Support plate of RBCC engine using methane fuel

Abstract

The invention discloses a support plate of an RBCC (Radial Basis Combined Cycle) engine using methane fuel, which comprises a central support plate, the central support plate is provided with a gas leading-in hole from top to bottom, the gas leading-in hole is communicated with an external methane and oxygen mixing chamber, the right side of the central support plate is provided with a rocket hole from right to left, the left end of the rocket hole is communicated with the right side of the gas leading-in hole, and the right end of the rocket hole is communicated with the right side of the gas leading-in hole; the gas guide hole is used for guiding mixed high-temperature gas of methane and oxygen entering from the gas guide hole into the combustion chamber; a methane inlet hole is formed in the top of the central supporting plate from top to bottom, and methane outlet holes communicated with the methane inlet hole are formed in the side walls of the two sides of the central supporting plate; the methane inlet hole is communicated with an external methane gas source, and the methane outlet hole is used for spraying methane entering the central support plate from the methane inlet hole into the isolation section, so that the methane enters the combustion chamber for combustion under the ejection of mixed high-temperature gas of methane and oxygen; according to the invention, methane fuel can be used, so that the RBCC engine can work in a wide range.

Description

Technical Field

[0001] The present invention belongs to the field of rocket-based ramjet combined cycle engines, and in particular relates to a support plate of an RBCC engine using methane fuel. Background Art

[0002] Compared with widely used hydrocarbon fuels such as kerosene, methane has higher thermal stability, which is conducive to the continuous operation and reuse of the engine, and its specific impulse is also high. Compared with hydrogen, methane has a larger specific gravity and is easier to store, making it an ideal substitute for traditional fuels in rocket engines. At the same time, compared with liquid injection, gaseous fuel is easier to diffuse and distribute, forming a more uniform mixture, which helps to improve combustion efficiency. The methane fuel support plate and center support plate of the gaseous nozzle optimize the fuel injection and mixing process to ensure more efficient and stable combustion performance.

[0003] The RBCC engine is a novel combined propulsion system that combines the high thrust-to-weight ratio of a rocket engine with the high specific impulse of a ramjet. This allows the vehicle to achieve a wide range of speeds, from zero takeoff to high Mach number flight, significantly improving mission adaptability and holding great potential for future near-Earth aerospace transportation. However, as the vehicle's flight Mach number increases, the airflow in the combustion chamber exceeds the local speed of sound, resulting in a very short residence time for the fuel and air. This is similar to the time required for the chemical reaction of conventional aviation fuel, making combustion organization in supersonic combustion chambers difficult. Current research on supersonic combustion organization primarily challenges ensuring rapid and uniform fuel diffusion and stable and efficient combustion. Therefore, fuel injection and combustion organization methods are crucial. In larger combustion chambers, wall-injected fuel injection hinders rapid diffusion and mixing of fuel and air, leading to the use of fuel supports to overcome this mixing issue.

[0004] The injector support plays a key role in the mixing and combustion of fuel and oxidizer, directly affecting the efficiency and performance of the engine. Currently, most research focuses on the use of traditional liquid fuels (such as liquid hydrogen, liquid oxygen, etc.), and methane fuel has not yet been widely used and deeply studied. Summary of the Invention

[0005] An object of the present invention is to provide a support plate for an RBCC engine using methane fuel, which can enable the RBCC engine to operate in a wide range using methane fuel.

[0006] The present invention adopts the following technical solution: a support plate for an RBCC engine using methane fuel, comprising: a center support plate, the center support plate being disposed in an isolation section of a combustion chamber, the top of the center support plate being fixed to the top of the inner cavity of the isolation section, a gas inlet hole being formed from top to bottom on the center support plate, the gas inlet hole being connected to a mixing chamber of methane and oxygen from the outside, a rocket hole being formed from right to left on the right side of the center support plate, the left end of the rocket hole being connected to the right side of the gas inlet hole, for guiding the high-temperature mixed gas of methane and oxygen entering through the gas inlet hole into the combustion chamber;

[0007] A methane inlet hole is opened on the top of the central support plate from top to bottom, and a methane outlet hole connected to the methane inlet hole is opened on the side walls of the central support plate; the methane inlet hole is connected to the external methane gas source, and the methane outlet hole is used to spray the methane entering the central support plate from the methane inlet hole into the isolation section, and then the methane enters the combustion chamber and burns under the guidance of the mixed high-temperature gas of methane and oxygen.

[0008] Furthermore, there are three rocket holes, which are evenly spaced from top to bottom.

[0009] Furthermore, a first ejection plate and a second ejection plate are installed in the rocket hole. The first ejection plate and the second ejection plate are symmetrically arranged front to back and cooperate with each other to form an ejection channel. The ejection channel gradually decreases from left to right and then gradually increases.

[0010] Furthermore, the gas inlet hole is arranged close to the combustion chamber, and the methane inlet hole is arranged away from the combustion chamber.

[0011] Furthermore, it also includes: a fuel support plate, which is arranged in the combustion chamber; the top of the fuel support plate is fixed to the top of the inner cavity of the combustion chamber, and a fuel inlet hole is opened on the top of the fuel support plate from top to bottom, and fuel outlet holes connected to the fuel inlet hole are opened on the side walls of the fuel support plate. The fuel inlet hole is connected to the external methane gas source, and the fuel outlet hole is used to spray the methane entering the fuel support plate from the fuel inlet hole into the combustion chamber, so that this part of the methane and the methane entering from the center support plate are burned in the combustion chamber.

[0012] Furthermore, the ratio of the outlet cross-sectional area of ​​all rocket holes of the center support plate to the outlet cross-sectional area of ​​all fuel outlet holes of the fuel support plate is 21.5:1.

[0013] Furthermore, the methane inlet hole and the fuel inlet hole are both elliptical, and the major axis direction is left-right.

[0014] The beneficial effects of the present invention are:

[0015] The present invention can use methane fuel to enable the RBCC engine to operate over a wide range, while achieving efficient combustion in the RBCC engine combustion chamber under different modes, optimizing the injection and combustion process of the methane fuel, and guiding and disturbing the airflow in the combustion chamber through the support plate to fully mix the methane fuel and the oxidizer to form a stable combustion zone, thereby improving combustion efficiency and combustion stability, enhancing the engine's thrust and specific impulse performance, optimizing combustion characteristics and thermal management, and improving the overall performance and reliability of the engine system.

[0016] The center support plate and fuel support plate of the present invention optimize the mixing of fuel and oxidant, so that the fuel can burn more fully, thereby significantly improving the combustion efficiency and enhancing the overall performance of the engine; the fuel support plate forms a low-speed, high-turbulence zone in the combustion chamber, which is conducive to the ignition and stable combustion of the fuel and reduces combustion instability. The rocket on the center support plate plays an ignition and flame stabilization role at low Mach numbers, improving the stability of the engine under various working conditions; maintaining long-term stable injection and combustion performance. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 A side view of the center support plate of the present invention;

[0018] Figure 2 This is a cross-sectional view of the center support plate of the present invention;

[0019] Figure 3 It is a side view of the fuel support plate of the present invention.

[0020] Among them: 100, central support plate; 101, gas inlet hole; 102, rocket hole; 103, methane inlet hole; 104, methane outlet hole; 105, first ejector plate; 106, second ejector plate; 200, fuel support plate; 201, fuel inlet hole; 202, fuel outlet hole. DETAILED DESCRIPTION

[0021] The present invention will be described in detail below with reference to the accompanying drawings and specific embodiments.

[0022] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, the terms "first" and "second" are used for descriptive purposes only, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features. In the description of the present invention, unless otherwise specified, "multiple" means two or more. The "direction" in the present invention is based on the direction of the present invention. Figure 1 Description of the direction of the state.

[0023] The present invention discloses a support plate for an RBCC engine using methane fuel, such as Figure 1 As shown, it includes: a central support plate 100, which is arranged in the isolation section of the combustion chamber. The top of the central support plate 100 is fixed to the top of the inner cavity of the isolation section. The central support plate 100 is provided with a gas inlet hole 101 from top to bottom. The gas inlet hole 101 is connected to the external methane and oxygen mixing chamber. The right side of the central support plate 100 is provided with a rocket hole 102 from right to left. The left end of the rocket hole 102 is connected to the right side of the gas inlet hole 101. The rocket hole 102 is used to guide the high-temperature methane and oxygen mixture entering from the gas inlet hole 101 into the combustion chamber. There are three rocket holes 102, which are evenly spaced from top to bottom. The gas inlet hole 101 is located close to the combustion chamber, and the methane inlet hole 103 is located away from the combustion chamber.

[0024] A methane inlet hole 103 is provided on the top of the central support plate 100 from top to bottom, and a methane outlet hole 104 connected to the methane inlet hole 103 is provided on the side walls of the central support plate 100; the methane inlet hole 103 is connected to the external methane gas source, and the methane outlet hole 104 is used to spray the methane entering the central support plate 100 from the methane inlet hole 103 into the isolation section, and then the methane enters the combustion chamber and burns under the guidance of the mixed high-temperature gas of methane and oxygen.

[0025] The rocket hole 102 is provided with a first ejection plate 105 and a second ejection plate 106. The first ejection plate 105 and the second ejection plate 106 are symmetrically arranged front to back and cooperate with each other to form an ejection channel. The ejection channel gradually decreases from left to right and then gradually increases. Figure 2 shown.

[0026] The present invention further comprises: a fuel support plate 200, such as Figure 3 As shown, the fuel support plate 200 is arranged in the combustion chamber; the top of the fuel support plate 200 is fixed to the top of the inner cavity of the combustion chamber, and a fuel inlet hole 201 is opened on the top of the fuel support plate 200 from top to bottom, and fuel outlet holes 202 connected to the fuel inlet hole 201 are opened on the side walls of the fuel support plate 200. The fuel inlet hole 201 is connected to the external methane gas source, and the fuel outlet holes 202 are used to spray the methane entering the fuel support plate 200 from the fuel inlet hole 201 into the combustion chamber, so that this part of the methane and the methane entering from the center support plate 100 are burned in the combustion chamber.

[0027] The ratio of the outlet cross-sectional area of ​​all rocket holes 102 of the central support plate 100 to the outlet cross-sectional area of ​​all fuel outlet holes 202 of the fuel support plate 200 is 21.5:1. The methane inlet holes 103 and the fuel inlet holes 201 are both elliptical, with the major axis running left to right.

[0028] Example 1

[0029] In this embodiment, the pre-injection pressure of the methane outlet 104 and the fuel outlet 202 is 2 MPa, the flow coefficient of the methane outlet 104 and the fuel outlet 202 is 0.85, and the pressure in the gas inlet 101 and the rocket hole 102 is 3.5 MPa.

[0030] The central support plate 100 designed in this embodiment has a design equivalence ratio of 0.4. 20 methane outlet holes 104 are provided on both sides of the central support plate 100 , for a total of 40 methane outlet holes 104 . The diameter of the methane outlet holes 104 is 1.2 mm.

[0031] The fuel support plate 200 designed in this embodiment has a design equivalence ratio of 1.0. Ten fuel outlet holes 202 are provided on both sides of the fuel support plate 200, for a total of 20 fuel outlet holes 202. The diameter of the fuel outlet holes 202 is 2 mm.

[0032] The cross-sectional area of ​​the methane inlet hole 103 of the central support plate 100 is 2.5 times the sum of the cross-sectional areas of the methane outlet holes 104 .

[0033] The cross-sectional area of ​​the fuel inlet hole 201 of the fuel support plate 200 is 1.8 times the sum of the cross-sectional areas of the fuel outlet holes 202 .

[0034] When the flight Mach number is 4, the incoming air flow rate is 4.6 kg / s. By adjusting the equivalence ratio of the center support plate 100 and the fuel support plate 200, different injection conditions can be achieved, for example:

[0035] Working condition 1: The center support plate 100 is not sprayed, and the fuel support plate 200 is sprayed at an equivalent ratio of 1, with an injection mass of 0.2686 kg / s.

[0036] Working condition 2: The center support plate 100 is injected at an equivalent ratio of 0.4, with an injection mass of 0.1075 kg / s; the fuel support plate 200 is injected at an equivalent ratio of 0.6, with an injection mass of 0.1612 kg / s.

[0037] Working condition 3: The center support plate 100 is injected at an equivalent ratio of 0.2, with an injection mass of 0.0537 kg / s; the fuel support plate 200 is injected at an equivalent ratio of 0.8, with an injection mass of 0.2149 kg / s.

[0038]

[0039]

[0040] This embodiment illustrates that different injection operating conditions can be achieved by adjusting the equivalence ratio of the central support plate 100 and the fuel support plate 200 to adapt to different operating conditions.

[0041] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A support plate for an RBCC engine using methane fuel, characterized in that: include: A central support plate (100), the central support plate (100) is arranged in the isolation section of the combustion chamber, the top of the central support plate (100) is fixed to the top of the inner cavity of the isolation section, a gas introduction hole (101) is provided on the central support plate from top to bottom, the gas introduction hole (101) is connected to the mixing chamber of methane and oxygen in the outside, a rocket hole (102) is provided on the right side of the central support plate (100) from right to left, the left end of the rocket hole (102) is connected to the right side of the gas introduction hole (101), and is used to guide the mixed high-temperature gas of methane and oxygen entering from the gas introduction hole (101) into the combustion chamber; A methane inlet hole (103) is provided on the top of the central support plate (100) from top to bottom, and a methane outlet hole (104) connected to the methane inlet hole (103) is provided on the side walls of the central support plate (100); the methane inlet hole (103) is connected to an external methane gas source, and the methane outlet hole (104) is used to spray the methane entering the central support plate (100) from the methane inlet hole (103) into the isolation section, and then the methane enters the combustion chamber and burns under the induced high-temperature gas of the methane and oxygen mixture.

2. A support plate for a RBCC engine using methane fuel according to claim 1, characterized in that: The rocket holes (102) are provided with three holes, which are evenly spaced from top to bottom.

3. The support plate of a RBCC engine using methane fuel according to claim 1, characterized in that: A first ejection plate (105) and a second ejection plate (106) are installed in the rocket hole (102). The first ejection plate (105) and the second ejection plate (106) are symmetrically arranged front to back and cooperate with each other to form an ejection channel. The ejection channel gradually decreases from left to right and then gradually increases.

4. The support plate of a RBCC engine using methane fuel according to claim 1, characterized in that: The gas introduction hole (101) is arranged close to the combustion chamber, and the methane gas inlet hole (103) is arranged away from the combustion chamber.

5. The support plate of a RBCC engine using methane fuel according to claim 1, characterized in that: Also includes: A fuel support plate (200), wherein the fuel support plate (200) is disposed in the combustion chamber; The top of the fuel support plate (200) is fixed to the top of the inner cavity of the combustion chamber. A fuel inlet hole (201) is provided on the top of the fuel support plate (200) from top to bottom. Fuel outlet holes (202) connected to the fuel inlet hole (201) are provided on the side walls of both sides of the fuel support plate (200). The fuel inlet hole (201) is connected to an external methane gas source. The fuel outlet holes (202) are used to spray the methane entering the fuel support plate (200) from the fuel inlet hole (201) into the combustion chamber, thereby allowing this part of the methane to burn with the methane entering from the center support plate (100) in the combustion chamber.

6. A support plate for a RBCC engine using methane fuel according to claim 5, characterized in that: The ratio of the outlet cross-sectional area of ​​all rocket holes (102) of the central support plate (100) to the outlet cross-sectional area of ​​all fuel outlet holes (202) of the fuel support plate (200) is 21.5:

1.

7. The support plate of a RBCC engine using methane fuel according to claim 5, characterized in that: The methane inlet hole (103) and the fuel inlet hole (201) are both elliptical, and the major axis runs in a left-right direction.

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