A large-size ramjet combustion chamber

Abstract

The present application belongs to the field of combustion chamber design, and is a large-sized ramjet combustion chamber, including an outer wall and an organized combustion system, the organized combustion system is arranged on the inner side of the outer wall, and the organized combustion system includes a pre-combustion chamber, a fuel injection rod and a stabilizer; when working, the high-temperature and high-pressure gas and fuel formed by the air bleed pipe from the fan interstage flow through the oil-gas mixing duct into the pre-combustion chamber head, and the oil-gas mixture is sprayed into the pre-combustion chamber through the swirl nozzle, and ignited by the ignition nozzle to generate a stable flame. Then, the flame is ejected through the flame nozzle in the recirculation zone formed by the stabilizer to ignite the oil-gas mixture behind the annular stabilizer, so as to realize the reliable ignition of the ramjet combustion chamber and the full-state combustion of the ramjet combustion chamber, increase the gas temperature and exhaust speed, and thus improve the thrust of the engine. The fan interstage air bleed can solve the problem of fan terminal blockage, improve the flow capacity of the fan at low speed, and the air flow speed is low, and the ignition success rate is high.

Description

Technical Field

[0001] The present application belongs to the field of combustion chamber design, and in particular to a large-sized ramjet combustion chamber. Background Art

[0002] For traditional parallel turboramjet combination engines, the mode conversion is performed when the engine inlet Mach number is 2.5-3.0, and the working state of the turbine engine is transitioned to the working state of the ramjet engine. In recent years, in order to reduce the aerodynamic drag generated by the parallel engine and give full play to the advantages of the overall propulsion system, it is hoped that the mode conversion will start when the engine inlet Mach number is about 2.5.

[0003] Traditional ramjet combustion chambers rely on high-energy ignition nozzles for ignition, and the nozzle ignition energy is low. It is difficult to start ramjet combustion chambers under harsh conditions. Further research is needed on advanced ignition methods suitable for ramjet combustion chambers under high Mach number conditions. By improving the ignition method, on the one hand, it is ensured that the ramjet combustion chamber can be reliably connected and the combustion is stable. On the other hand, it can ensure that the ramjet engine can be successfully started during the mode conversion, and the mode conversion between different types of engines can be successfully completed.

[0004] The existing ramjet combustion chamber uses a stabilizer to form a recirculation zone. After the fuel is injected into the recirculation zone, the combustion is organized after successful ignition through the ignition nozzle. Especially when the engine inlet Mach number is about 2.5 and the mode conversion is performed, the ramjet combustion chamber inlet air flow velocity is high, and the traditional nozzle ignition success rate is low, which can easily cause the engine mode conversion failure. Summary of the invention

[0005] The purpose of the present application is to provide a large-sized ramjet combustion chamber to solve or alleviate the problem of low success rate of electric nozzle ignition in the background technology.

[0006] The technical solution of the present application is: a large-sized ramjet combustion chamber, a large-sized ramjet combustion chamber, arranged in a ramjet engine, comprising an outer wall and an organized combustion system, the organized combustion system being arranged on the inner side of the outer wall, the organized combustion system comprising a pre-combustion chamber, a fuel injection rod and a stabilizer, the fuel injection rod being arranged at the front end of the pre-combustion chamber, the stabilizer being located at the rear end of the fuel injection rod, the pre-combustion chamber being a non-integral ring structure and the pre-combustion chamber being arranged on one side of a high-temperature internal passage of the engine, an ignition nozzle inserted into the pre-combustion chamber being arranged between the middle part of the pre-combustion chamber and the outer wall, a support plate being arranged between the head of the pre-combustion chamber and the outer wall, an air duct being arranged in the support plate, one end of the air duct being connected to the high-temperature and high-pressure gas introduced from the fan stage, and the other end being connected to the interior of the pre-combustion chamber.

[0007] Preferably, the stabilizer includes an inner radial stabilizer, an outer radial stabilizer, an inner ring annular stabilizer and an outer ring annular stabilizer; a flame nozzle is provided at the end of the pre-combustion chamber, the outlet direction of the flame nozzle is toward the inner ring annular stabilizer, an opening is provided on the outer radial stabilizer, and the flame nozzle is arranged at the opening; the outer ring annular stabilizer is connected to the outer side of the outer radial stabilizer, the outer radial stabilizer is arranged on the outer side of the inner ring annular stabilizer, and the inner ring annular stabilizer is arranged on the outer side of the inner radial stabilizer; the cross-sections of the inner ring annular stabilizer and the outer ring annular stabilizer are both triangular structures and the ends of the inner ring annular stabilizer and the outer ring annular stabilizer are arranged along the radial direction of the engine, and the inner radial stabilizer and the outer radial stabilizer are both inclined.

[0008] Preferably, the inner radial stabilizers and the outer radial stabilizers are provided in multiple groups and are evenly arranged along the circumference of the aircraft engine, and a tie rod is connected between the outer ring stabilizer and the outer wall.

[0009] Preferably, the cross-sections of the head and tail of the pre-combustion chamber are both triangular, and the tip of the head of the pre-combustion chamber faces the front end of the engine, and the tip of the tail of the pre-combustion chamber faces the rear end of the engine.

[0010] Preferably, the pre-combustion chamber is of integrated design and is formed by 3D printing.

[0011] Preferably, a cooling air duct is further provided in the support plate, one end of the cooling air duct is connected to the outer cooling channel of the ramjet engine, and the other end of the cooling air duct is connected to the interior of the pre-combustion chamber.

[0012] Preferably, a pressure diffuser and deceleration section is provided on the outer wall, the pressure diffuser and deceleration section adopts a constant pressure gradient shape, and the equivalent expansion angle of the pressure diffuser and deceleration section is 12 to 18 degrees.

[0013] Preferably, an anti-vibration and heat-insulating screen is provided on the inner side of the outer wall, the anti-vibration and heat-insulating screen is arranged at the rear end of the stabilizer, and cooling holes are opened on the anti-vibration and heat-insulating screen.

[0014] Preferably, the bleed air duct is capable of introducing bleed air from an external fan of the turbine engine.

[0015] The present invention discloses a large-sized ramjet combustion chamber, including an outer wall and a combustion organization system, wherein the combustion organization system is arranged on the inner side of the outer wall, and the combustion organization system includes a pre-combustion chamber, a fuel injection rod and a stabilizer; when working, the high-temperature and high-pressure gas introduced from the fan interstage by the air bleed pipe and the fuel oil form two flows of oil and gas through the oil-gas mixing conduit into the pre-combustion chamber head, and the oil-gas mixture is sprayed into the pre-combustion chamber through the swirl nozzle, and ignited by the ignition nozzle to generate a stable flame. Then, the flame is sprayed out through the flame nozzle in the recirculation zone formed by the stabilizer, and the oil-gas mixture behind the annular stabilizer is ignited, so as to realize the reliable ignition of the ramjet combustion chamber and the full-state combustion of the ramjet combustion chamber, increase the gas temperature and exhaust speed, and thus improve the thrust of the engine. The fan interstage air bleed can solve the problem of blockage of the last stage of the fan, improve the flow capacity of the fan at low speed, and the air flow speed is low, and the ignition success rate is high. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] In order to more clearly illustrate the technical solution provided by the present application, the following is a brief introduction to the accompanying drawings. Obviously, the accompanying drawings described below are only some embodiments of the present application.

[0017] Figure 1 This is a schematic diagram of the overall structure of this application;

[0018] Figure 2 This is a schematic diagram of the cooling of the pre-combustion chamber in the center of this application;

[0019] Figure 3 This is a schematic diagram of the circumferential layout of this application;

[0020] Figure 4 Organize the combustion system schematic for this application;

[0021] Figure 5 Schematic diagram of the stabilizer rod system for this application;

[0022] Figure 6 A schematic diagram of the cooling system for this application;

[0023] Figure 7 This is a schematic diagram of the cross section of the support plate of this application;

[0024] Figure 8 This is a schematic diagram of the combination of the ramjet engine and the turbine engine of the present application;

[0025] Fig. 9 This is a rear view of the ramjet and turbine engine combination of this application.

[0026] 1. Outer wall; 2. Anti-vibration and heat insulation screen; 3. Outer ring annular stabilizer; 4. Inner ring annular stabilizer; 5. Inner radial stabilizer; 6. Pre-combustion chamber; 7. Support plate; 8. Air bleed pipe; 9. Ignition nozzle; 10. Pull rod; 11. Cooling air duct; 12. Flame nozzle; 13. Fuel injection rod; 14. Outer radial stabilizer. DETAILED DESCRIPTION

[0027] In order to make the purpose, technical solutions and advantages of the implementation of this application clearer, the technical solutions in the embodiments of this application will be described in more detail below in conjunction with the drawings in the embodiments of this application.

[0028] A large-sized ramjet combustion chamber with a diameter of about 900mm to 1000mm is arranged in a ramjet engine. The front and rear ends of the ramjet combustion chamber are connected to the air inlet and the nozzle by bolts. The ramjet engine is provided with an inner cooling channel and a high-temperature inner channel. The outer cooling channel is used to circulate the outer cooling air, and the high-temperature inner channel is used to circulate the high-temperature and high-pressure gas.

[0029] like Figure 1-3 As shown, it includes an outer wall 1 and an organized combustion system, which is arranged on the inner side of the outer wall 1. The organized combustion system includes a precombustion chamber 6, a spray rod 13 and a stabilizer. The precombustion chamber 6 is a built-in precombustion chamber 6, a swirl nozzle is arranged at the head of the precombustion chamber 6, the spray rod 13 is arranged at the front end of the precombustion chamber 6, and the stabilizer is located at the rear end of the spray rod 13. The precombustion chamber 6 is a non-integral ring structure and the precombustion chamber 6 is arranged on one side of the high-temperature internal channel of the engine. An ignition nozzle 9 inserted into the precombustion chamber 6 is arranged between the middle of the precombustion chamber 6 and the outer wall 1, a support plate 7 is arranged between the head of the precombustion chamber 6 and the outer wall 1, and an air bleed pipe 8 and a wire of the ignition nozzle 9 are arranged in the support plate 7. One end of the air bleed pipe 8 is connected to the high-temperature and high-pressure gas induced from the fan stage, and the other end is connected to the inside of the precombustion chamber 6.

[0030] It should be noted that in the present application, the direction of the airflow is the front end of the ramjet engine, and the direction of the airflow is the rear end of the ramjet engine.

[0031] The present application adopts the pre-combustion chamber 6 for ramjet ignition. When the turbine engine is in a high Mach number state, the compression component is in a state of "gasping at the front and blocked at the back", and the insufficient flow capacity of the fan component will affect the engine thrust performance.

[0032] The high-temperature and high-pressure gas introduced from the fan interstage by the air duct 8 and the fuel form two flows of oil and gas through the oil-gas mixing conduit and enter the head of the pre-combustion chamber 6, and the oil-gas mixture is sprayed into the pre-combustion chamber 6 through the swirl nozzle, and ignited by the ignition nozzle 9 to generate a stable flame. Then, the flame is sprayed out through the flame nozzle 12 in the recirculation zone formed by the stabilizer, igniting the oil-gas mixture behind the annular stabilizer, realizing reliable ignition of the ramjet combustion chamber and full-state combustion of the ramjet combustion chamber, increasing the gas temperature and exhaust speed, and thus improving the thrust of the engine.

[0033] The problem of blockage in the last stage of the fan can be solved by introducing air between the fan stages, and the flow capacity of the fan at low speed can be improved. The air flow velocity is lower and the ignition success rate is higher, thereby effectively improving the success rate of engine mode conversion. Due to the reduction in air flow velocity, the "gasping at the front and blocked at the back" state of the compression components of the turbine engine can also be solved.

[0034] Combination Figure 4 Preferably, the stabilizer comprises an inner radial stabilizer 5, an outer radial stabilizer 14, an inner ring annular stabilizer 4 and an outer ring annular stabilizer 3, and different stabilizer positions form different reflow zones. A flame nozzle 12 is provided at the end of the pre-combustion chamber 6, and the outlet direction of the flame nozzle 12 faces the inner ring annular stabilizer 4. An opening is provided on the outer radial stabilizer 14, and the flame nozzle 12 is provided at the opening; the outer ring annular stabilizer 3 is connected to the outer side of the outer radial stabilizer 14, and the outer radial stabilizer 14 is provided on the outer side of the inner ring annular stabilizer 4, and the inner ring annular stabilizer 4 is provided on the outer side of the inner radial stabilizer 5; the cross sections of the inner ring annular stabilizer 4 and the outer ring annular stabilizer 3 are both triangular structures, and the ends of the inner ring annular stabilizer 4 and the outer ring annular stabilizer 3 are arranged along the radial direction of the engine, and the inner radial stabilizer 5 and the outer radial stabilizer 14 are both inclined.

[0035] After the pre-combustion chamber 6 is ignited, the injection rod 13 sprays fuel into the rear recirculation area of ​​the inner ring annular stabilizer 4 through the flame nozzle 12. Since the end of the inner ring annular stabilizer 4 is arranged along the radial direction of the engine, efficient ignition can be achieved, and then the flame is transmitted to the inner radial stabilizer 5 and the outer radial stabilizer 14 through the inner ring annular stabilizer 4 and combustion is organized. Since the inner radial stabilizer 5 and the outer radial stabilizer 14 are both inclined, they have efficient flame transmission performance, and finally transmitted to the outer ring annular stabilizer 3 through the outer radial stabilizer 14. Since the end of the outer ring annular stabilizer 3 is arranged along the radial direction of the engine, efficient combustion can be guaranteed. Through the mutual cooperation of the inner radial stabilizer 5, the outer radial stabilizer 14, the inner ring annular stabilizer 4 and the outer ring annular stabilizer 3, efficient flame transmission and stable combustion can be achieved.

[0036] Preferably, there are multiple groups of inner radial stabilizers 5 and outer radial stabilizers 14, which are evenly arranged along the circumference of the aircraft engine. Specifically, there are 6-8 inner radial stabilizers 5 and outer radial stabilizers 14, and the specific number can be determined according to the requirements of the ramjet combustion chamber blockage ratio. A tie rod 10 is connected between the outer ring stabilizer 3 and the outer wall 1. Figure 5 As shown, the outer ring stabilizer 3 is fixed to the outer wall 1 by tie rods 10, and the number of tie rods 10 is determined by the weight and load-bearing conditions of the stabilizer.

[0037] Preferably, the head and tail cross-sections of the pre-combustion chamber 6 are both triangular, and the tip of the head of the pre-combustion chamber 6 faces the front end of the engine, and the tip of the tail of the pre-combustion chamber 6 faces the rear end of the engine. This design ensures that the high-temperature and high-pressure gas in the high-temperature internal channel encounters less resistance when passing through the pre-combustion chamber 6, thereby realizing a low flow resistance design of the ramjet combustion chamber and ensuring efficient flow of the internal gas.

[0038] Preferably, the pre-combustion chamber 6 is of integrated design and is formed by 3D printing to reduce weight and simplify structure.

[0039] Preferably, a cooling air duct 11 is also provided in the support plate 7, one end of the cooling air duct 11 is connected to the outer cooling channel of the ramjet engine, and the other end is connected to the inside of the precombustion chamber 6. The cold air introduced by the cooling air duct 11 is used to cool the outer wall 1 of the precombustion chamber 6, ensuring that the precombustion chamber 6 is always in a relatively stable working state.

[0040] Preferably, a pressure diffuser and deceleration section is provided on the outer wall 1, and the pressure diffuser and deceleration section is connected to the cooling air duct 11 and the air duct 8. The pressure diffuser and deceleration section adopts an isopressure gradient shape, and the equivalent expansion angle of the pressure diffuser and deceleration section is 12 to 18 degrees, so as to realize the rectification and pressure diffusion of the outer wall 1, avoid the airflow diversion caused by the rapid pressure diffusion and speed reduction, reduce the airflow pressure diffusion loss, and realize the low flow resistance design of the ramjet combustion chamber.

[0041] Preferably, an anti-vibration heat insulation screen 2 is provided on the inner side of the outer wall 1, and the anti-vibration heat insulation screen 2 is provided at the rear end of the stabilizer. A cooling hole is provided on the anti-vibration heat insulation screen 2. The cooling system consists of two parts: a main channel A and a cooling channel B. Figure 6 As shown, the main channel A and channel B are separated by the anti-vibration heat insulation screen 2. The cooling air in the cooling channel B cools the outer wall 11, and the cavity of the main channel A and the cooling holes of the anti-vibration heat insulation screen 22 form a Helmholtz resonator, which plays a role in suppressing oscillating combustion.

[0042] like Figure 7 As shown, preferably, the number of the support plate 7 is one, and the support plate 7 is a streamlined structure to reduce the resistance to the high-temperature contained gas and improve the contained air flow efficiency.

[0043] Preferably, the ramjet engine of the present application is placed in parallel with the turbine engine, and air is introduced from the turbine engine outer fan to the pre-combustion chamber 6 through the bleed pipe 88 to participate in the ignition and combustion of the pre-combustion chamber 6. Figure 8 , 9 As shown, efficient air bleed is achieved.

[0044] The above is only a specific implementation of the present application, but the protection scope of the present application is not limited thereto. Any changes or substitutions that can be easily thought of by a person skilled in the art within the technical scope disclosed in the present application should be included in the protection scope of the present application. Therefore, the protection scope of the present application shall be based on the protection scope of the claims.

Claims

1. A large-sized ramjet combustion chamber, provided in a ramjet engine, characterized in that: The invention comprises an outer wall (1) and a combustion organization system, wherein the combustion organization system is arranged on the inner side of the outer wall (1), and comprises a pre-combustion chamber (6), a fuel injection rod (13) and a stabilizer, wherein the fuel injection rod (13) is arranged at the front end of the pre-combustion chamber (6), and the stabilizer is located at the rear end of the fuel injection rod (13). The pre-combustion chamber (6) is a non-integral ring structure and the pre-combustion chamber (6) is arranged on one side of a high-temperature internal passage of the engine. An ignition nozzle (9) inserted into the pre-combustion chamber (6) is arranged between the middle part of the pre-combustion chamber (6) and the outer wall (1). A support plate (7) is arranged between the head of the pre-combustion chamber (6) and the outer wall (1). An air duct (8) is arranged in the support plate (7). One end of the air duct (8) is connected to the high-temperature and high-pressure gas introduced from the fan stage, and the other end is connected to the inside of the pre-combustion chamber (6).

2. The large-size ramjet combustion chamber according to claim 1, characterized in that: The stabilizer comprises an inner radial stabilizer (5), an outer radial stabilizer (14), an inner ring annular stabilizer (4) and an outer ring annular stabilizer (3); a flame nozzle (12) is provided at the end of the pre-combustion chamber (6), the outlet direction of the flame nozzle (12) is toward the inner ring annular stabilizer (4), the outer radial stabilizer (14) is provided with an opening, and the flame nozzle (12) is arranged at the opening; the outer ring annular stabilizer (3) is connected to the outer side of the outer radial stabilizer (14), the outer radial stabilizer (14) is arranged on the outer side of the inner ring annular stabilizer (4), and the inner ring annular stabilizer (4) is arranged on the outer side of the inner radial stabilizer (5); the cross sections of the inner ring annular stabilizer (4) and the outer ring annular stabilizer (3) are both triangular structures, and the ends of the inner ring annular stabilizer (4) and the outer ring annular stabilizer (3) are arranged along the radial direction of the engine, and the inner radial stabilizer (5) and the outer radial stabilizer (14) are both inclined.

3. The large-size ramjet combustion chamber according to claim 2, characterized in that: The inner radial stabilizer (5) and the outer radial stabilizer (14) are provided in multiple groups and are evenly arranged along the circumference of the aircraft engine. A pull rod (10) is connected between the outer ring stabilizer (3) and the outer wall (1).

4. The large-size ramjet combustion chamber according to claim 1, characterized in that: The cross sections of the head and tail of the pre-combustion chamber (6) are both triangular, and the tip of the head of the pre-combustion chamber (6) faces the front end of the engine, while the tip of the tail of the pre-combustion chamber (6) faces the rear end of the engine.

5. The large-size ramjet combustion chamber according to claim 4, characterized in that: The pre-combustion chamber (6) is of integrated design, and is formed by 3D printing.

6. The large-size ramjet combustion chamber according to claim 1, characterized in that: A cooling air duct (11) is also provided in the support plate (7), one end of the cooling air duct (11) is connected to the outer cooling channel of the ramjet engine, and the other end is connected to the interior of the pre-combustion chamber (6).

7. The large-size ramjet combustion chamber according to claim 1, characterized in that: The outer wall (1) is provided with a pressure diffuser and deceleration section, the pressure diffuser and deceleration section adopts a constant pressure gradient shape, and the equivalent expansion angle of the pressure diffuser and deceleration section is 12 to 18 degrees.

8. The large-size ramjet combustion chamber according to claim 1, characterized in that: An anti-vibration and heat-insulating screen (2) is provided on the inner side of the outer wall (1); the anti-vibration and heat-insulating screen (2) is provided at the rear end of the stabilizer; and cooling holes are provided on the anti-vibration and heat-insulating screen (2).

9. The large-size ramjet combustion chamber according to claim 1, characterized in that: The bleed air duct (8) is capable of introducing bleed air from the turbine engine's external fan.

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