Liquid motor thrust chamber throat neck assembly, method of manufacture and method of operation thereof

Abstract

The application discloses a liquid engine thrust chamber throat neck assembly, a manufacturing method and a working method thereof, and belongs to the field of liquid engine thrust chamber heat dissipation, and comprises a throat conformal cooling flow channel and a phase change heat absorption unit which are integrally printed in the throat region of the thrust chamber lining through SLM (selective laser melting), the phase change heat absorption unit and the throat conformal cooling flow channel are alternately and spacedly arranged along the circumferential direction of the thrust chamber lining, after the throat lining absorbs the peak heat flow generated by the gas, the heat flow is transmitted in two ways, one way is directly conducted to the throat conformal cooling flow channel through the metal base, and the other way is introduced into the phase change heat absorption unit and then dispersed by phase change of the working medium. By using the liquid engine thrust chamber throat neck assembly, the manufacturing method and the working method thereof, the phase change is used to strengthen the heat dissipation capacity of the throat, the effective heat exchange area is greatly improved, the wall peak temperature is reduced, and the working reliability and the service life of the thrust chamber are improved.

Description

Technical Field

[0001] This invention relates to the field of heat dissipation technology for the thrust chamber of a liquid engine, and in particular to a throat assembly for the thrust chamber of a liquid engine, its manufacturing method, and its operating method. Background Technology

[0002] The body and throat of the liquid rocket engine thrust chamber are the core and critical components with the highest thermal load of the entire engine. The gas flow cross-section at the throat is sharply constricted, and both the gas velocity and the wall heat flux density reach their peak values ​​throughout the entire section. Under the long-term exposure to extreme high-temperature thermal environments, the components are highly susceptible to failure defects such as internal wall ablation, high-temperature thermal deformation, and cyclic thermal fatigue cracking, which seriously restricts the continuous operating time and operational reliability of the liquid rocket engine.

[0003] Currently, mainstream thrust chamber cooling solutions in the industry generally adopt a single sandwich-type cooling channel structure, relying on forced convection heat transfer of the propellant cooling medium to achieve heat dissipation from the wall. Due to the inherent spatial constraints of the narrow throat region, the effective heat exchange area available for traditional cooling structures is extremely limited. Even if the cooling capacity is improved by increasing the cooling medium flow rate and optimizing the channel cross-section and arrangement, it is still difficult to match the heat dissipation requirements of the peak heat load in the throat region. Summary of the Invention

[0004] The purpose of this invention is to provide a throat assembly for a liquid engine thrust chamber, its manufacturing method, and its operating method, thereby solving the aforementioned technical problems.

[0005] To achieve the above objectives, the present invention provides a throat assembly for a liquid engine thrust chamber, comprising a throat conformal cooling channel and a phase change heat absorption unit integrally formed in the throat region of the thrust chamber liner by selective laser melting (SLM). The phase change heat absorption unit and the throat conformal cooling channel are arranged alternately along the circumferential direction of the thrust chamber liner. After absorbing the peak heat flow generated by the combustion gas, the throat liner transmits it in two paths. One path is directly conducted to the throat conformal cooling channel through the metal substrate, and the other path is introduced into the interior of the phase change heat absorption unit to disperse the heat by the phase change of the working fluid. The phase change heat absorption unit then conducts the accumulated heat to the adjacent throat conformal cooling channel through the solid metal outer wall. Finally, the propellant flowing through the throat conformal cooling channel carries away all the heat in a unified manner through forced convection.

[0006] Preferably, the phase change heat absorption unit has a hollow cavity structure, and the inner end of the phase change heat absorption unit contacts the throat region of the thrust chamber liner to form an evaporation wall. The two sides of the evaporation wall extend radially outward from the center of the thrust chamber liner to form an extension wall. The outer end of the phase change heat absorption unit is integrally formed with the extension wall to form a condensation wall. Both the inner walls of the evaporation wall and the extension wall are integrally formed with a three-dimensional porous mesh, which is used to wet and store the liquid phase change working fluid and drive the condensed liquid working fluid to flow back to the evaporation wall by relying on capillary negative pressure. The hollow channel formed by the three-dimensional porous mesh on the inner wall of the evaporation wall and the extension wall is a gas phase channel, which is used to transport the vaporized gas phase working fluid radially from the inner evaporation wall to the outer condensation wall. The condenser wall is a metal outer wall surface used for heat exchange with the conformal cooling channel in the throat.

[0007] Preferably, both ends of the hollow channel of all phase change heat absorption units are connected to the annular channel. The annular channel is sealed by welding and has a filling port, which is used to equalize the pressure of the gas phase and liquid phase working fluid inside the cavity of all phase change heat absorption units. The phase change working fluid of all phase change heat absorption units can be uniformly filled through a single filling port.

[0008] Preferably, the thrust chamber liner area also has an integrally formed body conformal cooling channel, and the body conformal cooling channel and the throat conformal cooling channel are a single continuous through structure, with the cooling propellant flowing from top to bottom through the body conformal cooling channel and the throat conformal cooling channel.

[0009] Preferably, the thrust chamber liner, the throat conformal cooling channel, the body conformal cooling channel, the three-dimensional porous mesh, and the annular channel are all made of copper alloy.

[0010] Preferably, the cross-sectional dimensions of the conformal cooling channel in the throat and the conformal cooling channel in the body are 1.5mm-4mm.

[0011] A method for manufacturing a throat neck assembly for a liquid engine thrust chamber includes the following steps: S1. Construct an integrated 3D model including the thrust chamber liner, body conformal cooling channel, throat conformal cooling channel, phase change heat absorption unit, three-dimensional porous mesh, annular channel and heat pipe phase change working fluid injection port, and complete SLM printing slicing processing and laser scanning manufacturing path planning. S2. Copper alloy powder is selected as the printing material, and the component is integrally formed using SLM selective laser melting technology. The thrust chamber liner, body conformal cooling channel, throat conformal cooling channel, phase change heat absorption unit solid outer wall, and annular channel are processed using the first set of forming process parameters: spot size 0.03mm-0.06mm, layer thickness 0.04mm-0.06mm, laser power 450W-550W, scanning speed 500mm / s-1100mm / s, and melt channel distance 0.06mm-0.11mm. The three-dimensional porous mesh is processed using differentiated second set of forming process parameters: spot size 0.03mm-0.06mm, layer thickness 0.04mm-0.06mm, laser power 350W-500W, scanning speed 600mm / s-1300mm / s, and melt channel distance 0.08mm-0.13mm. S3. Perform internal cavity cleaning treatment on the integrated component after SLM molding: remove residual metal powder from the cooling channel, the hollow cavity of the phase change heat absorption unit, and the three-dimensional porous mesh. Then, carry out stress relief heat treatment to eliminate residual printing stress, and finally perform surface finishing. S4. Liquid heat pipe phase change working fluid is uniformly injected into all interconnected phase change heat absorption units through the injection port on the annular channel. S5. The filling port is sealed by argon arc welding. After welding, the air tightness of the entire component is tested. If it passes the test, the finished liquid engine thrust chamber throat neck assembly is obtained.

[0012] A method for operating a thrust chamber throat neck assembly of a liquid engine includes the following steps: When the engine is running, fuel and oxidizer mix and burn in the inner cavity of the thrust chamber liner to generate high-temperature gas. The high-temperature gas flows through the body area and throat area of ​​the thrust chamber liner in sequence. The throat area forms a peak heat flow of the gas due to the contraction of the flow cross section. The heat is first absorbed by the integrated thrust chamber liner matrix. During this process, cryogenic propellant is continuously fed into the continuous and interconnected body conformal cooling channel and throat conformal cooling channel from top to bottom. It first flows through the body conformal cooling channel and removes the basic combustion heat of the thrust chamber body area through forced convection heat transfer, thereby achieving conventional heat dissipation of the tube section substrate. The propellant continues to flow downwards into the conformal cooling channel in the throat, directly dissipating heat from the throat liner substrate via convection. Simultaneously, the peak heat flow concentrated in the throat region is introduced into the circumferentially alternating phase change heat absorption units. The liquid phase change working fluid, wetted by the three-dimensional porous mesh on the inner evaporation wall and extension wall of the phase change heat absorption unit, absorbs heat and vaporizes. It absorbs the locally concentrated high heat flow in the throat through the latent heat of phase change, eliminating hot spots on the wall surface. The vaporized gaseous working fluid is transported radially from the inner evaporation wall to the outer condensation wall through the central gaseous channel formed by the three-dimensional porous mesh. The gaseous working fluid releases the latent heat of phase change and liquefies at the condensation wall, transferring the accumulated peak heat through the metal solid of the condensation wall to the adjacent conformal cooling channel in the throat. The liquefied phase change working fluid relies on the capillary negative pressure generated by the capillary pores of the three-dimensional porous mesh to flow radially back from the outer condensation area to the inner evaporation wall area, achieving gravity-free, all-attitude working fluid circulation.

[0013] Therefore, the present invention, employing the above-mentioned liquid engine thrust chamber throat neck assembly, manufacturing method, and operating method, has the following beneficial effects: 1. This invention adopts a dual-path composite heat dissipation structure of "direct heat conduction of the substrate + phase change heat transfer of the phase change unit", which breaks through the heat dissipation limit of the traditional single regenerative cooling method. It addresses the technical pain points of the throat flow section shrinkage, heat flux density concentration and easy ablation. The phase change heat absorption unit uses the latent heat of the working fluid phase change to quickly absorb and transfer the local peak heat flux. Combined with the propellant forced convection heat dissipation of the conformal cooling channel in the throat, it significantly reduces the peak temperature of the throat wall, effectively eliminates local high temperature hot spots, and inhibits failure problems such as throat ablation and hot cracking. It significantly improves the high-temperature operating reliability and service life of the thrust chamber throat area. 2. This invention achieves two-phase flow separation of gas and liquid by integrating a three-dimensional porous mesh and an independent gas phase channel within the phase change heat absorption unit: the gas phase working fluid is rapidly transported radially through the central hollow channel, while the liquid phase working fluid is stably refluxed by the capillary negative pressure of the mesh. The two phase flows do not interfere with each other, greatly reducing the heat pipe heat exchange resistance and improving the phase change cycle efficiency. At the same time, the capillary-driven reflux method breaks away from the limitations of traditional gravity reflux, and can be adapted to complex conditions such as weightlessness, variable overload, and multi-attitude maneuvering during rocket flight, ensuring the stable operation of the throat and neck cooling system throughout the process without the risk of dry evaporation failure. 3. In this invention, all phase change heat absorption units are connected as a whole through an annular channel, which can realize the unified injection of phase change working fluid at a single port, simplify the assembly and sealing process, reduce the risk of leakage from multiple sealing ports, and at the same time, it can balance the gas and liquid phase pressures inside all phase change heat absorption units, making the heat exchange performance of the throat uniform and consistent throughout the circumference, avoiding the problem of uneven local heat exchange and local overheating, and greatly improving the consistency and stability of the overall circumferential heat dissipation. 4. This invention adopts SLM selective laser melting integrated forming process to integrally form the thrust chamber liner, continuous conformal cooling channel, phase change heat absorption cavity, three-dimensional porous capillary mesh and annular channel in metallurgical form. There are no splices, no welds and no assembly gaps, which completely eliminates the contact thermal resistance of traditional split assembly structure and the heat transfer efficiency is higher. At the same time, the solid structure and porous mesh are formed by different laser process parameters. Under the premise of ensuring the overall structural strength and pressure bearing capacity, the capillary liquid storage and reflux performance requirements are precisely matched, taking into account the structural reliability and heat dissipation performance. 5. The conformal cooling channels in the body and throat of this invention are continuously connected vertically, resulting in a smooth propellant cooling circuit with low resistance. This allows for the sequential completion of basic heat dissipation in the body and peak heat dissipation in the throat, leading to a more rational distribution of cooling heat exchange. At the same time, the overall structure is formed using homogeneous copper alloy material, ensuring consistent thermal expansion performance under alternating hot and cold conditions. This prevents defects such as delamination, cracking, and detachment, resulting in excellent structural thermal stability. 6. This invention arranges the phase change heat absorption unit and the throat cooling channel alternately in the circumferential direction, without occupying additional external space of the throat neck, and without increasing the overall size and weight of the components, which meets the lightweight and compact design requirements of liquid rocket engines; at the same time, by sharing the peak heat load through the phase change unit, the dependence on propellant flow rate and pump pressure supply is effectively reduced, and the design difficulty of the engine fluid supply system and the overall load are reduced.

[0014] The technical solution of the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. Attached Figure Description

[0015] Figure 1 This is a schematic diagram of the principle of a thrust chamber throat assembly for a liquid engine according to the present invention; Figure 2 This is a schematic diagram of the flow channel structure of the throat assembly of a liquid engine thrust chamber according to the present invention; Figure 3 This is a diagram showing the arrangement of a phase change heat absorption unit in the throat assembly of a liquid engine thrust chamber according to the present invention. Figure 4 This is a three-dimensional outline of a thrust chamber throat assembly for a liquid engine according to the present invention.

[0016] Figure Labels 1. Thrust chamber liner; 2. Throat conformal cooling channel; 3. Phase change heat absorption unit; 31. Extended wall; 32. Three-dimensional porous mesh; 33. Gas phase channel; 34. Annular channel; 35. Filling port; 4. Body conformal cooling channel; 5. Throat region; 6. Body region. Detailed Implementation

[0017] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the embodiments of the present invention will be further described in detail below with reference to the accompanying drawings and examples. It should be understood that the specific embodiments described herein are merely illustrative of the embodiments of the present invention and are not intended to limit the embodiments of the present invention. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the scope of protection of this application. Examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout.

[0018] It should be noted that the terms "comprising" and "having," and any variations thereof, are intended to cover non-exclusive inclusion, such as a process, method, system, product, or server that includes a series of steps or units, not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such process, method, product, or device.

[0019] The embodiments of the present invention will now be described in detail with reference to the accompanying drawings.

[0020] like Figures 1-4 As shown, a throat assembly for a liquid engine thrust chamber includes a throat conformal cooling channel 2 and a phase change heat absorption unit 3 integrally printed in the throat region 5 of the thrust chamber liner 1 by selective laser melting (SLM). The phase change heat absorption unit 3 and the throat conformal cooling channel 2 are arranged alternately along the circumference of the thrust chamber liner 1. After the throat liner absorbs the peak heat flow generated by the combustion gas, it is transferred in two ways. One way is directly conducted to the throat conformal cooling channel 2 through the metal substrate, and the other way is introduced into the interior of the phase change heat absorption unit 3 to disperse the heat by the phase change of the working fluid. The phase change heat absorption unit 3 then conducts the accumulated heat to the adjacent throat conformal cooling channel 2 through the solid metal outer wall surface. Finally, the propellant flowing through the throat conformal cooling channel 2 carries away all the heat in a unified manner in the form of forced convection.

[0021] The phase change heat absorption unit 3 has a hollow cavity structure, and the inner end of the phase change heat absorption unit 3 contacts the throat region 5 of the thrust chamber liner 1 to form an evaporation wall. The two sides of the evaporation wall extend radially outward from the center of the thrust chamber liner 1 to form an extension wall 31. The outer end of the phase change heat absorption unit 3 is integrally formed with the extension wall 31 to form a condensation wall. The inner walls of the evaporation wall and the extension wall 31 are integrally formed with a three-dimensional porous mesh 32, which is used to wet and store the liquid phase change working fluid and drive the condensed liquid working fluid to flow back to the evaporation wall by relying on capillary negative pressure. The hollow channel formed by the three-dimensional porous mesh 32 on the inner walls of the evaporation wall and the extension wall 31 is a gas phase channel 33, which is used to transport the vaporized gas phase working fluid radially from the inner evaporation wall to the outer condensation wall. The condensation wall is a metal outer wall surface, which is used to exchange heat with the throat conformal cooling channel 2.

[0022] Both ends of the hollow channel of all phase change heat absorption units 3 are connected to the annular channel 34. The annular channel 34 is sealed by welding with a filling port 35, which is used to equalize the pressure of the gas phase and liquid phase working fluid inside the cavity of all phase change heat absorption units 3, and the phase change working fluid of all phase change heat absorption units 3 can be uniformly filled through a single filling port 35.

[0023] The thrust chamber liner 1 body area 6 is also integrally formed with a body conformal cooling channel 4. The body conformal cooling channel 4 and the throat conformal cooling channel 2 are a single continuous through structure. The cooling propellant flows from top to bottom through the body conformal cooling channel 4 and the throat conformal cooling channel 2.

[0024] The thrust chamber liner 1, the throat conformal cooling channel 2, the body conformal cooling channel 4, the three-dimensional porous mesh 32, and the annular channel 34 are all made of copper alloy. In this embodiment, zirconium copper alloy may be used.

[0025] The cross-sectional dimensions of the conformal cooling channel 2 in the throat and the conformal cooling channel 4 in the body are 1.5mm-4mm. Further cross-sectional dimensions are 2mm-3mm. For example, cross-sectional dimensions of 2.5mm*2.5mm or 1.5mm*3mm can be selected.

[0026] A method for manufacturing a throat neck assembly for a liquid engine thrust chamber includes the following steps: S1. Construct an integrated 3D model including the thrust chamber liner 1, body conformal cooling channel 4, throat conformal cooling channel 2, phase change heat absorption unit 3, three-dimensional porous mesh 32, annular channel 34 and heat pipe phase change working fluid injection port 35, and complete SLM printing slicing processing and laser scanning manufacturing path planning.

[0027] S2. Copper alloy powder is selected as the printing material, and the component is integrally formed using SLM selective laser melting technology. Among them, the thrust chamber liner 1, the body conformal cooling channel 4, the throat conformal cooling channel 2, the phase change heat absorption unit 3 solid outer wall, and the annular channel 34 are processed using the first set of forming process parameters: spot size 0.03mm-0.06mm, layer thickness 0.04mm-0.06mm, laser power 450W-550W, scanning speed 500mm / s-1100mm / s, and melt channel distance 0.06mm-0.11mm; the three-dimensional porous mesh 32 is processed using the differentiated second set of forming process parameters: spot size 0.03mm-0.06mm, layer thickness 0.04mm-0.06mm, laser power 350W-500W, scanning speed 600mm / s-1300mm / s, and melt channel distance 0.08mm-0.13mm.

[0028] Further optional first-stage forming process parameters are: spot size 0.06mm, layer thickness 0.06mm, laser power 550W, scanning speed 900mm / s, and melt channel distance 0.10mm.

[0029] The second forming process parameters are: spot size 0.06mm, layer thickness 0.06mm, laser power 400W, scanning speed 1100mm / s, and melt channel distance 0.13mm.

[0030] S3. Perform internal cavity cleaning treatment on the integrated component after SLM molding: remove residual metal powder from the cooling channel, the hollow cavity of the phase change heat absorption unit 3, and the three-dimensional porous mesh 32. Then carry out stress relief heat treatment to eliminate residual printing stress, and finally perform surface finishing.

[0031] S4. Liquid heat pipe phase change working fluid is uniformly injected into all interconnected phase change heat absorption units 3 through the injection port 35 on the annular channel 34.

[0032] S5. Argon arc welding is used to seal the filling port 35. After welding, the air tightness test is carried out on the entire component. After passing the test, the finished liquid engine thrust chamber throat neck assembly is obtained.

[0033] A method for operating a thrust chamber throat neck assembly of a liquid engine includes the following steps: When the engine is working, the fuel and oxidant mix and burn in the inner cavity of the thrust chamber liner 1 to generate high-temperature gas. The high-temperature gas flows through the body region 6 and throat region 5 of the thrust chamber liner 1 in sequence. The throat region 5 forms a peak heat flow of the gas due to the contraction of the flow cross section. The heat is first absorbed by the integrated thrust chamber liner 1 matrix.

[0034] During this process, cryogenic propellant is continuously fed into the continuous, interconnected body conformal cooling channel 4 and throat conformal cooling channel 2 from top to bottom. It first flows through the body conformal cooling channel 4 and carries away the basic combustion heat of the thrust chamber body region 6 through forced convection heat transfer, thereby achieving conventional heat dissipation of the tube section substrate.

[0035] The propellant continues to flow downwards into the throat conformal cooling channel 2, directly convectively dissipating heat from the throat liner substrate. Simultaneously, the peak heat flow concentrated in the throat region 5 is introduced into the circumferentially alternating phase change heat absorption units 3. The liquid phase change working fluid, wetted by the three-dimensional porous mesh 32 on the inner evaporation wall and extension wall 31 of the phase change heat absorption unit 3, absorbs heat and vaporizes. It absorbs the locally concentrated high heat flow in the throat through the latent heat of phase change, eliminating hot spots on the wall surface. The vaporized gaseous working fluid is transported radially from the inner evaporation wall to the outer condensation wall through the central gaseous channel 33 formed by the three-dimensional porous mesh 32. The gaseous working fluid releases the latent heat of phase change and liquefies at the condensation wall, transferring the accumulated peak heat through the metal solid of the condensation wall to the adjacent throat conformal cooling channel 2. The liquefied phase change working fluid relies on the capillary negative pressure generated by the capillary pores of the three-dimensional porous mesh 32 to flow radially back from the outer condensation area to the inner evaporation wall area, achieving gravity-free, all-attitude working fluid circulation.

[0036] All phase change heat absorption units 3 are balanced by the annular channel 34 to ensure that the heat exchange conditions of each phase change heat absorption unit 3 are consistent throughout the week and there is no local heat exchange failure. Finally, the heat directly conducted in the throat region 5 and the heat transferred by phase change are carried away by the propellant through forced convection in the throat conformal cooling channel 2, thus completing the continuous composite heat dissipation cycle of the entire thrust chamber throat and neck assembly.

[0037] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit them. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can still be made to the technical solutions of the present invention, and these modifications or equivalent substitutions cannot cause the modified technical solutions to deviate from the spirit and scope of the technical solutions of the present invention.

Claims

1. A throat assembly for a thrust chamber of a liquid engine, characterized in that: The system includes a throat conformal cooling channel and a phase change heat absorption unit, which are integrally printed into the throat region of the thrust inner liner using selective laser melting (SLM). The phase change heat absorption unit and the throat conformal cooling channel are arranged alternately along the circumference of the thrust inner liner. After absorbing the peak heat flow generated by the combustion gas, the throat liner transmits the heat in two ways. One way is directly conducted to the throat conformal cooling channel through the metal substrate, and the other way is introduced into the interior of the phase change heat absorption unit to disperse the heat through the phase change of the working fluid. The phase change heat absorption unit then conducts the accumulated heat to the adjacent throat conformal cooling channel through the solid metal outer wall. Finally, the propellant flowing through the throat conformal cooling channel carries away all the heat in a unified manner through forced convection.

2. The throat assembly of a liquid engine thrust chamber according to claim 1, characterized in that: The phase change heat absorption unit has a hollow cavity structure, and the inner end of the phase change heat absorption unit contacts the throat area of ​​the thrust chamber liner to form an evaporation wall. The two sides of the evaporation wall extend radially outward from the center of the thrust chamber liner to form an extension wall. The outer end of the phase change heat absorption unit is integrally formed with the extension wall to form a condensation wall. Both the inner walls of the evaporation wall and the extension wall are integrally formed with a three-dimensional porous mesh, which is used to wet and store the liquid phase change working fluid and drive the condensed liquid working fluid to flow back to the evaporation wall by relying on capillary negative pressure. The hollow channel formed by the three-dimensional porous mesh on the inner wall of the evaporation wall and the extension wall is a gas phase channel, which is used to transport the vaporized gas phase working fluid radially from the inner evaporation wall to the outer condensation wall. The condenser wall is a metal outer wall surface used for heat exchange with the conformal cooling channel in the throat.

3. The throat assembly of a liquid engine thrust chamber according to claim 2, characterized in that: Both ends of the hollow channel of all phase change heat absorption units are connected to the annular channel. The annular channel is sealed by welding and has a filling port, which is used to equalize the pressure of the gas phase and liquid phase working fluid inside the cavity of all phase change heat absorption units. The phase change working fluid of all phase change heat absorption units can be uniformly filled through a single filling port.

4. The throat assembly of a liquid engine thrust chamber according to claim 3, characterized in that: The thrust chamber liner area also has an integrally formed body conformal cooling channel. The body conformal cooling channel and the throat conformal cooling channel are a single continuous through structure. The cooling propellant flows from top to bottom through the body conformal cooling channel and the throat conformal cooling channel.

5. The throat assembly of a liquid engine thrust chamber according to claim 4, characterized in that: The thrust chamber liner, throat conformal cooling channel, body conformal cooling channel, three-dimensional porous mesh, and annular channel are all made of copper alloy.

6. A thrust chamber throat assembly for a liquid engine according to claim 4 or 5, characterized in that: The cross-sectional dimensions of the conformal cooling channels in the throat and body are 1.5mm-4mm.

7. A method for manufacturing a thrust chamber throat assembly for a liquid engine as described in claim 6, characterized in that: Includes the following steps: S1. Construct an integrated 3D model including the thrust chamber liner, body conformal cooling channel, throat conformal cooling channel, phase change heat absorption unit, three-dimensional porous mesh, annular channel and heat pipe phase change working fluid injection port, and complete SLM printing slicing processing and laser scanning manufacturing path planning. S2. Copper alloy powder is selected as the printing material, and the component is integrally formed using SLM selective laser melting technology. The thrust chamber liner, body conformal cooling channel, throat conformal cooling channel, phase change heat absorption unit solid outer wall, and annular channel are processed using the first set of forming process parameters: spot size 0.03mm-0.06mm, layer thickness 0.04mm-0.06mm, laser power 450W-550W, scanning speed 500mm / s-1100mm / s, and melt channel distance 0.06mm-0.11mm. The three-dimensional porous mesh is processed using differentiated second set of forming process parameters: spot size 0.03mm-0.06mm, layer thickness 0.04mm-0.06mm, laser power 350W-500W, scanning speed 600mm / s-1300mm / s, and melt channel distance 0.08mm-0.13mm. S3. Perform internal cavity cleaning treatment on the integrated component after SLM molding: remove residual metal powder from the cooling channel, the hollow cavity of the phase change heat absorption unit, and the three-dimensional porous mesh. Then, carry out stress relief heat treatment to eliminate residual printing stress, and finally perform surface finishing. S4. Liquid heat pipe phase change working fluid is uniformly injected into all interconnected phase change heat absorption units through the injection port on the annular channel. S5. The filling port is sealed by argon arc welding. After welding, the air tightness of the entire component is tested. If it passes the test, the finished liquid engine thrust chamber throat neck assembly is obtained.

8. The method of operating a thrust chamber throat assembly of a liquid engine as described in claim 6, characterized in that: Includes the following steps: When the engine is running, fuel and oxidizer mix and burn in the inner cavity of the thrust chamber liner to generate high-temperature gas. The high-temperature gas flows through the body area and throat area of ​​the thrust chamber liner in sequence. The throat area forms a peak heat flow of the gas due to the contraction of the flow cross section. The heat is first absorbed by the integrated thrust chamber liner matrix. During this process, cryogenic propellant is continuously fed into the continuous and interconnected body conformal cooling channel and throat conformal cooling channel from top to bottom. It first flows through the body conformal cooling channel and removes the basic combustion heat of the thrust chamber body area through forced convection heat transfer, thereby achieving conventional heat dissipation of the tube section substrate. The propellant continues to flow downwards into the conformal cooling channel in the throat, directly dissipating heat from the throat liner substrate via convection. Simultaneously, the peak heat flow concentrated in the throat region is introduced into the circumferentially alternating phase change heat absorption units. The liquid phase change working fluid, wetted by the three-dimensional porous mesh on the inner evaporation wall and extension wall of the phase change heat absorption unit, absorbs heat and vaporizes. It absorbs the locally concentrated high heat flow in the throat through the latent heat of phase change, eliminating hot spots on the wall surface. The vaporized gaseous working fluid is transported radially from the inner evaporation wall to the outer condensation wall through the central gaseous channel formed by the three-dimensional porous mesh. The gaseous working fluid releases the latent heat of phase change and liquefies at the condensation wall, transferring the accumulated peak heat through the metal solid of the condensation wall to the adjacent conformal cooling channel in the throat. The liquefied phase change working fluid relies on the capillary negative pressure generated by the capillary pores of the three-dimensional porous mesh to flow radially back from the outer condensation area to the inner evaporation wall area, achieving gravity-free, all-attitude working fluid circulation.

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