Supersonic combustion chamber air resonance ignition device and ignition method

Abstract

The invention discloses a supersonic combustion chamber air resonance ignition device and ignition method, and belongs to the technical field of combustion chamber ignition. The supersonic combustion chamber air resonance ignition device comprises a resonance structure and a blocking structure, the blocking structure and the resonance structure are both arranged in an expansion section of a combustion chamber, and the blocking structure is located at the front end of the resonance structure; the resonant structure comprises wedge-shaped supporting plates which are symmetrically arranged, a contraction spraying pipe is arranged between the front ends of the supporting plates, the plugging structure is located at the air inlet end of the contraction spraying pipe and used for closing or opening the contraction spraying pipe, a resonant plate is arranged between the rear ends of the supporting plates, a resonant pipe is arranged in the middle of the resonant plate, and a drainage groove is formed between the resonant plate and the supporting plates; an oil injection structure for injecting fuel oil into the expansion section is arranged on the supporting plate, and a gas inlet structure for providing fuel gas for ignition is arranged at the tail end of the resonance plate. According to the air resonance ignition device and method for the supersonic combustion chamber, the stable combustion supporting plate and the resonance plate are arranged in the combustor, repeated ignition in a non-electric ignition mode is achieved through the pneumatic resonance heat effect, and the combustion stability of the combustion chamber is improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of combustion chamber ignition, in particular to an air resonance ignition device and method for a supersonic combustion chamber. BACKGROUND

[0002] The scramjet engine is the best choice for achieving hypersonic flight in the atmosphere at present, and it has extremely important value in space-air transportation, improving air defense power in the near space middle section, etc. It is the focus of research and competition in aviation and aerospace of various countries at present. Among them, the combustion chamber is the core engine of the scramjet engine. The flow velocity of the core flow in the supersonic combustion chamber is usually more than 1000m / s, and the residence time of the fuel is only milliseconds. The widely used liquid fuel needs to undergo breaking, atomization and mixing before ignition in the combustion chamber, and the ignition delay time of the liquid fuel is significantly longer than that of the gas fuel, which brings great challenges to the ignition and stable combustion of the supersonic combustion chamber.

[0003] The stable combustion method in the supersonic combustion chamber is divided into invasive and non-invasive two kinds. The non-invasive stable combustion method relies on the low-speed backflow area generated by the wall cavity or backward step; the invasive stable combustion method usually uses a strut, which has the effect of injection and stable combustion. Compared with the non-invasive stable combustion method, the use of strut for stable combustion can effectively improve the fuel injection penetration depth and reduce the combustion chamber wall heat flux.

[0004] The currently developed ignition technologies include spark ignition, plasma torch ignition, air throttling ignition and the like. The spark ignition has insufficient energy, and is often used in gas fuel scramjet engines and in combination with self-ignition mode. The pilot gas ignition and hot jet are effective ignition modes in actual use, and need to be equipped with an additional fuel supply system. The air throttling ignition can effectively promote ignition and the throttling system is simple, but needs to work with an additional igniter. The plasma torch ignition can continuously inject high-temperature gas into the combustion chamber, and the ignition energy is significantly enhanced, but strong electromagnetic interference is generated. SUMMARY

[0005] The purpose of the present application is to provide an air resonance ignition device and method for a supersonic combustion chamber, which sets a stable combustion strut and a resonance plate in the combustor, uses the aerodynamic resonance heat effect to realize repeated ignition of the non-electric ignition mode, and improves the stability of the combustion chamber combustion.

[0006] To achieve the above object, the application provides an air resonance ignition device for a supersonic combustion chamber, which comprises a resonance structure and a blocking structure, the blocking structure and the resonance structure are arranged in an expansion section of the combustion chamber, and the blocking structure is located at the front end of the resonance structure; the resonance structure comprises symmetrically arranged wedge-shaped support plates, a convergent nozzle is arranged between the front ends of the support plates, the blocking structure is located at the air inlet end of the convergent nozzle to close or open the convergent nozzle, a resonance plate is arranged between the rear ends of the support plates, a resonance tube is arranged in the middle of the resonance plate, and a flow leakage groove is arranged between the resonance plate and the support plates; an oil injection structure for injecting fuel into the expansion section is arranged on the support plates, and an air inlet structure for providing fuel gas for ignition is arranged at the tail end of the resonance plate.

[0007] Preferably, the convergent nozzle comprises an outer convex circular arc segment, an inner convex circular arc segment and a horizontal segment which are sequentially arranged along the airflow direction and are smoothly connected, the horizontal segment is located in the tangent direction of the inner convex circular arc segment, and the tail end of the convergent nozzle is connected to the front end of the flow leakage groove through a stepped surface.

[0008] Preferably, the resonance tube is coaxially arranged with the convergent nozzle, the resonance tube is an axisymmetric structure, the resonance tube comprises a tapered convergent segment gradually converging inward in the front part along the airflow direction and a rectangular segment in the rear part, and the ratio of the air inlet width of the resonance tube to the air outlet width of the convergent nozzle is 1.5:1.

[0009] Preferably, the tail end of the resonance plate gradually converges inward against the airflow direction, and the tail end of the resonance tube protrudes from the resonance plate.

[0010] Preferably, the oil injection structure comprises a fuel channel, the fuel channel is vertically arranged in the interior of the support plate, and a plurality of oil injection holes in communication with the fuel channel are arranged on the side wall of the support plate close to the expansion section.

[0011] Preferably, the air inlet structure comprises an oxygen channel and a fuel gas channel, a plurality of oxygen gas injection holes in communication with the oxygen channel are arranged at the tail end of the resonance plate, a plurality of fuel gas injection holes in communication with the fuel gas channel are arranged at the tail end of the resonance plate, the oxygen gas injection holes and the fuel gas injection holes are symmetrically arranged on both sides of the resonance tube, and the oxygen gas injection holes are located outside the fuel gas injection holes.

[0012] Preferably, the blocking structure comprises a wedge-shaped blocking block, a sliding hole through which the blocking block passes is arranged on the mounting plate, the blocking block is in sealing sliding connection with the sliding hole, a hydraulic cylinder for driving the blocking block to insert into or move out of the expansion section is arranged on the expansion section, and the outer side surface of the blocking block is flush with the outer side surface of the support plate.

[0013] Preferably, the included angle between the outer side surfaces of the two support plates is not greater than the included angle of the inner side surface of the expansion section, and the expansion ratio of the expansion section is 1.5.

[0014] Preferably, the air inlet end of the expansion section is connected with the isolation section of the supersonic ramjet engine, and the air outlet end of the expansion section is connected with the equal-area section of the combustion chamber; the expansion section is provided with a mounting hole for placing a mounting plate, and the mounting plate is in sealing and fixed connection with the expansion section.

[0015] The ignition method based on the air-resonance ignition device of the supersonic combustion chamber comprises the following steps:

[0016] S1, when the aircraft reaches the ignition working condition, the hydraulic cylinder contracts to drive the blocking block to slide out of the expansion section along the sliding hole, and the contraction nozzle is opened;

[0017] S2, the contraction nozzle takes air from the main flow of the expansion section, pressurizes and decelerates the supersonic airflow in the main flow into an under-expanded sonic airflow, part of the under-expanded sonic airflow enters the resonance tube, vibrates in the resonance tube, generates a pneumatic resonance heat effect, and forms a highest temperature distribution area at the tail of the resonance tube; the other part of the under-expanded sonic airflow enters the main flow of the expansion section through the leakage groove;

[0018] S3, after the temperature at the tail of the resonance tube reaches the ignition temperature, the fuel gas channel and the oxygen channel are opened, the ethylene fuel gas and the oxygen enter the tail of the resonance plate through the fuel gas injection hole and the oxygen injection hole respectively, form mixed gas in the tail of the resonance tube, and the mixed gas is ignited by the high-temperature tail of the resonance tube to form a standby ethylene flame in the backflow area of the branch plate tail;

[0019] S4, the fuel oil channel is opened, the fuel oil enters the expansion section of the combustion chamber through the fuel injection hole, the fuel oil is broken, atomized and mixed by the supersonic airflow to form a fuel oil-air mixture, which is ignited by the ethylene standby flame in the branch plate tail to obtain a fuel oil-ethylene mixed standby flame;

[0020] S5, the fuel gas channel is closed, and then the oxygen channel is closed, to form a stable fuel oil standby flame in the branch plate tail;

[0021] S6, the hydraulic cylinder is elongated, the hydraulic cylinder drives the blocking block to insert into the expansion section to block the contraction nozzle, and the ignition is completed.

[0022] The advantages and positive effects of the air-resonance ignition device and ignition method of the supersonic combustion chamber are as follows:

[0023] 1. The branch plate is arranged in the expansion section, the under-expanded sonic airflow is formed through the branch plate, and a large-scale backflow area is formed behind the branch plate, which is beneficial to improve the stability of the combustion chamber combustion.

[0024] 2. The high-temperature area is formed at the tail end of the resonance tube through the pneumatic resonance heat effect of the resonance tube, the mixed gas of fuel and oxygen is ignited by the high-temperature resonance tube, and the purpose of non-electric ignition is achieved.

[0025] The technical solutions of the present application are described in further detail below with reference to the accompanying drawings and examples. BRIEF DESCRIPTION OF DRAWINGS

[0026] Figure 1 is a perspective view of the structure of an embodiment of the present application;

[0027] Figure 2 is a front view of the structure of an embodiment of the present application;

[0028] Figure 3 is a top view of the structure of an embodiment of the present application;

[0029] Figure 4 is a perspective view of the resonant structure of an embodiment of the present application;

[0030] Figure 5 is a sectional view of the resonant structure of an embodiment of the present application;

[0031] Figure 6 is an enlarged view of Figure 5 A;

[0032] Figure 7 is a perspective view of the tail end structure of a resonant structure of an embodiment of the present application;

[0033] Figure 8 is a perspective view of the plugging structure of an embodiment of the present application;

[0034] Figure 9 is a perspective view of the mounting plate structure of an embodiment of the present application;

[0035] Figure 10 is a perspective view of the ignition device in the mounted state of an embodiment of the present application;

[0036] Figure 11 is a sectional view of the ignition device in the mounted state of an embodiment of the present application;

[0037] Figure 12 is a perspective view of the expansion section of an embodiment of the present application;

[0038] Figure 13 is a numerical simulation result of a resonant ignition device of an embodiment of the present application.

[0039] REFERENCE NUMERALS

[0040] 1, plugging block; 2, support plate; 3, resonant plate; 4, mounting plate; 5, hydraulic cylinder; 6, oil injection hole; 7, fuel passage; 8, converging nozzle; 9, resonant tube; 10, flow relief groove; 11, oxygen passage; 12, fuel gas passage; 13, oxygen injection hole; 14, fuel gas injection hole; 15, sliding hole; 16, expansion section; 17, isolation section; 18, equal-area section; 19, mounting hole. DETAILED DESCRIPTION

[0041] In the description of the present application, it should be noted that the terms "upper", "lower", "inner", "outer" and the like indicate the orientation or positional relationship shown in the drawings, or the orientation or positional relationship in which the product of the present application is usually placed, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the device or element referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as a limitation on the present application. In the description of the present application, it should be noted that, unless otherwise specified and limited, the terms "provided", "mounted", "connected" should be understood broadly, for example, can be fixedly connected, can be detachably connected, or integrally connected; can be mechanically connected, or electrically connected; can be directly connected, or indirectly connected through an intermediate medium, or can be connected internally between two elements. For those skilled in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances.

[0042] In the present application, unless otherwise defined, all technical and scientific terms used herein have the same meaning as understood by those skilled in the art to which the present application belongs. If there is any inconsistency, the meaning described in the specification or derived from the content described in the specification shall prevail. In addition, the terms used herein are only for the purpose of describing the embodiments of the present application and are not intended to limit the present application.

[0043] The embodiments of the present application will be described in detail below with reference to the accompanying drawings.

[0044] As shown in Figure 1 , Figure 2 , Figure 3 An ultrasonic combustion chamber air resonance ignition device, as shown in the drawings, comprises a resonance structure and a blocking structure, and the blocking structure and the resonance structure are both arranged in the expansion section 16 of the combustion chamber. The blocking structure is located at the front end of the resonance structure and is used to close or open the resonance structure.

[0045] As shown in Figure 4 , Figure 5 The resonance structure comprises symmetrically arranged wedge-shaped support plates 2, the top ends of the support plates 2 are in close contact with the top end of the expansion section 16, so that the main flow gas of the expansion section 16 passes through the two sides of the support plates 2. A convergent nozzle 8 is arranged between the front ends of the support plates 2, and the blocking structure is located at the gas inlet end of the convergent nozzle 8 for closing or opening the convergent nozzle 8. The convergent nozzle 8 comprises an outer convex circular arc segment, an inner convex circular arc segment and a horizontal segment which are arranged in sequence along the airflow direction and are smoothly transitioned, and the horizontal segment is located in the tangent direction of the inner convex circular arc segment. The smoothly transitioned convergent nozzle 8 achieves the purpose of wave elimination, reducing the influence of the irregular wave on the supersonic airflow. The main flow gas of supersonic speed is pressurized and decelerated after passing through the convergent nozzle 8 to form an under-expanded sonic airflow.

[0046] A resonant plate 3 is arranged between the rear ends of the support plates 2, and the resonant plate 3 is fixed to the mounting plate 4. The resonant plate 3 is provided with a resonant tube 9 in the middle part, and the resonant tube 9 is coaxially arranged with the convergent nozzle 8 and has an axisymmetric structure. The resonant tube 9 includes a tapered convergent section gradually converging inward along the airflow direction in the front part and a rectangular section in the rear part. The ratio of the width of the air inlet of the resonant tube 9 to the width of the air outlet of the convergent nozzle 8 is 1.5:1, so that the under-expanded sonic airflow can fully enter the resonant tube 9. The tail end of the resonant tube 9 is a blind end. The under-expanded sonic airflow bounces back and forth in the resonant tube 9, and the resonant thermal effect is generated. The highest temperature is reached at the tail end of the resonant tube 9, and the ignition is performed by the high temperature at the tail end of the resonant tube 9, without the need for electric ignition.

[0047] The tail end of the resonant plate 3 gradually converges inward against the airflow direction, and a large-size low-speed backflow area is formed downstream of the support plates 2 and the resonant plate 3 to realize oxygen-free auxiliary stable combustion after ignition.

[0048] The resonant plate 3 is provided with a flow discharge groove 10 between the support plates 2, and the flow discharge groove 10 is used to discharge the under-expanded sonic airflow into the main flow. The tail end of the convergent nozzle 8 is connected to the front end of the flow discharge groove 10 through a stepped surface. The flow discharge groove has a gradually expanding structure, which can accelerate the supersonic airflow, discharge the gas to the tail end of the support plate, smoothly discharge the gas obtained in the main flow by the convergent nozzle, and ensure the continuous operation of the convergent nozzle and the resonant tube.

[0049] The support plate 2 is provided with an oil injection structure for injecting fuel into the expansion section 16. The oil injection structure includes a fuel channel 7 vertically arranged in the interior of the support plate 2. The fuel channel 7 is symmetrically arranged about the axis of the expansion section 16. The side wall of the support plate 2 close to the expansion section 16 is provided with a plurality of oil injection holes 6 in communication with the fuel channel 7, and the fuel is sent into the combustion chamber through the fuel channel 7 and the oil injection holes 6.

[0050] As shown in Figure 6 , Figure 7 , the tail end of the resonant plate 3 is provided with an air inlet structure for providing fuel gas for ignition. The air inlet structure includes an oxygen channel 11 and a fuel gas channel 12. The tail end of the resonant plate 3 is provided with a plurality of oxygen gas injection holes 13 in communication with the oxygen channel 11, and the tail end of the resonant plate 3 is provided with a plurality of fuel gas injection holes 14 in communication with the fuel gas channel 12. The oxygen gas injection holes 13 and the fuel gas injection holes 14 are symmetrically arranged on both sides of the resonant tube 9, and the oxygen gas injection holes 13 are located outside the fuel gas injection holes 14. Oxygen and fuel gas are injected into the tail end of the resonant plate 3 through the oxygen gas injection holes 13 and the fuel gas injection holes 14, and mixed gas is formed in the blind end of the resonant cavity. The mixed gas is ignited by the high temperature of the resonant cavity in a non-electric ignition manner.

[0051] As shown in Figure 8 ,Figure 9 As shown in the figure, the blocking structure includes a wedge-shaped blocking block 1, and a sliding hole 15 is arranged on the mounting plate 4 to allow the blocking block 1 to pass through, and the blocking block 1 is in sealing sliding connection with the sliding hole 15. A hydraulic cylinder 5 is arranged on the expansion section 16 to drive the blocking block 1 to insert into or move out of the expansion section 16, and the outer side surface of the blocking block 1 is flush with the outer side surface of the support plate 2. The blocking block 1 is inserted into or moved out of the expansion section 16 under the action of the hydraulic cylinder 5, so as to open or close the convergent nozzle 8, and realize the switching between the working and closing states of the resonant ignition device.

[0052] As shown in the figure, Figure 10 , Figure 11 , Figure 12 As shown in the figure, the outer side surface of the support plate 2 is a wedge surface, and the included angle between the outer side surfaces of the two support plates 2 is not greater than the included angle of the inner side surface of the expansion section 16, so that the flow area of the combustion chamber expansion section 16 is not less than the flow area of the isolation section 17 to suppress the non-starting trend of the combustion chamber. The outer surface of the resonant plate 3 is also a wedge surface, and the top end of the resonant plate 3 is closely connected with the top end of the expansion section 16. The flow area in the combustion chamber reaches the maximum value at the end of the expansion section 16, and the equal-area section 18 connected after the expansion section 16 can effectively accommodate the back pressure. The expansion ratio of the expansion section 16 is 1.5, the inlet end of the expansion section 16 is connected with the isolation section 17 of the supersonic ramjet engine, and the outlet end of the expansion section 16 is connected with the equal-area section 18 of the combustion chamber. The expansion section 16 is provided with a mounting hole 19 for placing the mounting plate 4, and the mounting plate 4 is in sealing and fixed connection with the expansion section 16 through a sealing ring and screws.

[0053] Based on the above-mentioned ignition method of the supersonic combustion chamber air resonance ignition device, the following steps are included:

[0054] S1, when the aircraft reaches the ignition working condition, the hydraulic cylinder 5 contracts to drive the blocking block 1 to slide out of the expansion section 16 along the sliding hole 15, the top end of the blocking block 1 is flush with the bottom surface of the expansion section, and the convergent nozzle 8 is opened.

[0055] S2, the convergent nozzle 8 takes air from the main flow of the expansion section 16, pressurizes and decelerates the supersonic flow in the main flow into an under-expanded sonic flow, part of the under-expanded sonic flow enters the resonant tube 9, vibrates in the resonant tube 9, generates a pneumatic resonance heat effect, and forms a highest temperature distribution area at the tail of the resonant tube 9. Another part of the under-expanded sonic flow enters the main flow of the expansion section through the leakage groove 10.

[0056] S3, after the tail temperature of the resonant tube 9 reaches the ignition temperature after working for a period of time, the fuel gas passage 12 and the oxygen gas passage 11 are opened, the ethylene fuel gas and the oxygen gas enter the tail of the resonant plate 3 through the fuel gas injection hole 14 and the oxygen gas injection hole 13 respectively, form mixed gas in the tail of the resonant tube 9, and the mixed gas is ignited by the high-temperature tail of the resonant tube 9 to form a standing ethylene flame in the large-scale backflow area at the tail of the support plate 2.

[0057] S4, after the duty ethylene flame is established, the fuel oil passage 7 is opened, the fuel oil enters the expansion section 16 of the combustion chamber through the fuel injection hole 6, the fuel oil is broken, atomized and mixed by the supersonic airflow to form a fuel oil-air mixture which is ignited by the ethylene duty flame at the tail of the branch plate 2 to obtain a fuel oil-ethylene mixed duty flame.

[0058] S5, after the fuel oil-ethylene mixed duty flame is established, the fuel gas passage 12 is closed, the oxygen passage 11 is closed after 2 seconds, and a stable fuel oil duty flame is formed at the tail of the branch plate 2.

[0059] S6, the hydraulic cylinder 5 is elongated, the hydraulic cylinder 5 drives the blocking block 1 to insert into the expansion section 16 to block the convergent nozzle 8, avoid the resonant plate 3 from being ablated in a high temperature state for a long time, reduce the total pressure loss caused by the convergent nozzle 8, stop the ignition device from working, and complete the ignition.

[0060] If the one-time ignition is not successful or the engine has a restart requirement, the above steps are repeated for repeated ignition.

[0061] In order to more clearly illustrate the technical effects of the present application, numerical simulation is performed on the resonant ignition device, and the results are shown in Figure 13 As can be seen from the figure, the resonant ignition device resonates the air with a main stream static temperature of 740K to a static temperature of 2100K, and the highest temperature position of the ignition device is the blind end of the resonant pipe. The ethylene-oxygen mixture is injected into the blind end of the resonant pipe to ignite and form a central duty flame to ignite other fuels injected by the branch plate wedge surface, and the ignition is completed.

[0062] Therefore, by using the supersonic combustion chamber air resonant ignition device and the ignition method, the stable combustion branch plate and the resonant plate are arranged in the combustor, the aerodynamic resonant heat effect is used to realize the repeated ignition of the non-electric ignition mode, and the stability of the combustion chamber combustion is improved.

[0063] Finally, it should be noted that: the above examples are only used to illustrate the technical solutions of the present application and not to limit them, although the present application has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solutions of the present application can still be modified or replaced by equivalents, and these modifications or equivalent replacements cannot make the modified technical solutions deviate from the spirit and scope of the technical solutions of the present application.

Claims

1. An air resonance ignition device for a supersonic combustion chamber, characterized by: It includes a resonance structure and a blocking structure, both of which are arranged in the expansion section of the combustion chamber, and the blocking structure is located at the front end of the resonance structure; the resonance structure includes symmetrically arranged wedge-shaped support plates, a convergence nozzle is arranged between the front ends of the support plates, the blocking structure is located at the air inlet end of the convergence nozzle and is used to close or open the convergence nozzle, a resonance plate is arranged between the rear ends of the support plates, a resonance tube is arranged in the middle of the resonance plate, and a discharge groove is arranged between the resonance plate and the support plate; an injection structure for injecting fuel into the expansion section is arranged on the support plate, and an air intake structure for providing gas for ignition is arranged at the tail end of the resonance plate.

2. The supersonic combustion chamber air resonance ignition device according to claim 1, characterized in that: The convergent nozzle includes an outward convex arc section, an inward convex arc section and a horizontal section which are arranged in sequence along the airflow direction and smoothly transitioned. The horizontal section is located in the tangent direction of the inward convex arc section. The tail end of the convergent nozzle is connected to the front end of the discharge groove by a step surface.

3. The supersonic combustion chamber air resonance ignition device according to claim 1, characterized in that: The resonance tube is coaxially arranged with the convergent nozzle. The resonance tube has an axisymmetric structure. The resonance tube includes a conical convergent section at the front that gradually converges inward along the airflow direction and a rectangular section at the rear. The ratio of the width of the air inlet of the resonance tube to the width of the air outlet of the convergent nozzle is 1.5:

1.

4. The supersonic combustion chamber air resonance ignition device according to claim 1, characterized in that: The tail end of the resonance plate gradually shrinks inwards against the direction of the airflow, and the tail blind end of the resonance tube protrudes from the resonance plate.

5. The supersonic combustion chamber air resonance ignition device according to claim 1, characterized in that: The fuel injection structure includes a fuel channel, which is vertically arranged inside the support plate. A plurality of fuel injection holes connected to the fuel channel are arranged on the side wall of the support plate close to the expansion section.

6. The supersonic combustion chamber air resonance ignition device according to claim 1, characterized in that: The air intake structure includes an oxygen channel and a gas channel. The tail end of the resonance plate is provided with a plurality of oxygen jet holes connected to the oxygen channel. The tail end of the resonance plate is provided with a plurality of gas jet holes connected to the gas channel. The oxygen jet holes and the gas jet holes are symmetrically arranged on both sides of the resonance tube, and the oxygen jet holes are located outside the gas jet holes.

7. The supersonic combustion chamber air resonance ignition device according to claim 1, characterized in that: The blocking structure includes a wedge-shaped blocking block, a sliding hole for the blocking block to pass through is provided on the mounting plate, the blocking block is sealingly and slidingly connected to the sliding hole, a hydraulic cylinder is provided on the expansion section to drive the blocking block to insert or move out of the expansion section, and the outer side surface of the blocking block is flush with the outer side surface of the support plate.

8. The supersonic combustion chamber air resonance ignition device according to claim 1, characterized in that: The included angle between the outer side surfaces of the two support plates is no greater than the included angle between the inner side surfaces of the expansion section, and the expansion ratio of the expansion section is 1.

5.

9. The air resonance ignition device for a supersonic combustion chamber according to claim 1, characterized in that: The air inlet end of the expansion section is connected to the isolation section of the supersonic ramjet engine, and the air outlet end of the expansion section is connected to the equal-area section of the combustion chamber; a mounting hole for placing a mounting plate is provided on the expansion section, and the mounting plate is sealed and fixedly connected to the expansion section.

10. An ignition method for an air resonance ignition device for a supersonic combustion chamber according to any one of claims 1 to 9, characterized in that: The following steps are involved: S1: When the aircraft reaches the ignition condition, the hydraulic cylinder contracts and drives the blocking block to slide out of the expansion section along the sliding hole, and the nozzle is retracted to open; S2: The converging nozzle draws air from the mainstream of the expanding section, pressurizing and decelerating the supersonic airflow in the mainstream into an underexpanded sonic airflow. Part of the underexpanded sonic airflow enters the resonance tube, where it reflects and vibrates, generating aerodynamic resonance thermal effects and forming the highest temperature distribution area at the tail of the resonance tube; the other part of the underexpanded sonic airflow enters the mainstream of the expanding section through the discharge groove; S3. After the temperature at the tail of the resonance tube reaches the ignition temperature, the gas channel and the oxygen channel are opened, and the ethylene gas and oxygen enter the tail of the resonance plate through the gas jet hole and the oxygen jet hole respectively, and mix to form a mixed gas at the tail of the resonance tube. The mixed gas is ignited by the high-temperature tail of the resonance tube and forms an ethylene flame in the recirculation area at the tail of the support plate; S4. The fuel passage is opened, and the fuel enters the expansion section of the combustion chamber through the fuel injection hole. The fuel is broken, atomized, and mixed by the supersonic airflow to form a fuel-air mixture, which is ignited by the ethylene service flame at the tail of the support plate to obtain a fuel-ethylene mixed service flame. S5. Close the gas channel, then close the oxygen channel, and form a stable fuel duty flame at the rear of the support plate; S6. The hydraulic cylinder extends, and the hydraulic cylinder drives the blocking block to insert into the expansion section, blocking the contraction nozzle and completing ignition.

Images