A simulation device for hypersonic fuel injection mixing and oblique detonation combustion

Abstract

This invention discloses a hypersonic fuel injection mixing and oblique detonation combustion simulation device, comprising a combustion chamber. An injection support plate assembly is installed at the end of the combustion chamber near the air inlet, and an inducing oblique wedge is installed at the end of the combustion chamber near the outlet. The injection support plate assembly includes a first injection support plate and a second injection support plate. The first injection support plate includes a leading edge plate, a transition plate, and a trailing edge plate, with fuel injection holes on both sides of the trailing edge plate. The second injection support plate has the same structure as the first injection support plate. This invention, by installing two injection support plates at the front end of the combustion chamber and designing injection holes on both sides of the trailing edge of the support plates, allows for better mixing of fuel with the incoming air. The inclined design of the leading and trailing edges of the support plates, with a flat transition in the middle, reduces the total pressure loss within the flow channel. The fuel injection process is easy to control, achieving excellent mixing uniformity within a very short time and distance, making it more suitable for engineering applications.

Description

Technical Field

[0001] This invention belongs to the field of aerospace propulsion technology, specifically relating to a hypersonic fuel injection mixing and oblique detonation combustion simulation device. Background Technology

[0002] Driven by the development needs of fields such as air-breathing high-speed propulsion systems, detonation combustion, as a highly efficient combustion mode, has attracted widespread attention from researchers both domestically and internationally. Among them, oblique detonation combustion is a combustion mode in which shock waves and the combustion process are coupled and mutually reinforced. Compared to the isobaric combustion used in traditional air-breathing ramjet engines, oblique detonation combustion has technical advantages such as high cycle efficiency, fast heat release rate, and self-pressurization. Engines based on oblique detonation combustion can theoretically significantly reduce the complexity of the inlet compression components and shorten the combustion chamber size, thus being considered a highly promising technological breakthrough direction for higher Mach number air-breathing aircraft.

[0003] However, oblique detonation engines require a high degree of fuel mixing, with the fuel needing to be injected and mixed within an extremely short time and distance. The incoming air and fuel must be uniformly mixed before entering the detonation combustion chamber, while premature combustion of the fuel during injection and mixing must be avoided. Within the confined hypersonic flow path, insufficient or uneven mixing of fuel and air may prevent the oblique detonation wave from establishing on the induced wedge, rendering the oblique detonation engine inoperable. Therefore, the challenges of mixing the incoming air and fuel, as well as the initiation of the oblique detonation wave, need to be addressed before the oblique detonation engine can operate.

[0004] Therefore, there is an urgent need for a simulation device that can simulate the mixing of incoming flow and fuel, as well as the detonation process of oblique detonation waves. Summary of the Invention

[0005] In view of the above-mentioned shortcomings and defects of the prior art, the purpose of the present invention is to provide a hypersonic fuel injection mixing and oblique detonation combustion simulation device, thereby solving the problem that there is no device in the prior art for simulating fuel injection mixing and oblique detonation combustion.

[0006] To solve the above-mentioned technical problems, the present invention adopts the following technical solution: a hypersonic fuel injection mixing and oblique detonation combustion simulation device, including a combustion chamber, wherein an injection support plate assembly is installed at one end of the combustion chamber near the air inlet, and an induction oblique wedge is installed at one end of the combustion chamber near the combustion chamber outlet.

[0007] The injection support plate assembly includes a first injection support plate and a second injection support plate, wherein the first injection support plate and the second injection support plate are arranged in parallel and the first injection support plate and the second injection support plate are at the same distance from the air inlet.

[0008] The first injection support plate includes a front edge plate, a transition plate, and a rear edge plate connected in sequence. The front edge plate faces the air inlet side of the combustion chamber, and the rear edge plate faces the combustion chamber outlet side of the combustion chamber.

[0009] Fuel injection holes are provided on both sides of the rear edge plate.

[0010] The second injection support plate has the same structure as the first injection support plate.

[0011] The present invention also has the following technical features:

[0012] The first injection support plate has a double wedge-shaped cross section with a central flat plate, and the overall width w2 of the first injection support plate ranges from 70mm to 90mm.

[0013] The front edge plate has an isosceles triangle cross section with a vertex angle β ranging from 15° to 25°, and the bottom surface of the front edge plate is connected to the transition plate.

[0014] The transition plate has a rectangular cross-section, with a height h ranging from 8mm to 15mm and a width w1 ranging from 10mm to 20mm.

[0015] The rear edge plate has an isosceles triangle cross section, and the bottom surface of the rear edge plate is connected to the transition plate.

[0016] The distance between the injection support plate assembly and the air inlet is 50mm to 65mm.

[0017] The distance between the first injection support plate and the top plate of the combustion chamber is 35mm to 40mm.

[0018] The distance between the second injection support plate and the combustion chamber bottom plate is 35mm to 40mm.

[0019] The transition plate has a fuel chamber inside, which is connected to the fuel injection hole.

[0020] The distance between the fuel injection holes is 2mm to 4mm, and the diameter of the fuel injection holes is 0.5mm to 1.5mm.

[0021] The angle between the fuel injection hole and the horizontal direction is 30° to 90°.

[0022] The rear edge plate has right-angled grooves on both sides, and the outlet of the fuel injection hole is located in the right-angled groove and is perpendicular to the side of the right-angled groove.

[0023] The induction wedge is installed at the combustion chamber outlet, with its rear surface parallel to the combustion chamber outlet surface and at a distance of 0. The lower surface of the wedge is 0mm to 30mm from the lower wall of the combustion chamber.

[0024] The wedge angle θ of the induced wedge is in the range of 20° to 35°.

[0025] The angle range of the rear expansion section of the combustion chamber is 40° to 50°.

[0026] Compared with the prior art, the beneficial technical effects of this invention are: (I) The hypersonic fuel injection mixing and oblique detonation combustion simulation device of the present invention, by installing two injection support plates at the front end of the combustion chamber and designing injection holes on both sides of the rear edge of the support plates, allows the fuel to mix well with the incoming air. The front and rear edges of the support plates are both designed with bevels, and the middle part is transitioned with a flat surface, which can reduce the total pressure loss in the flow channel. The fuel injection process is easy to control, and good mixing uniformity can be achieved within a very short time and distance. It can be used to simulate the mixing of incoming air and fuel and the oblique detonation wave initiation process, and is suitable for engineering applications.

[0027] (II) The hypersonic fuel injection mixing and oblique detonation combustion simulation device of the present invention has a modular design for inducing oblique detonation, and its position is easy to adjust. Under different mixing conditions and different fuel systems, the oblique detonation wave can achieve stable initiation and stationary detonation. Attached Figure Description

[0028] Figure 1 This is a schematic diagram of the overall structure of the hypersonic fuel injection mixing and oblique detonation combustion simulation device of the present invention.

[0029] Figure 2 This is a schematic diagram of the structure of the first injection support plate of the present invention.

[0030] Figure 3 This is a schematic diagram of the induced wedge structure of the present invention.

[0031] Figure 4 This is a two-dimensional structural diagram of the present invention.

[0032] Figure 5 This is a cloud map showing the H2 mass fraction distribution of fuel obtained through two-dimensional numerical simulation in this invention.

[0033] Figure 6 This invention presents the trend of mixing uniformity variation obtained through two-dimensional numerical simulation.

[0034] Figure 7 This is a contour map of oblique detonation combustion pressure obtained by two-dimensional numerical simulation in this invention.

[0035] Figure 8 This is a cloud map of the OH radical distribution obtained by two-dimensional numerical simulation in this invention.

[0036] Figure 9 This is a cloud map showing the distribution of H2O, the product obtained through two-dimensional numerical simulation in this invention.

[0037] The meanings of the labels in the attached diagram are as follows: 1-Combustion chamber, 2-Injection support plate assembly, 3-Inducing oblique wedge.

[0038] 2-1-First injection support plate, 2-2-Second injection support plate.

[0039] 2-1-1-Leading edge plate, 2-1-2-Transition plate, 2-1-3-Rearing edge plate, 2-1-4-Fuel injection hole, 2-1-5-Fuel chamber.

[0040] The specific content of the present invention will be further explained in detail below with reference to the embodiments. Detailed Implementation

[0041] It should be noted that, unless otherwise specified, all raw materials used in this invention are those known in the prior art.

[0042] The following are specific embodiments of the present invention. It should be noted that the present invention is not limited to the following specific embodiments. All equivalent modifications made based on the technical solutions of this application fall within the protection scope of the present invention.

[0043] Example 1: A hypersonic fuel injection mixing and oblique detonation combustion simulation device, such as Figures 1-3 As shown, a hypersonic fuel injection mixing and oblique detonation combustion simulation device includes a combustion chamber 1. An injection support plate assembly 2 is installed at one end of the combustion chamber 1 near the air inlet, and an induction wedge 3 is installed at one end of the combustion chamber 1 near the combustion chamber outlet. In the figure, the x-direction is along the length of the combustion chamber 1, the y-direction is along the height of the combustion chamber 1, and the z-direction is along the width of the combustion chamber 1.

[0044] The injection support plate group 2 includes a first injection support plate 2-1 and a second injection support plate 2-2. The first injection support plate 2-1 and the second injection support plate 2-2 are arranged in parallel and the first injection support plate 2-1 and the second injection support plate 2-2 are at the same distance from the air inlet.

[0045] The first injection support plate 2-1 includes a front edge plate 2-1-1, a transition plate 2-1-2, and a rear edge plate 2-1-3 connected in sequence. The front edge plate 2-1-1 faces the air inlet side of the combustion chamber 1, and the rear edge plate 2-1-3 faces the combustion chamber outlet side of the combustion chamber 1.

[0046] Fuel injection holes 2-1-4 are provided on both sides of the rear edge plate 2-1-3.

[0047] The second injection support plate 2-2 has the same structure as the first injection support plate 2-1.

[0048] To reduce the total pressure loss in the flow channel, the front edge plate 2-1-1 and rear edge plate 2-1-3 of the first injection support plate 2-1 and the second injection support plate 2-2 are all designed with slopes, and the middle transition plate 2-1-2 is designed with a flat surface for transition.

[0049] On the inclined surface of the trailing edge plate 2-1-3, multiple fuel injection holes 2-1-4 are designed on its upper and lower surfaces respectively.

[0050] The induced wedge 3 adopts a trapezoidal prism design, with its wedge-shaped surface facing the incoming flow. Air and fuel are injected synchronously into the flow channel, and after mixing, the mixed combustion gas enters the combustion chamber's detonation zone. Under the action of the induced wedge 3, detonation combustion occurs, forming an oblique detonation wave. The combustion products are accelerated and discharged from the outlet, generating thrust.

[0051] This invention employs an internal pressure-type support plate injection design, using multiple injection holes to achieve fuel injection and mixing, thereby improving fuel mixing uniformity and providing strong support for oblique detonation combustion. The fuel injection process is easy to control, achieving excellent mixing effects within a very short time and distance. It can be used to simulate the mixing of incoming flow and fuel, as well as the oblique detonation wave initiation process, and is suitable for engineering applications.

[0052] As a preferred embodiment: like Figure 2 As shown, the cross-section of the first injection support plate 2-1 is a double wedge shape with a central flat plate, and the overall width w2 of the first injection support plate 2-1 ranges from 70mm to 90mm.

[0053] As a preferred embodiment: like Figure 2 As shown, the cross-section of the leading edge plate 2-1-1 is an isosceles triangle with a vertex angle β ranging from 15° to 25°, and the bottom surface of the leading edge plate 2-1-1 is connected to the transition plate 2-1-2.

[0054] The transition plate 2-1-2 has a rectangular cross-section, with a height h ranging from 8mm to 15mm and a width w1 ranging from 10mm to 20mm.

[0055] The rear edge plate 2-1-3 has an isosceles triangle cross section, and the bottom surface of the rear edge plate 2-1-3 is connected to the transition plate 2-1-2.

[0056] As a preferred embodiment: The distance between the injection support plate assembly 2 and the air inlet is 50mm to 65mm.

[0057] The distance between the first injection support plate 2-1 and the top plate of the combustion chamber 1 is 35mm to 40mm.

[0058] The distance between the second injection support plate 2-2 and the bottom plate of the combustion chamber 1 is 35mm to 40mm.

[0059] As a preferred embodiment: like Figure 2 As shown, the transition plate 2-1-2 has a fuel chamber 2-1-5 inside, and the fuel chamber 2-1-5 is connected to the fuel injection hole 2-1-4.

[0060] The distance between the fuel injection holes 2-1-4 is 2mm to 4mm, and the diameter of the fuel injection holes 2-1-4 is 0.5mm to 1.5mm.

[0061] The angle between the fuel injection hole 2-1-4 and the horizontal direction is 30° to 90°.

[0062] As a preferred embodiment: like Figure 4 As shown, right-angled grooves are provided on both sides of the rear edge plate 2-1-3, and the outlet of the fuel injection hole 2-1-4 is opened in the right-angled groove and is perpendicular to the side of the right-angled groove.

[0063] As a preferred embodiment: The induced wedge 3 is installed at the combustion chamber outlet, with its rear surface parallel to the combustion chamber outlet surface and at a distance of 0. The lower surface of the wedge is 0mm to 30mm from the lower wall of the combustion chamber.

[0064] The wedge angle θ of the induced wedge 3 is in the range of 20° to 35°.

[0065] The height of the wedge along the y-direction ranges from 50mm to 70mm, and the length of the bottom of the wedge along the x-direction ranges from 120mm to 150mm.

[0066] As a preferred embodiment: The angle range of the tail expansion section of the combustion chamber 1 is 40° to 50°.

[0067] Application example: This application example presents a simulation device for hypersonic fuel injection mixing and oblique detonation combustion, referring to... Figure 1 As shown.

[0068] In this application example, the rear edge plate 2-1-3 of the first injection support plate 2-1 and the second injection support plate 2-2 is provided with a plurality of fuel injection holes 2-1-4 along its width direction, as shown in the reference. Figure 2 As shown. Fuel injection orifice angle 2-1-4. αThe angle is set to 60°, the diameter of fuel injection holes 2-1-4 is set to 1mm, the distance between fuel injection holes 2-1-4 is set to 3mm, and the number of fuel injection holes 2-1-4 is set to 60.

[0069] Transition plate 2-1-2 width w 1 is set to 15mm, overall width w 2 is set to 83mm, height h Set to 12mm, bevel angle β Set to 20°.

[0070] In this application example, the fuel injection support plate is installed 58mm away from the air inlet, the first injection support plate 2-1 is 37.5mm away from the top plate of combustion chamber 1, and the second injection support plate 2-2 is 37.5mm away from the bottom plate of combustion chamber 1.

[0071] In this application example, the wedge is designed as a trapezoidal quadrangular prism, refer to... Figure 3 As shown. Its wedge angle θ Set the angle to 30°, the wedge height to 60mm, and the wedge length to 140mm.

[0072] In this application example, the wedge is installed at the combustion chamber outlet, with its rear surface parallel to the combustion chamber outlet surface and at a distance of 0. The lower surface of the wedge is 30mm from the lower wall of the combustion chamber.

[0073] In this application example, to better understand the hypersonic fuel injection mixing and oblique detonation combustion simulation device, refer to... Figure 4 A schematic diagram of its two-dimensional model structure is given, and numerical simulations of fuel injection mixing and oblique detonation wave initiation are carried out using the two-dimensional model.

[0074] In this application example, refer to Figure 4 The hypersonic flow enters the combustion chamber through the air inlet, while fuel is simultaneously injected through fuel injection holes 2-1-4, mixing with the air within the flow channel. Due to the upper and lower double support plates, with injection holes on both sides of the support plates, the mixture achieves a high degree of uniformity upon reaching the detonation section. Subsequently, the mixture enters the detonation section to complete the initiation and stabilization of the oblique detonation wave, and the combustion products are accelerated out of the outlet.

[0075] In this application example, the fuel supply system is connected to the side of the injection support plate assembly 2, and the fuel enters the fuel chamber 2-1-5 and is ejected from the fuel injection hole 2-1-4.

[0076] In this application example, both the first injection support plate 2-1 and the second injection support plate 2-2 have 60 fuel injection holes 2-1-4, with 30 fuel injection holes 2-1-4 on each side.

[0077] The first injection support plate 2-1, the second injection support plate 2-2, and the induced wedge 3 are modularly designed for easy replacement.

[0078] In this application example, hydrogen, ethylene, and kerosene are preferred fuels.

[0079] This application example refers to Figure 5 As shown, this is a schematic diagram of the H2 mass fraction distribution obtained using hydrogen fuel injection. The fuel mixes with air in the flow channel and converges towards the center when it reaches above the induced wedge 3.

[0080] This application example refers to Figure 6 As shown, the fuel mixing uniformity can reach 0.92 when it reaches the detonation section, which strongly supports the detonation of the oblique detonation wave.

[0081] This application example refers to Figure 7 As shown, this is a pressure cloud diagram of detonation combustion using hydrogen fuel above the induced wedge 3. The diagram shows that the detonation wave was successfully initiated, and its wave system structure is a typical "sudden jump" type.

[0082] This application example refers to Figure 8 As shown, this is an OH radical cloud map when hydrogen fuel undergoes detonation combustion above the induced wedge 3. It can be observed in the figure that no OH radical distribution appears in the flow channel except in the area above the wedge, indicating that the fuel does not undergo pre-combustion in the flow channel.

[0083] This application example refers to Figure 9 As shown, this is a cloud map of the H2O product generated when hydrogen fuel undergoes detonation combustion above the induced wedge 3. It can be observed in the figure that detonation combustion only occurred above the induced wedge 3 to generate H2O.

[0084] This application example refers to Figure 5 , Figure 6 , Figure 7 , Figure 8 and Figure 9 Numerical simulation results verified the rationality of the fuel injection mixing and combustion chamber configuration design of the hypersonic fuel injection mixing and oblique detonation combustion simulation device of the present invention.

[0085] The above description is merely a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any changes or substitutions conceived by those skilled in the art within the scope of the technology disclosed in the present invention without creative effort are covered within the scope of protection of the present invention.

Claims

1. A hypersonic fuel injection mixing and oblique detonation combustion simulation device, comprising a combustion chamber (1), wherein an injection support plate assembly (2) is installed at one end of the combustion chamber (1) near the air inlet, and an induction wedge (3) is installed at one end of the combustion chamber (1) near the combustion chamber outlet, characterized in that, The injection support plate assembly (2) includes a first injection support plate (2-1) and a second injection support plate (2-2). The first injection support plate (2-1) and the second injection support plate (2-2) are arranged in parallel and the first injection support plate (2-1) and the second injection support plate (2-2) are at the same distance from the air inlet. The first injection support plate (2-1) includes a front edge plate (2-1-1), a transition plate (2-1-2), and a rear edge plate (2-1-3) connected in sequence. The front edge plate (2-1-1) faces the air inlet side of the combustion chamber (1), and the rear edge plate (2-1-3) faces the combustion chamber outlet side of the combustion chamber (1). Fuel injection holes (2-1-4) are provided on both sides of the rear edge plate (2-1-3). The second injection support plate (2-2) has the same structure as the first injection support plate (2-1).

2. The hypersonic fuel injection mixing and oblique detonation combustion simulation device as described in claim 1, characterized in that, The first injection support plate (2-1) has a double wedge shape with a flat plate in the middle, and the overall width w2 of the first injection support plate (2-1) ranges from 70mm to 90mm.

3. The hypersonic fuel injection mixing and oblique detonation combustion simulation device as described in claim 2, characterized in that, The front edge plate (2-1-1) has an isosceles triangle cross section with a vertex angle β ranging from 15° to 25°. The bottom surface of the front edge plate (2-1-1) is connected to the transition plate (2-1-2). The transition plate (2-1-2) has a rectangular cross-section, with a height h ranging from 8mm to 15mm and a width w1 ranging from 10mm to 20mm. The rear edge plate (2-1-3) has an isosceles triangle cross section, and the bottom surface of the rear edge plate (2-1-3) is connected to the transition plate (2-1-2).

4. The hypersonic fuel injection mixing and oblique detonation combustion simulation device as described in claim 1, characterized in that, The distance between the injection support plate assembly (2) and the air inlet is 50mm to 65mm; The distance between the first injection support plate (2-1) and the top plate of the combustion chamber (1) is 35mm to 40mm; The distance between the second injection support plate (2-2) and the bottom plate of the combustion chamber (1) is 35mm to 40mm.

5. The hypersonic fuel injection mixing and oblique detonation combustion simulation device as described in claim 1, characterized in that, The transition plate (2-1-2) has a fuel chamber (2-1-5) inside, and the fuel chamber (2-1-5) is connected to the fuel injection hole (2-1-4); The distance between the fuel injection holes (2-1-4) is 2mm to 4mm, and the diameter of the fuel injection holes (2-1-4) is 0.5mm to 1.5mm; The angle between the fuel injection hole (2-1-4) and the horizontal direction is 30° to 90°.

6. The hypersonic fuel injection mixing and oblique detonation combustion simulation device as described in claim 3, characterized in that, The rear edge plate (2-1-3) has right-angled grooves on both sides, and the outlet of the fuel injection hole (2-1-4) is located in the right-angled groove and is perpendicular to the side of the right-angled groove.

7. The hypersonic fuel injection mixing and oblique detonation combustion simulation device as described in claim 3, characterized in that, The induced wedge (3) is installed at the combustion chamber outlet, with its rear surface parallel to the combustion chamber outlet surface and at a distance of 0. The lower surface of the wedge is 0mm to 30mm from the lower wall of the combustion chamber. The wedge angle θ of the induced wedge (3) is in the range of 20°-35°.

8. The hypersonic fuel injection mixing and oblique detonation combustion simulation device as described in claim 1, characterized in that, The tail expansion section of the combustion chamber (1) has an angle range of 40° to 50°.

Images