Adaptive regulation injection device and method for high-speed engine combustion chamber

Abstract

The application discloses a self-adaptive adjusting injection device and method of a high-speed engine combustion chamber, which comprises a base, a rigid pipe body and an elastic pipe body. The rigid pipe body is connected with the base at one end in the axial direction. The side wall of the rigid pipe body is provided with a cooling flow channel. The elastic pipe body is arranged at the inner side of the rigid pipe body and connected with the base at one end in the axial direction. The pipe hole of the elastic pipe body is an injection channel. The injection channel can self-adaptively adjust the aperture of the pipe hole. The fuel in the cooling flow channel of the side wall of the combustion chamber is used for cooling and heat absorbing the wall surface of the combustion chamber. When the fuel which does not change phase is introduced into the injection channel, the elastic pipe body keeps the original state. When the fuel which changes phase is introduced into the injection channel, the elastic pipe body is deformed by the expansion of the fuel, and the diameter of the fuel channel is increased. The application can self-adaptively adjust the aperture of the injection channel, ensure the penetration depth of the fuel with large density at a small aperture, and avoid the flow limitation of the fuel with small density at a large aperture.

Description

Technical Field

[0001] This invention relates to the field of high-speed engine combustion chamber wall cooling, and in particular to an adaptive adjustment injection device and method for a high-speed engine combustion chamber. Background Technology

[0002] High-speed engine combustion chambers have different flight conditions in different application scenarios. These changes in flight conditions are accompanied by a large heat flow to the walls, requiring active cooling circulation of fuel to reduce wall erosion. Under some flight conditions, the high-temperature fuel that has completed the circulation also needs to be burned to improve combustion performance.

[0003] When a high-speed engine is flying at low Mach numbers, the heat flux across the walls is relatively small. At this time, the fuel in the active cooling cycle is pure liquid fuel; for example, kerosene has a density of approximately 780 kg / m³. 3 When a high-speed engine flies at high Mach numbers, the fuel undergoes rapid changes in physical properties as it cools and absorbs heat from the combustion chamber walls. This is especially true due to density changes caused by phase transitions and the rapid decrease in density with increasing temperature in the gaseous phase. As the fuel temperature rises, the proportion of gaseous fuel gradually increases, and once it is completely vaporized, its density decreases rapidly. Kerosene is in a fully supercritical state with a density of approximately 100 kg / m³. 3 .

[0004] Traditional injection channels, being constructed of rigid materials, have a fixed orifice diameter. If this orifice diameter is suitable for high-speed engines operating at low Mach numbers, it doesn't need to be too large; however, using a large-diameter injector results in extremely low fuel penetration, leading to poor combustion chamber performance in high-speed engines. Conversely, if the orifice diameter is suitable for high-speed engines operating at high Mach numbers, it needs to be larger; using a small-diameter injector would restrict fuel flow, failing to achieve the design equivalence ratio of the high-speed engine's combustion chamber.

[0005] Traditional injection devices, when using small orifices, are prone to flow restriction due to orifice size limitations. High-temperature two-phase or gaseous fuels, with their lower density, are restricted during injection due to the mismatch between the orifice size and the limited injection channel. Conversely, when using large orifices, the initial liquid fuel or two-phase fuel has a higher density. To ensure the design flow rate, the fuel's unit flow volume is small, resulting in slow fuel velocity and extremely low penetration depth. In supersonic flow, the fuel almost adheres to the wall, significantly impacting the combustion chamber performance of high-speed engines. Ensuring sufficient penetration depth for denser fuels while avoiding flow restriction for less dense fuels is a pressing technical problem that needs to be solved in this field. Summary of the Invention

[0006] Therefore, the present invention provides an adaptive adjustment injection device and method for the combustion chamber of a high-speed engine, which can adaptively adjust the orifice diameter of the injection channel to ensure the penetration depth of the denser fuel while avoiding the flow restriction of the less dense fuel.

[0007] To solve the above-mentioned technical problems, the present invention provides an adaptive adjustment injection device for a high-speed engine combustion chamber, comprising a base, a rigid tube, and an elastic tube. One end of the rigid tube is connected to the base along the axial direction, and a cooling channel is provided on the side wall of the rigid tube. The elastic tube is located inside the rigid tube, and one end of the elastic tube is connected to the base along the axial direction. The orifice of the elastic tube is an injection channel, and the orifice diameter of the injection channel can be adaptively adjusted.

[0008] Optionally, the rigid tube body is made of fiber-reinforced ceramic matrix composite material, which is a composite of ceramic and fiber.

[0009] Optionally, the elastic tube body is made of a metal-rubber material produced by spiral winding, weaving blanks, or stamping.

[0010] Optionally, one end of the elastic tube along the axial direction is connected to the base through a plurality of connection points evenly distributed along the circumference.

[0011] Optionally, when the elastic tube is in its original state, its wall is spaced a certain distance from the wall of the rigid tube.

[0012] Optionally, the rigid tube has a frustum-shaped bore, the small opening of the rigid tube is connected to the base, the elastic tube has a cylindrical outer contour, the outer diameter of the end of the elastic tube connected to the base is equal to the inner diameter of the end of the rigid tube connected to the base, and the outer diameter of the end of the elastic tube away from the base is smaller than the inner diameter of the end of the rigid tube away from the base.

[0013] Optionally, the base and the rigid tube are an integral structure.

[0014] Optionally, the cooling channels on the combustion chamber sidewall and the cooling channels on the rigid tube sidewall are integral channels.

[0015] Optionally, the cooling channel is a tortuous channel.

[0016] The present invention also provides an adaptive adjustment injection method for a high-speed engine combustion chamber. Using the aforementioned adaptive adjustment injection device, the fuel in the cooling channel of the combustion chamber sidewall cools and absorbs heat from the combustion chamber wall. When fuel that has not undergone phase change is introduced into the injection channel, the elastic tube remains in its original state. When fuel that has undergone phase change is introduced into the injection channel, the elastic tube deforms and its orifice diameter increases.

[0017] Compared with the prior art, the above-mentioned technical solution of the present invention has the following advantages: The adaptive adjustment injection device and method for the high-speed engine combustion chamber of the present invention includes a base, a rigid tube, and an elastic tube. The injection device can change the orifice size according to the changes in fuel properties under different wall heat flux densities during the operation of the high-speed engine combustion chamber, so as to simultaneously meet the requirements of unrestricted fuel flow or insufficient penetration depth at various operating points, ensuring that the high-speed engine combustion chamber can operate normally within its own operating range. When the high-speed engine is running at low Mach numbers, the original diameter or a small deformation diameter is maintained under the working medium of gas-liquid two-phase fuel, ensuring sufficient fuel penetration depth. When the fuel becomes gaseous at high Mach numbers and its density decreases, the metal rubber layer of the injection device deforms to expand the injection orifice size, avoiding fuel flow restriction. Attached Figure Description

[0018] To make the content of this invention easier to understand, the invention will be further described in detail below with reference to specific embodiments and accompanying drawings.

[0019] Figure 1 This is a schematic diagram of the adaptive adjustment injection device for the combustion chamber of a high-speed engine disclosed in this invention under one working state. Figure 2 This is a schematic diagram of another working state of the adaptive adjustment injection device for the combustion chamber of a high-speed engine disclosed in this invention.

[0020] Explanation of the markings in the accompanying drawings: 1. Base; 11. Connection point; 2. Rigid tube; 21. Cooling channel; 3. Elastic tube; 31. Injection channel. Detailed Implementation

[0021] The present invention will be further described below with reference to the accompanying drawings and specific embodiments, so that those skilled in the art can better understand and implement the present invention. However, the embodiments described are not intended to limit the present invention.

[0022] See Figure 1 and Figure 2 As shown, this invention discloses an embodiment of an adaptive adjustment injection device for a high-speed engine combustion chamber.

[0023] An adaptive adjustment injection device for a high-speed engine combustion chamber includes a base 1, a rigid tube 2, and an elastic tube 3. One end of the rigid tube 2 along the axial direction is connected to the base 1. The side wall of the rigid tube 2 is provided with a cooling channel 21. The elastic tube 3 is located inside the rigid tube 2, and one end of the elastic tube 3 along the axial direction is connected to the base 1. The tube hole of the elastic tube 3 is an injection channel 31, and the injection channel 31 can adaptively adjust the diameter of the tube hole.

[0024] Specifically, the aforementioned injection device is used to inject fuel into the combustion chamber, and the injection device as a whole must be able to withstand the high temperatures inside the combustion chamber. The base 1 serves as the installation reference for the injection device, connecting the rigid tube 2 and the elastic tube 3 into a single unit. The main function of the rigid tube 2 is to provide a load-bearing frame, constraining the elastic tube 3 and preventing excessive expansion. Simultaneously, it acts as a carrier for the cooling channel 21, actively cooling the elastic tube 3. The cooling channel 21 is crucial, reducing the fuel temperature from over 1000 degrees Celsius to below 900K, which is within the material's tolerance, and is key to preventing the elastic tube 3 from burning or softening. The main function of the elastic tube 3 is to inject fuel, which is injected into the combustion chamber along the axial direction of the elastic tube. The elastic tube 3 maintains its original shape when there is no external force, can deform under external force, and returns to its original shape after the external force subsides. The ideal deformation direction of the elastic tube 3 is radial. High-speed engine combustion chambers with different operating speed ranges and configurations have very different operating conditions, wall heat flux density, and fuel density variation ranges, requiring adjustment of the elastic modulus of the elastic tube to adapt to different operating environments.

[0025] When the injection device is working, the fuel in the cooling channel of the combustion chamber sidewall cools and absorbs heat from the combustion chamber wall. When the fuel that has not undergone phase change is introduced into the injection channel 31, the elastic tube 3 remains in its original state. When the fuel that has undergone phase change is introduced into the injection channel 31, the elastic tube 3 deforms and the orifice diameter increases.

[0026] Specifically, when unphased fuel is introduced into the injection channel 31, the liquid fuel will be in a relatively low-pressure environment within the injection channel 31, and the orifice diameter of the elastic tube 3 will be small. When the heat flow from the combustion chamber wall heats the fuel to a high-temperature gaseous state, the change in density leads to higher pressure. At this time, the elastic tube 3 adaptively increases its orifice diameter according to the pressure change, thereby avoiding flow restriction.

[0027] Through the above technical solution, the injection device, including a base, a rigid tube, and an elastic tube, can change the orifice size according to the changes in fuel properties under different wall heat flux densities during the operation of the high-speed engine combustion chamber. This ensures that fuel can flow freely or penetrate to insufficient depth at various operating points, guaranteeing that the high-speed engine combustion chamber can operate normally within its operating range. When the high-speed engine is running at low Mach numbers, the original diameter or a small deformation diameter is maintained under the working medium of the gas-liquid two-phase fuel. Figure 1 As shown, this ensures sufficient fuel penetration depth; when operating at high Mach numbers, the fuel becomes a gaseous phase and its density decreases, causing the metal-rubber layer of the injection device to deform and enlarge the injection orifice diameter, as shown. Figure 2 As shown, this avoids fuel flow restriction.

[0028] In this embodiment, the rigid tube 2 is made of fiber-reinforced ceramic matrix composite material with ceramic as the matrix and fiber as the composite.

[0029] Specifically, ceramics possess excellent properties such as high temperature resistance, high strength, high stiffness, relatively light weight, and corrosion resistance. When combined with high-strength, highly elastic fibers, the brittleness of ceramic materials is significantly improved, resulting in fiber-reinforced ceramic matrix composites with excellent toughness. Examples of such fiber-reinforced ceramic matrix composites include silicon carbide ceramic matrix composites.

[0030] Through the above technical solution, the rigid tube body is made of fiber-reinforced ceramic matrix composite material, which has the characteristics of high temperature resistance, high strength, high rigidity, relatively light weight, corrosion resistance and excellent toughness, and is suitable for use as a rigid tube body in injection device.

[0031] In this embodiment, the elastic tube 3 is made of metal-rubber material produced by spiral winding, weaving blanks or stamping.

[0032] Specifically, the metal rubber can withstand extreme temperatures ranging from -80℃ to 1000℃ and corrosive environments, and possesses properties such as radiation resistance and aging resistance. The elastic tube 3 uses metal rubber as the elastic material for deformation. When pressure changes, the deformation of the metal rubber material is tested, and the elastic coefficient of the metal rubber is adjusted to achieve the expected range of change.

[0033] Through the above technical solution, the elastic tube body is made of metal rubber material, which can not only withstand a certain high temperature, but also can be elastically deformed, making it suitable for use as an elastic tube body in injection devices.

[0034] In this embodiment, one end of the elastic tube 3 along the axial direction is connected to the base 1 through a plurality of connection points 11 evenly distributed along the circumference.

[0035] Specifically, if the end of the elastic tube 3 is fully connected to the base 1, the inability to deform at the connection point will result in significant shear stress within the material, which could easily damage the injection channel. The elastic tube 3 is connected to the base through several connection points 11 to prevent significant shear stress within the elastic tube. For example, the end of the elastic tube 3 can be connected through three, four, five, or six connection points 11.

[0036] The above technical solution involves partially connecting the elastic tube to the base, thereby increasing the lifespan of the elastic tube.

[0037] In this embodiment, when the elastic tube 3 is in its original state, its tube wall is spaced a certain distance from the tube wall of the rigid tube 2.

[0038] Specifically, if there is no gap between the elastic tube 3 and the rigid tube 2, the rigid tube 2 will excessively constrain the elastic tube 3, preventing the elastic tube 3 from deforming and causing malfunction. A gap exists between the elastic tube 3 and the rigid tube 2 to prevent the elastic tube 3 from malfunctioning due to excessive constraint from the rigid tube 2 before failure.

[0039] Through the above technical solution, a gap exists between the elastic tube and the rigid tube, ensuring that the elastic tube has room for deformation and can work normally.

[0040] In this embodiment, the tube hole of the rigid tube 2 is frustum-shaped, the small opening of the rigid tube 2 is connected to the base 1, the outer contour of the elastic tube 3 is cylindrical, the outer diameter of the end of the elastic tube 3 connected to the base 1 is equal to the inner diameter of the end of the rigid tube 2 connected to the base 1, and the outer diameter of the end of the elastic tube 3 away from the base 1 is smaller than the inner diameter of the end of the rigid tube 2 away from the base 1.

[0041] Specifically, the rigid tube 2 gradually increases or decreases in diameter along the axial direction of the bore. The elastic tube 3 remains unchanged in outer diameter along the axial direction of the bore. As a result, a gap is formed between the elastic tube 3 and the rigid tube 2, serving as a deformation space for the elastic tube 3.

[0042] With the above technical solution, the tube hole of the rigid tube is frustum-shaped, and the outer contour of the elastic tube is cylindrical. The rigid tube and the elastic tube can be easily connected coaxially, while a gap can be formed between the rigid tube and the elastic tube.

[0043] In this embodiment, the base 1 and the rigid tube 2 are an integral structure.

[0044] Specifically, the base 1 and the rigid tube 2 are not two independent parts, but together form an inseparable whole component, and there is no assembly connection between the two.

[0045] With the above technical solution, the base and the rigid tube are integrated into one structure, which not only meets the performance requirements but also simplifies the subsequent assembly process.

[0046] In this embodiment, the cooling channel on the side wall of the combustion chamber and the cooling channel 21 on the side wall of the rigid tube 2 are integrated channels.

[0047] Specifically, when fuel enters the cooling channels on the side wall of the combustion chamber, it cools the side wall of the combustion chamber and simultaneously enters the cooling channels 21 on the side wall of the rigid tube 2, cooling the rigid tube 2 and consequently the elastic tube 3. The fuel flowing out of the cooling channels of the combustion chamber and the rigid tube 2 is then sent into the injection channel 31.

[0048] With the above technical solution, both the combustion chamber sidewall and the rigid tube sidewall are cooled by fuel, which can improve the combustion performance of subsequent fuel.

[0049] In this embodiment, the cooling channel 21 is a tortuous channel.

[0050] Specifically, the cooling channel 21 is a tortuous and meandering channel. By bending and meandering multiple times, the flow path of the cooling medium is extended, the heat exchange area is increased, the cooling efficiency is improved, and the heat dissipation is made more uniform.

[0051] Through the above technical solution, the cooling channel 21 is a tortuous and meandering channel, which improves heat dissipation efficiency.

[0052] Obviously, the above embodiments are merely illustrative examples for clear explanation and are not intended to limit the implementation. Those skilled in the art will recognize that other variations or modifications can be made based on the above description. It is neither necessary nor possible to exhaustively list all possible implementations here. However, obvious variations or modifications derived therefrom are still within the scope of protection of this invention.

Claims

1. An adaptive adjustment injection device for a high-speed engine combustion chamber, characterized in that, The device includes a base, a rigid tube, and an elastic tube. One end of the rigid tube is connected to the base along the axial direction. The side wall of the rigid tube is provided with a cooling channel. The elastic tube is located inside the rigid tube and one end of the elastic tube is connected to the base along the axial direction. The tube hole of the elastic tube is a spray channel, and the spray channel can adaptively adjust the diameter of the tube hole.

2. The adaptive adjustment injection device according to claim 1, characterized in that, The rigid tube body is made of fiber-reinforced ceramic matrix composite material, which is a composite of ceramic and fiber.

3. The adaptive adjustment injection device according to claim 1, characterized in that, The elastic tube is made of metal-rubber material produced by spiral winding, braiding blanks, or stamping.

4. The adaptive adjustment injection device according to claim 1, characterized in that, One end of the elastic tube along the axial direction is connected to the base through a plurality of connection points evenly distributed along the circumference.

5. The adaptive adjustment injection device according to claim 1, characterized in that, When the elastic tube is in its original state, its wall is spaced a certain distance from the wall of the rigid tube.

6. The adaptive adjustment injection device according to claim 5, characterized in that, The rigid tube has a frustum-shaped bore, and the small opening of the rigid tube is connected to the base. The elastic tube has a cylindrical outer contour. The outer diameter of the end of the elastic tube connected to the base is equal to the inner diameter of the end of the rigid tube connected to the base. The outer diameter of the end of the elastic tube away from the base is smaller than the inner diameter of the end of the rigid tube away from the base.

7. The adaptive adjustment injection device according to claim 1, characterized in that, The base and the rigid tube are an integral structure.

8. The adaptive adjustment injection device according to claim 1, characterized in that, The cooling channels on the side wall of the combustion chamber and the cooling channels on the side wall of the rigid tube are integrated channels.

9. The adaptive adjustment injection device according to claim 1, characterized in that, The cooling channel is a tortuous and meandering channel.

10. An adaptive injection adjustment method for a high-speed engine combustion chamber, characterized in that, Using any one of the adaptive adjustment injection devices according to claims 1 to 9, the fuel in the cooling channel of the combustion chamber sidewall cools and absorbs heat from the combustion chamber wall. When fuel that has not undergone phase change is introduced into the injection channel, the elastic tube remains in its original state. When fuel that has undergone phase change is introduced into the injection channel, the elastic tube deforms and its orifice diameter increases.

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