A scramjet engine combustion chamber based on an S-bend structure for flame stabilization

Abstract

This invention relates to a scramjet engine combustor based on an S-bend flame stabilizer structure, comprising: an isolation section, an S-bend flame stabilizer section, an expansion section, and a tail nozzle arranged sequentially along the flow direction; and a fuel nozzle disposed on the S-bend flame stabilizer section. The isolation section, S-bend flame stabilizer section, expansion section, and tail nozzle are all hollow structures. The S-bend flame stabilizer section includes: a first arc portion and a second arc portion connected sequentially along the flow direction; the end of the first arc portion is connected to the end of the isolation section, wherein the end of the first central axis portion of the first arc portion is tangent to the end of the central axis of the isolation section; the end of the second arc portion is connected to the end of the expansion section, wherein the end of the second central axis portion of the second arc portion is tangent to the end of the central axis of the expansion section. This invention simplifies the design scheme of existing concave-cavity flame stabilized scramjet engine combustors, allowing for more options in the design of the overall engine configuration.

Description

Technical Field

[0001] This invention relates to the aerospace field, and more particularly to a scramjet engine combustion chamber based on an S-bend structure for flame stabilization. Background Technology

[0002] The combustion chamber is the core component of a ramjet engine. The combustion process in a ramjet engine combustion chamber includes ignition, flame propagation, and flame stabilization. After the air-fuel mixture is ignited, the flame propagates throughout the main combustion zone to maintain stable combustion. However, due to the very high velocity of the incoming airflow in a ramjet engine, which is much greater than the flame propagation velocity, the flame is easily quenched. This is where the flame stabilization device plays a crucial role. The working principle of the flame stabilization device is to establish a low-velocity flow zone within the high-velocity flow field in the combustion chamber. This reduces the airflow velocity in the low-velocity flow zone, allowing the flame to remain in the low-velocity flow zone, acting as a "self-illuminating lamp" as a stable ignition source. However, existing conventional concave-cavity flame stabilizers are structurally limited by their concave configuration, restricting the overall engine design. Furthermore, existing concave-cavity flame stabilizers have limited design options in terms of thermal protection.

[0003] In existing scramjet engines, the S-bend is a crucial internal flow channel component, typically serving as the connection between the intake and combustion chamber. Its unique geometry effectively guides high-speed airflow into the combustion chamber and ensures stable combustion. Current research on the flow within the S-bend primarily focuses on secondary flow and flow separation within the pipe, often aiming to reduce flow losses.

[0004] Based on the similarity between the flow characteristics inside the S-bend and the flame stabilization mechanism of the concave cavity, it can achieve the effect of flame stabilization. Moreover, based on existing research on the flow inside the S-bend and the application of the concave cavity flame stabilizer, this can be achieved through the rational design of the S-bend configuration. Summary of the Invention

[0005] The technical problem to be solved by the present invention is to provide a scramjet engine combustion chamber based on an S-bend structure for flame stabilization.

[0006] To achieve the above-mentioned objective, the present invention provides a scramjet engine combustion chamber based on an S-bend flame stabilizer, comprising: an isolation section, an S-bend flame stabilizer section, an expansion section, and a tail nozzle arranged sequentially along the incoming flow direction, and a fuel nozzle disposed on the S-bend flame stabilizer section.

[0007] The isolation section, the S-bend flame stabilizer section, the expansion section, and the tail nozzle are all hollow structures;

[0008] The S-bend flame stabilizer section includes: a first arc portion and a second arc portion connected sequentially along the incoming flow direction;

[0009] The end of the first arc portion is connected to the end of the isolation segment, wherein the end of the first central axis portion of the first arc portion is tangent to the end of the central axis of the isolation segment of the isolation segment;

[0010] The end of the second arc portion is connected to the end of the expansion segment, wherein the end of the second central axis portion of the second arc portion is tangent to the end of the central axis of the expansion segment.

[0011] According to one aspect of the present invention, the isolation section, the S-bend flame stabilizer section, the expansion section and the tail nozzle are respectively a cylindrical structure with a circular cross-section or a cylindrical structure with a rectangular cross-section.

[0012] According to one aspect of the invention, along the incoming flow direction, the height of the isolation section inlet channel of the isolation section is... The height of the flame stabilizer inlet channel of the S-bend flame stabilizer section The following conditions must be met: .

[0013] According to one aspect of the invention, along the incoming flow direction, the height of the flame stabilizer inlet channel of the S-bend flame stabilizer section is... The height of the flame stabilizer outlet flow channel of the S-bend flame stabilizer section The following conditions must be met: .

[0014] According to one aspect of the invention, the radius of the first central axis portion of the first arc portion is... and the radius of the second central axis portion of the second arc portion. The following conditions must be met: ;

[0015] The central angle of the first central axis portion of the first arc portion and the central angle of the second central axis portion of the second arc portion The following conditions must be met: .

[0016] According to one aspect of the invention, the radius of the first central axis portion of the first arc portion is... Height of the flame stabilizer inlet channel The following conditions must be met: ;

[0017] The central angle of the first central axis portion satisfy: ;

[0018] The second central axis portion of the central angle satisfy: .

[0019] According to one aspect of the invention, in the S-bend flame stabilizer section, the radius of the circular cross-section perpendicular to the central axis of the flame stabilizer section is... Length of the flame stabilizer centerline satisfy:

[0020] .

[0021] According to one aspect of the invention, the isolation segment is a bilaterally expanded circular cross-section isolation segment, and the range of its isolation segment expansion angle is: ;in, This refers to the axial length of the isolation section;

[0022] The expansion segment is a bilaterally expanded circular cross-section expansion segment, and its expansion segment length is... Height of flame stabilizer outlet channel The following conditions must be met: ;

[0023] The expansion section outlet flow channel height Height of flame stabilizer outlet channel The following conditions must be met: .

[0024] According to one aspect of the invention, the first arc portion of the S-bend flame stabilizer section is provided with a fuel injection hole for docking with the fuel nozzle;

[0025] Along the flow direction, the length of the distance from the center of the fuel injection orifice to the front end of the first arc portion satisfy: ;

[0026] Along the horizontal direction, the fuel injection holes are symmetrically arranged on opposite sides of the first arc portion, and the center of the fuel injection hole is flush with the first central axis portion.

[0027] The diameter of the fuel injection orifice satisfies: ;

[0028] The fuel injection orifice satisfies the requirement that the ratio of injection flow pressure to free flow pressure ranges from 2.3 to 5;

[0029] The fuel nozzle has a sonic nozzle configuration, and its injection direction is set perpendicular to the wall surface of the first arc portion.

[0030] According to one aspect of the invention, along the incoming flow direction, the height of the isolation section inlet channel of the isolation section is... The height of the flame stabilizer inlet channel of the S-bend flame stabilizer section The following conditions must be met: ;

[0031] Along the incoming flow direction, the height of the flame stabilizer inlet channel of the S-bend flame stabilizer section The height of the flame stabilizer outlet flow channel of the S-bend flame stabilizer section The following conditions must be met: ;

[0032] The radius of the first central axis portion of the first arc portion and the radius of the second central axis portion of the second arc portion. The following conditions must be met: ;

[0033] The radius of the first central axis portion of the first arc portion Height of the flame stabilizer inlet channel The following conditions must be met: ;

[0034] The central angle of the first central axis portion satisfy: ;

[0035] The second central axis portion of the central angle satisfy: ;

[0036] The isolation segment is a bilaterally expanded circular cross-section isolation segment, and its expansion angle is: ;

[0037] The expansion segment is a bilaterally expanded circular cross-section expansion segment, and its expansion segment length is... Height of flame stabilizer outlet channel The following conditions must be met: ;

[0038] The expansion section outlet flow channel height Height of flame stabilizer outlet channel The following conditions must be met: ;

[0039] The fuel injection orifice satisfies the requirement that the pressure ratio between the injected flow and the free flow is 3.5.

[0040] According to one aspect of the present invention, a design method for a scramjet engine combustor that utilizes an S-bend structure to achieve flame stabilization is provided, which further simplifies the design scheme of the existing concave cavity flame-stabilized scramjet engine combustor, allowing for more choices in the overall engine configuration design, and providing more possibilities for the selection of engine thermal protection schemes.

[0041] According to one aspect of the present invention, a novel design method for the combustion chamber of a scramjet engine is proposed, which appropriately enhances the flow separation phenomenon present in the S-bend and utilizes the flow characteristics of the secondary flow to achieve fuel mixing and flame stability in the bend.

[0042] According to one aspect of the present invention, the present invention makes full use of the S-bend structure to achieve flame stabilization. The S-bend structure, which was originally part of the isolation section, is moved to the position of the traditional concave flame stabilizer. By utilizing the flow separation and secondary flow phenomena present in the S-bend, fuel mixing and subsequent flame stabilization are achieved in the recirculation zone on the upper side of the S-bend, providing a new approach for the design of the scramjet engine combustion chamber.

[0043] According to one aspect of the present invention, a scramjet engine based on the scramjet engine combustion chamber of the present invention can achieve a high-speed cruise state, enabling it to cruise at a speed of Mach 4-6.

[0044] According to one aspect of the present invention, the innovative introduction of an S-bend structure to remove the traditional concave cavity combustion chamber provides a new approach to engine design, which can further shorten the overall length of the combustion chamber and provide more possibilities for the overall engine design. Attached Figure Description

[0045] Figure 1 This is a cross-sectional view of the combustion chamber of a scramjet engine according to one embodiment of the present invention;

[0046] Figure 2 This is a cross-sectional dimension view of the combustion chamber of a scramjet engine according to one embodiment of the present invention;

[0047] Figure 3 This is a top view of an S-bend flame stabilizer section according to one embodiment of the present invention;

[0048] Figure 4 This is a diagram showing the working state of the combustion chamber of a scramjet engine according to one embodiment of the present invention. Detailed Implementation

[0049] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the embodiments will be briefly described below. Obviously, the drawings described below are merely some embodiments of the present invention, and those skilled in the art can obtain other drawings based on these drawings without creative effort.

[0050] In describing embodiments of the present invention, the terms "longitudinal," "lateral," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," and "outer" express orientations or positional relationships based on the orientations or positional relationships shown in the relevant drawings. They are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, the above terms should not be construed as limitations on the present invention.

[0051] The present invention will now be described in detail with reference to the accompanying drawings and specific embodiments. The embodiments cannot be described in detail here, but the embodiments of the present invention are not limited to the following embodiments.

[0052] Combination Figure 1 , Figure 2 and Figure 3 As shown, according to one embodiment of the present invention, a scramjet engine combustion chamber based on an S-bend flame stabilizer includes: an isolation section 1, an S-bend flame stabilizer section 2, an expansion section 3, and a tail nozzle 4 arranged sequentially along the incoming flow direction, and a fuel nozzle disposed on the S-bend flame stabilizer section 2; wherein, the isolation section 1, the S-bend flame stabilizer section 2, the expansion section 3, and the tail nozzle 4 are all hollow structures. Correspondingly, the isolation section 1, the S-bend flame stabilizer section 2, the expansion section 3, and the tail nozzle 4 each have a corresponding central axis.

[0053] In this embodiment, the S-bend flame stabilizer section 2 includes a first arc portion 21 and a second arc portion 22 connected sequentially along the incoming flow direction. The end of the first arc portion 21 is connected to the end of the isolation section 1. The bending directions of the first arc portion 21 and the second arc portion 22 are different, thereby forming the basic shape of the S-bend flame stabilizer section 2. Further, the central axis of the flame stabilizer section of the S-bend flame stabilizer section 2 includes a first central axis portion and a second central axis portion, wherein the first central axis portion and the second central axis portion are arc-shaped and connected tangentially. In this embodiment, the end of the first central axis portion of the first arc portion 21 is tangent to the end of the central axis of the isolation section of the isolation section 1; the end of the second arc portion 22 is connected to the end of the expansion section 3, wherein the end of the second central axis portion of the second arc portion 22 is tangent to the end of the central axis of the expansion section of the expansion section 3, thereby achieving a smooth connection between the isolation section 1, the S-bend flame stabilizer section 2, and the expansion section 3.

[0054] In this embodiment, a pre-burning shock wave train is provided in the isolation section 1 to decelerate and pressurize the incoming flow, thereby achieving a pressure balance between low-pressure intake and high-pressure combustion; the S-bend flame stabilizer section 2 constitutes a combustion chamber to organize combustion, specifically through its S-shaped structure to achieve fuel mixing and flame stabilization within the S-bend, thus eliminating the effect of traditional concave cavity combustion chamber configuration; the expansion section 3 connects the S-bend flame stabilizer section 2 and the tail nozzle 4, with the airflow gradually increasing in speed and decreasing in pressure; the tail nozzle 4 serves as the outlet and is connected to the outside atmosphere.

[0055] Combination Figure 1 , Figure 2 and Figure 3 As shown, according to one embodiment of the present invention, the isolating section 1, the S-bend flame stabilizer section 2, the expansion section 3, and the tail nozzle 4 are respectively cylindrical structures with circular or rectangular cross-sections. Of course, they can also be cylindrical structures with other regular cross-sectional shapes, selected based on corresponding practical needs. Thus, when a cylindrical structure with a circular cross-section is used, the scramjet engine combustion chamber of the present invention can be matched with a corresponding circular cross-section engine; when a cylindrical structure with a rectangular cross-section is used, the scramjet engine combustion chamber of the present invention can be matched with a corresponding rectangular cross-section engine. In this embodiment, the isolating section 1, the S-bend flame stabilizer section 2, the expansion section 3, and the tail nozzle 4 are preferably cylindrical structures with circular cross-sections.

[0056] In this embodiment, along the incoming flow direction, the height of the inlet flow channel of isolation section 1 is... The height of the flame stabilizer inlet flow channel of section 2 of the S-bend flame stabilizer The following conditions must be met: Preferably, the height of the inlet flow channel of isolation section 1 is... The height of the flame stabilizer inlet flow channel of section 2 of the S-bend flame stabilizer Set the value between 1 and 3.

[0057] In this embodiment, along the incoming flow direction, the height of the flame stabilizer inlet channel of the S-bend flame stabilizer section 2 is... The height of the flame stabilizer outlet flow channel of section 2 of the S-bend flame stabilizer The following conditions must be met: Preferably, the height of the flame stabilizer inlet channel of the S-bend flame stabilizer section 2 is... The height of the flame stabilizer outlet flow channel of section 2 of the S-bend flame stabilizer The value between them is set to 1.2.

[0058] By setting the flow channel height ratio at different connection positions within the above range, the stable performance of the present invention is effectively guaranteed, which is especially beneficial for the normal and stable operation of the S-bend flame stabilizer section 2. If the flow channel height ratio is further reduced (i.e., less than the minimum value of the above range), it is easy to cause flow channel blockage. If the flow channel height ratio is further increased (i.e., greater than the maximum value of the above range), it is easy to cause unstable combustion or the flame to be blown out.

[0059] In this embodiment, in the S-bend flame stabilizer section 2, the radius of the first central axis portion of the first arc portion 21 is... The radius of the second central axis portion of the second arc portion 22 The following conditions must be met: Preferably, the radius of the first central axis portion of the first arc portion 21 is... The radius of the second central axis portion of the second arc portion 22 The interval is set to 1; correspondingly, the central angle of the first central axis portion of the first arc portion 21 is... The central angle of the second central axis portion of the second arc portion 22 The following conditions must be met: Furthermore, the first arc portion 21 and the second arc portion 22 are tangentially connected to each other.

[0060] The above settings effectively ensure the accuracy and reliability of the basic configuration of the S-bend flame stabilizer section 2, especially through the central angle of the first central axis section. The central angle of the second central axis The equal relationship between them more accurately ensures the smooth connection between the first arc portion 21 and the second arc portion 22, avoids the formation of protrusions at the connection position, fully ensures the smooth and stable flow of fluid, and provides a reliable guarantee for stable combustion in the S-bend flame stabilizer section 2.

[0061] In this embodiment, the radius of the first central axis portion of the first arc portion 21 is... Height of flame stabilizer inlet channel The following conditions must be met: Preferably, the radius of the first central axis portion of the first arc portion 21 is... Height of flame stabilizer inlet channel The value between them is set to 6.8. The radius of the second central axis portion of the second arc portion 22 is... radius of the arc in the first central axis section Given a certainty, it can be based on the ratio. What was obtained.

[0062] In this embodiment, the central angle of the first central axis portion satisfy: Preferably, the central angle of the first central axis portion The value is 20°.

[0063] In this embodiment, the central angle of the second central axis portion satisfy: Preferably, the central angle of the second central axis portion The value is 20°.

[0064] With the above settings, by adjusting the radius of the arc of the first central axis portion... Height of flame stabilizer inlet channel The setting of the ratio range and the central angle of the first central axis portion The central angle of the second central axis section The size limitation further enhances the flame stabilization function in the S-bend flame stabilizer section 2, which is more beneficial for ensuring the reliable and stable operation of the S-bend flame stabilizer section 2 of this invention, and fully guarantees the corresponding flame stabilization function. If the radius of the arc of the first central axis portion... Too small or the central angle of the first central axis The central angle of the second central axis section If the flame is too large, it can easily cause blockage of the flow channel; conversely, if it is too small, the internal flame can easily become unstable.

[0065] In this embodiment, in the S-bend flame stabilizer section 2, the radius of the circular cross-section perpendicular to the central axis of the flame stabilizer section 2 is... Length of the flame stabilizer centerline satisfy:

[0066] ;

[0067] Among them, the length of the central axis of the flame stabilizer It refers to the length of the central axis extending along the S-shape.

[0068] Furthermore, it should be noted that when the S-bend flame stabilizer section 2 adopts a rectangular cross-section cylindrical structure, the radius of the circular cross-section involved in the above formula will be... The value is the vertical distance between the upper or lower wall surface (i.e., the upper or lower edge of the cross section) and the central axis.

[0069] Therefore, the radius of the circular cross-section perpendicular to the central axis of the flame stabilizer segment 2 of the S-bend is... It is with the length of the flame stabilizer's central axis The flow path height of the flame stabilizer changes uniformly, and thus, when the inlet channel height of the flame stabilizer changes... Flame stabilizer outlet flow channel height The radius of the arc of the first central axis section The radius of the arc of the second central axis section Central angle of the first central axis section The central angle of the second central axis section Once determined, the radius of the circular cross-section Length of the flame stabilizer centerline The rate of change between them is a constant.

[0070] The above settings effectively ensure a smooth transition between internal wall surfaces, completely eliminating abrupt changes on the wall surface.

[0071] Combination Figure 1 , Figure 2 and Figure 3 As shown, according to one embodiment of the present invention, the isolation segment 1 is a double-sided expanded circular cross-section isolation segment, and the range of its isolation segment expansion angle is: ;in, The axial length of isolation segment 1; preferably, the expansion angle of isolation segment 1 is 1.3°; further, expansion segment 3 is a double-sided expanding circular cross-section expansion segment, and its expansion segment length is... Height of flame stabilizer outlet channel The following conditions must be met: Preferably, the length of the expansion segment 3 is... Height of flame stabilizer outlet channel Between The value is 2.5; furthermore, the height of the expansion section outlet flow channel of expansion section 3... Height of flame stabilizer outlet channel The following conditions must be met: Preferably, the height of the expansion section outlet flow channel of expansion section 3 is... Height of flame stabilizer outlet channel Between The value is 1.2.

[0072] The above settings effectively limit the expansion of both the isolation section 1 and the expansion section 3, achieving a match with the structural dimensions of the S-bend flame stabilizer section 2. This is more beneficial for ensuring the stability and reliability of the invention. If the above ratio range is too narrow, it will cause internal blockage; if the above ratio range is too wide, it will make it difficult to stabilize the flame internally.

[0073] Combination Figure 1 , Figure 2 and Figure 3 As shown, according to one embodiment of the present invention, the first arc portion 21 of the S-bend flame stabilizer section 2 is provided with a fuel nozzle 211 for docking with a fuel nozzle; wherein, along the incoming flow direction, the distance from the center of the fuel nozzle 211 to the front end of the first arc portion 21 is... satisfy: In this embodiment, the fuel nozzle 211 is a circular nozzle and a liquid hydrogen nozzle, and the number of such nozzles is preferably 2. Furthermore, along the horizontal direction, the fuel nozzles 211 are symmetrically arranged on both sides of the first arc portion 21, and the nozzle center of the fuel nozzle 211 is flush with the first central axis portion.

[0074] In this embodiment, the diameter of the fuel injection orifice 211 satisfies: .

[0075] In this embodiment, the fuel injection orifice 211 satisfies the pressure ratio of the injected flow to the free flow in the range of 2.3 to 5; preferably, the fuel injection orifice 211 satisfies the pressure ratio of the injected flow to the free flow in the range of 3.5.

[0076] In this embodiment, the fuel nozzle has a sonic nozzle configuration and its injection direction is set perpendicular to the wall of the first arc portion 21, so that the fuel nozzle is set perpendicular to the axial direction of the first arc portion 21.

[0077] Through the above settings, the position of the fuel injection orifice 211 is restricted. This is to ensure that the fuel nozzle 211 is located in the first arc portion 21, so as to ensure that the flame stabilization area is mainly located on the upper side of the second arc portion 22, thus ensuring the stability of the flame stabilization area. If the fuel nozzle 211 is too far back, it will easily cause the flame to be pushed forward, which will seriously affect the positional stability of the flame stabilization area and the mixing combustion efficiency in the S-bend flame stabilizer section 2. In addition, by further limiting the diameter of the fuel nozzle 211 and the pressure ratio between the injected flow and the free flow, it is possible to further ensure that sufficient fuel penetration depth is achieved without generating excessive flow loss, thus further effectively ensuring the mixing combustion efficiency of the present invention. If the pressure ratio between the injected flow and the free flow is too small, the injection will have a serious impact due to insufficient depth. If the pressure ratio between the injected flow and the free flow is too large, it will cause too much disturbance to the incoming flow, resulting in a large total pressure loss of the incoming flow, which is also detrimental to the reliable operation of the S-bend flame stabilizer section 2.

[0078] Based on the above configuration, the operating state of the scramjet engine using the scramjet engine combustion chamber of the present invention is as follows: Figure 4 As shown, the supersonic flow, decelerated by the intake duct, enters from the inlet of isolation section 1. After fuel is injected through the fuel nozzles 211 in the S-bend flame stabilizer section 2, it achieves thorough mixing in the upper recirculation zone. The main recirculation zone is located above the second arc portion 22 of the S-bend flame stabilizer section 2. After ignition, flame stabilization is achieved using the main recirculation zone, as shown in the diagram. Figure 4 As indicated by the label.

[0079] The above description is merely an example of a specific solution of the present invention. For any devices and structures not described in detail herein, it should be understood that they are implemented using common devices and methods already available in the art.

[0080] The above description is merely one embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the invention by those skilled in the art. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A scramjet engine combustion chamber based on an S-bend structure for flame stabilization, characterized in that, include: An isolation section (1), an S-bend flame stabilizer section (2), an expansion section (3), and a tail nozzle (4) are arranged sequentially along the incoming flow direction, and a fuel nozzle is installed on the S-bend flame stabilizer section (2); The isolation section (1), the S-bend flame stabilizer section (2), the expansion section (3) and the tail nozzle (4) are all hollow structures; The S-bend flame stabilizer section (2) includes: a first arc portion (21) and a second arc portion (22) connected sequentially along the incoming flow direction; The end of the first arc portion (21) is connected to the end of the isolation segment (1), wherein the end of the first central axis portion of the first arc portion (21) is tangent to the end of the central axis of the isolation segment (1); The end of the second arc portion (22) is connected to the end of the expansion segment (3), wherein the end of the second central axis portion of the second arc portion (22) is tangent to the end of the central axis of the expansion segment of the expansion segment (3).

2. The scramjet engine combustion chamber based on an S-bend structure for flame stabilization according to claim 1, characterized in that, The isolation section (1), the S-bend flame stabilizer section (2), the expansion section (3), and the tail nozzle (4) are respectively a cylindrical structure with a circular cross-section or a cylindrical structure with a rectangular cross-section.

3. The scramjet engine combustion chamber based on an S-bend structure for flame stabilization according to claim 2, characterized in that, Along the direction of incoming flow, the height of the inlet flow channel of the isolation section (1) The height of the flame stabilizer inlet channel of the S-bend flame stabilizer section (2) The following conditions must be met: .

4. The scramjet engine combustion chamber based on an S-bend structure for flame stabilization according to claim 3, characterized in that, Along the incoming flow direction, the height of the flame stabilizer inlet channel of the S-bend flame stabilizer section (2) The height of the flame stabilizer outlet flow channel of the S-bend flame stabilizer section (2) The following conditions must be met: .

5. The scramjet engine combustion chamber based on an S-bend structure for flame stabilization according to claim 4, characterized in that, The radius of the first central axis portion of the first arc portion (21) and the radius of the second central axis portion of the second arc portion (22) The following conditions must be met: ; The central angle of the first central axis portion of the first arc portion (21) The central angle of the second central axis portion of the second arc portion (22) The following conditions must be met: .

6. The scramjet engine combustion chamber based on an S-bend structure for flame stabilization according to claim 5, characterized in that, The radius of the first central axis portion of the first arc portion (21) Height of the flame stabilizer inlet channel The following conditions must be met: ; The central angle of the first central axis portion satisfy: ; The second central axis portion of the central angle satisfy: .

7. The scramjet engine combustion chamber based on an S-bend structure for flame stabilization according to claim 6, characterized in that, The radius of the circular cross-section perpendicular to the central axis of the flame stabilizer in the S-bend flame stabilizer section (2) is... Length of the flame stabilizer centerline satisfy: 。 8. The scramjet engine combustion chamber based on an S-bend structure for flame stabilization according to claim 7, characterized in that, The isolation segment (1) is a bilaterally expanded circular cross-section isolation segment, and the range of its expansion angle is as follows: ;in, The axial length of the isolation section (1); The expansion segment (3) is a bilaterally expanded circular cross-section expansion segment, and its expansion segment length is... Height of flame stabilizer outlet channel The following conditions must be met: ; The expansion section (3) outlet flow channel height Height of flame stabilizer outlet channel The following conditions must be met: .

9. The scramjet engine combustion chamber based on an S-bend structure for flame stabilization according to claim 8, characterized in that, The first arc portion (21) of the S-bend flame stabilizer section (2) is provided with a fuel nozzle (211) for docking with the fuel nozzle. Along the flow direction, the distance from the center of the fuel injection orifice (211) to the front end of the first arc portion (21) is... satisfy: ; Along the horizontal direction, the fuel injection holes (211) are symmetrically arranged on opposite sides of the first arc portion (21), and the center of the fuel injection holes (211) is flush with the first central axis portion. The diameter of the fuel injection orifice (211) satisfies: ; The fuel injection orifice (211) satisfies the requirement that the ratio of the injection flow pressure to the free flow pressure ranges from 2.3 to 5; The fuel nozzle has a sonic nozzle configuration and its injection direction is set perpendicular to the wall surface of the first arc portion (21).

10. The scramjet engine combustion chamber based on an S-bend structure for flame stabilization according to claim 9, characterized in that, Along the direction of incoming flow, the height of the inlet flow channel of the isolation section (1) The height of the flame stabilizer inlet channel of the S-bend flame stabilizer section (2) The following conditions must be met: ; Along the incoming flow direction, the height of the flame stabilizer inlet channel of the S-bend flame stabilizer section (2) The height of the flame stabilizer outlet flow channel of the S-bend flame stabilizer section (2) The following conditions must be met: ; The radius of the first central axis portion of the first arc portion (21) and the radius of the second central axis portion of the second arc portion (22) The following conditions must be met: ; The radius of the first central axis portion of the first arc portion (21) Height of the flame stabilizer inlet channel The following conditions must be met: ; The central angle of the first central axis portion satisfy: ; The second central axis portion of the central angle satisfy: ; The isolation segment (1) is a bilaterally expanded circular cross-section isolation segment, and its expansion angle is: ; The expansion segment (3) is a bilaterally expanded circular cross-section expansion segment, and its expansion segment length is... Height of flame stabilizer outlet channel The following conditions must be met: ; The expansion section (3) outlet flow channel height Height of flame stabilizer outlet channel The following conditions must be met: ; The fuel injection orifice (211) satisfies the requirement that the pressure ratio between the injected flow and the free flow is 3.5.

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