), and the third fuel manifold (3), and the distance D from the third fuel manifold (3) to the stabilizer. tfh fuel mains spacing D ft More than 1.5 times that.

4. The hydrogen supply structure for an afterburner as described in claim 1, characterized in that: A third connecting pipe (11) and a fourth connecting pipe (12) are provided on the first fuel main pipe (1). The length of the third connecting pipe (11) is greater than the length of the fourth connecting pipe (12). Fuel holes (13) are provided on the third connecting pipe (11) and the fourth connecting pipe (12). The third connecting pipe (11) and the fourth connecting pipe (12) are respectively connected to the bottom of the first fuel main pipe (1). The spacing of the fuel holes (13) on the third connecting pipe (11) is greater than the spacing of the fuel holes (13) on the fourth connecting pipe (12).

5. The hydrogen supply structure for an afterburner as described in claim 1, characterized in that: The height H of the first fuel manifold (1) ft It needs to be greater than 2 / 3 of the stabilizer's maximum height, which is H. efh +H ifh .

6. The hydrogen supply structure for an afterburner as described in claim 1, characterized in that: The stabilizer includes an inner radial stabilizer (6), a central circumferential stabilizer (7), and an outer radial stabilizer (8). The inner radial stabilizer (6) is internally connected to the central circumferential stabilizer (7) and the outer radial stabilizer (8). One end of the central circumferential stabilizer (7) is connected to the inner radial stabilizer (6), and the other end is connected to the outer radial stabilizer (8). The inner radial stabilizer (6) is connected to the fuel manifold assembly through a second connecting support pipe (5). The central circumferential stabilizer (7) is connected to the fuel manifold assembly through a first support pipe (4). The outer radial stabilizer (8) is connected to the fuel manifold assembly through a second connecting support pipe (5).

7. The hydrogen supply structure for an afterburner as described in claim 6, characterized in that: The inner radial stabilizer (6) is provided with a first nozzle (61), and the second connecting support pipe (5) is connected to the first nozzle (61). The axial expansion angle θ of the inner radial stabilizer (6) is... rfh The range is 10~30°.

8. The hydrogen supply structure for an afterburner as described in claim 6, characterized in that: The central circumferential stabilizer (7) is provided with a second nozzle (71), and the first support tube (4) is connected to the second nozzle (71). The axial expansion angle θ of the central circumferential stabilizer (7) is... cfh The range is 10~30°.

9. The hydrogen supply structure for an afterburner as described in claim 6, characterized in that: The outer radial stabilizer (8) is provided with a third nozzle (81), and the second connecting support pipe (5) is connected to the third nozzle (81).

10. The hydrogen supply structure for an afterburner as described in claim 6, characterized in that: The axial expansion angle θ of the outer circumferential radial stabilizer (8) efh The range is 10~30°.

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