Thermal matching optimization method for U-shaped component of high-temperature spray pipe

Abstract

The invention provides a thermal matching optimization method for a U-shaped component of a high-temperature spray pipe, and the method comprises the steps: constructing parameterized models of the U-shaped component of the spray pipe and a typical TPS structure which is the same as a thermal protection structure of the U-shaped component of the spray pipe, the typical TPS structure is a multi-layer material composite structure which at least comprises a heat-proof layer on the outermost side and a heat-insulating layer located on the inner side of the heat-proof layer. Based on the parameterized model of the typical TPS structure, taking the thickness of each layer as a variable, taking the total thickness of the TPS and the temperature of a heat insulation layer as constraints, and taking the minimum weight of the typical TPS structure as a target, carrying out heat transfer design of the typical TPS structure to obtain an optimal thickness ratio of each layer; the optimal thickness ratio of each layer of a typical TPS structure is applied to a parameterized model of the U-shaped component of the spray pipe, and the optimal thickness ratio of each layer of the typical TPS structure is obtained by taking the bolt size and the bolt hole gap for connecting the bolts of each layer as variables, taking the stress and the nail load of each layer of the U-shaped component of the spray pipe as constraints and taking the minimum bolt hole gap as a target. And carrying out thermal matching optimization design on the U-shaped component of the spray pipe to obtain an optimal bolt size and an optimal bolt hole gap.

Description

Technical Field

[0001] The present application belongs to the field of aircraft structure thermal protection design, and in particular relates to a method for optimizing thermal matching of a high-temperature nozzle U-shaped component. Background Art

[0002] With the development of aerospace equipment, the core flow temperature of the nozzle in the ramjet state is as high as thousands of degrees Celsius. Under the extreme environmental conditions in the nozzle area, it is necessary to carry out thermal protection structure (TPS) design involving multiple disciplines such as aerodynamics, thermal management, materials, and structural strength. The existing thermal protection structure design is difficult to meet the development needs of new aircraft. Thermal problems have become one of the key constraints and major technical bottlenecks in the development of new aircraft.

[0003] At present, the optimization design methods for normal temperature structures at home and abroad are relatively mature, and it is not difficult to design a lightweight, high-load-bearing structure. At the same time, with the development of various new high-temperature resistant structural materials and high-efficiency heat-proof materials, conditions have been created for the development of new thermal protection systems that can resist high temperature / high-load extreme conditions; however, under the extreme environmental conditions in the nozzle area, simple material design and structural design are far from enough and it is difficult to meet the nozzle design requirements. Summary of the invention

[0004] The purpose of the present application is to provide a method for optimizing thermal matching of a high-temperature nozzle U-shaped component to solve or alleviate at least one problem in the background technology.

[0005] The technical solution of the present application is: a method for optimizing thermal matching of a high-temperature nozzle U-shaped component, comprising:

[0006] Step S100, constructing a parameterized model of a nozzle U-shaped component and a typical TPS structure, wherein the typical TPS structure is the same as the thermal protection structure of the nozzle U-shaped component, and the typical TPS structure is a multi-layer material composite structure consisting of at least an outermost heat protection layer and a heat insulation layer located inside the heat protection layer;

[0007] Step S200, based on the parameterized model of the typical TPS structure, taking the thickness of each layer as a variable, taking the total thickness of the TPS and the temperature of the insulation layer as constraints, and taking the minimum weight of the typical TPS structure as the goal, a typical TPS structure heat transfer optimization design is carried out to obtain the optimal thickness ratio of each layer of the typical TPS structure;

[0008] Step S300, applying the optimal thickness ratio of each layer of the typical TPS structure to the parametric model of the nozzle U-shaped component, taking the bolt size and bolt hole gap of the bolts connecting each layer as variables, taking the stress and nail load of each layer of the nozzle U-shaped component as constraints, and taking the minimum bolt hole gap as the goal, the nozzle U-shaped component thermal matching optimization design is carried out to obtain the optimal bolt size and bolt hole gap of the nozzle U-shaped component.

[0009] In an optional embodiment of the present application, the parameterized model of the nozzle U-shaped component and the typical TPS structure is established by Abaqus software.

[0010] In an optional implementation manner of the present application, the process of establishing a typical TPS structural parameterized model by Abaqus software is as follows:

[0011] First, a parametric model of a typical TPS structure is established;

[0012] Using the Transfer analysis step, a thermal environment temperature of T is applied to the upper surface of the heat protection layer. E , radiation boundary conditions with a radiation coefficient of η1, and an ambient temperature of T is applied to the lower surface and surrounding of the insulation layer. k , the heat dissipation radiation boundary condition with a radiation coefficient of η2, the contact thermal resistance R1 is set between the two adjacent layers, the equivalent thermal conductivity is ζ, the heating is a transient process, and the time is t1, thereby completing the parametric modeling of the typical TPS structure.

[0013] In an optional embodiment of the present application, the process of carrying out heat transfer design of a typical TPS structure to obtain the optimal thickness ratio of each layer of the typical TPS structure is as follows:

[0014] Determine the thickness variables of each layer of the typical TPS structure and the thickness variation range of each layer, so that the thickness variables of each layer of the typical TPS structure are within the thickness variation range of each layer, and set the minimum iteration step size;

[0015] Determine the thermal insulation layer temperature constraint, including the thermal insulation layer material temperature allowable value and the innermost thermal insulation layer backside temperature maximum value, so that the thermal insulation layer temperature is less than the thermal insulation layer material temperature allowable value, and the innermost thermal insulation layer backside temperature is less than the innermost thermal insulation layer backside temperature maximum value;

[0016] Determine the total thickness of the TPS structure so that the sum of the thicknesses of each layer is less than the total thickness of the TPS structure;

[0017] With the goal of minimizing the total weight of the TPS structure, heat transfer optimization is performed to achieve the optimal thickness ratio of each layer of the typical TPS structure.

[0018] In an optional embodiment of the present application, a heat transfer optimization calculation of a typical TPS structure is performed based on Optimus software, and the process includes:

[0019] Firstly, parameter sensitivity analysis is performed to obtain the corresponding relationship between the response parameters including the total thickness of TPS, the temperature of the thermal insulation layer, the total weight of the structure and the variable parameters of the thickness of each layer in the design space;

[0020] Then, the system response surface model is obtained by interpolation method to analyze the influence of response parameters and variable parameters;

[0021] Finally, multi-objective optimization was performed based on the system response surface model to obtain the optimal thickness ratio of each layer of the TPS structure.

[0022] In an optional implementation of the present application, the response parameters of the total TPS thickness, the temperature of the insulation layer and the total weight of the structure are stored by a Python script, so that the Optimus software can retrieve the text content for iterative optimization.

[0023] In an optional embodiment of the present application, the process of establishing a parametric model of the nozzle U-shaped component by using Abaqus software is as follows:

[0024] Firstly, a finite element model for heat transfer analysis of the nozzle U-shaped component is established, which includes the heat protection layer, the heat insulation layer and the metal outer load-bearing skin from the inside to the outside.

[0025] The Transfer analysis step is used to set the initial temperature of the nozzle U-shaped component to T. The interior of the nozzle U-shaped component is divided into three temperature zones according to the actual working conditions. Thermal radiation boundary conditions with a radiation coefficient of η1 are applied to the outer surface of the heat protection layer in the three temperature zones. The ambient temperature of T is applied to the outermost layer of the metal outer load-bearing skin. k , the heat dissipation radiation boundary condition of the radiation coefficient η2, the contact thermal resistance is set between each layer, the equivalent thermal conductivity is ζ, the heating is a transient process, the time is t1, and the establishment of the finite element model of heat transfer analysis is completed;

[0026] Based on the heat transfer analysis finite element model, Fasteners connection units are introduced to simulate the bolt connection between layers, and the bolt size and bolt hole gap are set by modifying the Fasteners unit properties;

[0027] The Static analysis step is adopted, and the temperature boundary uses the heat transfer analysis results to map the temperature field. At the same time, the simply supported boundary condition is applied to the outermost layer, and the aerodynamic pressure load is applied to the inner layer, thereby completing the establishment of the parametric model of the nozzle U-shaped component for thermal-mechanical coupling calculation.

[0028] In an optional embodiment of the present application, the process of carrying out the thermal matching optimization design of the nozzle U-shaped component to obtain the optimal bolt size and bolt hole clearance of the nozzle U-shaped component is:

[0029] Determine the bolt size and bolt hole clearance variables and the bolt size and bolt hole clearance variation range, make the bolt size and bolt hole clearance variables within the bolt size and bolt hole clearance variation range, and set the minimum iteration step size;

[0030] Determine the allowable stress value of each layer of the nozzle U-shaped component and the allowable value of the bolt load, so that the stress value of each layer of the material is less than the allowable stress value of each layer of the material, and the radial and axial bolt loads are respectively less than the corresponding allowable bolt load values;

[0031] With the goal of minimizing the bolt hole gap, thermal matching optimization is performed to obtain the bolt size and bolt hole gap of each row of the nozzle U-shaped component.

[0032] In an optional embodiment of the present application, the thermal matching optimization calculation of the nozzle U-shaped component is performed based on the Optimus software, and the process includes:

[0033] Firstly, parameter sensitivity analysis is performed to obtain the corresponding relationship between the response parameters including the maximum stress value of each layer, the maximum axial and tangential loads of the bolts, and the gaps between each row of bolt holes and the variable parameters including the bolt size and the gaps between bolt holes in the design space.

[0034] Then, the system response surface model is obtained by interpolation method to analyze the influence of response parameters and variable parameters;

[0035] Finally, multi-objective optimization was performed based on the system response surface model to obtain the bolt size and bolt hole clearance of each row of the nozzle U-shaped component.

[0036] In an optional implementation of the present application, a Python script is used to store the maximum stress value of each layer, the maximum axial and tangential nail loads of the bolts, and the response parameters of the gaps between each row of bolt holes, so that the Optimus software can retrieve the text content for iterative optimization.

[0037] This application targets the U-shaped components of nozzles in high-temperature environments. Through unit-level and component-level structural parameterized models, combined with the idea of ​​material / structure integrated design, the thermal protection / thermal matching optimization design of the U-shaped components of the nozzles is carried out with responses such as structural weight, insulation layer temperature, maximum structural stress and nail load as optimization constraints or targets, and the optimal thickness ratio of each layer of the U-shaped components of the nozzles and the best connection scheme are obtained to achieve the purpose of alleviating structural thermal stress and realize the integrated design of structural protection / insulation and load-bearing. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] In order to more clearly illustrate the technical solution provided by the present application, the following is a brief introduction to the accompanying drawings. Obviously, the accompanying drawings described below are only some embodiments of the present application.

[0039] Figure 1 Schematic diagram of the thermal matching optimization method for the U-shaped component of the nozzle of the present application.

[0040] Figure 2 This is a schematic diagram of a typical TPS structure in this application.

[0041] Figure 3 Schematic diagram of a typical TPS structure finite element model in this application.

[0042] Figure 4 Schematic diagram of the U-shaped nozzle component in this application.

[0043] Figure 5 This is a schematic diagram of the temperature zone loading of the U-shaped component of the nozzle in this application.

[0044] Figure 6 It is a schematic diagram of the partial connection of the U-shaped component of the nozzle in this application.

[0045] Figure 7 This is a schematic diagram of the load boundary of the U-shaped component of the nozzle in this application.

[0046] Figure 8 Schematic diagram of a typical TPS structure optimization process in this application.

[0047] Fig. 9 Schematic diagram of the optimization process of a typical nozzle U-shaped component in this application. DETAILED DESCRIPTION

[0048] In order to make the purpose, technical solutions and advantages of the implementation of this application clearer, the technical solutions in the embodiments of this application will be described in more detail below in conjunction with the drawings in the embodiments of this application.

[0049] Aiming at the U-shaped components of the nozzle in harsh environments, combined with the requirements of heat insulation, load-bearing, lightweight, etc., in order to carry out integrated design of thermal protection materials / structures, this application has established a thermal matching optimization method. By establishing a multi-scale parametric model of the nozzle U-shaped components and introducing connection units to simulate bolt connections, thermal protection / thermal matching design is carried out to achieve thermal stress relief of the structure, and obtain the optimal thickness ratio of each layer of the nozzle U-shaped components and the best connection scheme.

[0050] like Figure 1 As shown, the high-temperature nozzle U component thermal matching optimization method provided by the present application includes the following process:

[0051] Step S100: parametric modeling of a typical TPS structure and a nozzle U-shaped component.

[0052] Parametric models of typical TPS structures and nozzle U-shaped components were established, where the variable parameters of the typical TPS structure included the thickness of each layer of material, and the variable parameters of the nozzle U-shaped components included the bolt size and bolt hole clearance. The two parameterized models were used to explore the influence of the thickness distribution of each material on the anti-heat / insulation performance of the typical TPS structure and the influence of the bolt connection parameters on the thermal stress release of the nozzle U-shaped components.

[0053] The thermal protection structure (TPS) is a multi-layer composite structure. In view of the high temperature and harsh environment of the nozzle, the present application uses a typical TPS structure consisting of a thermal protection layer and two thermal insulation layers, which are the same as the thermal protection structure of the U-shaped component of the nozzle. Figure 2 As shown, the heat-proof layer 11 is arranged at the outermost side, and its front side is directly subjected to the high temperature environment. The first heat-insulating layer 12 is located in the middle, and the second heat-insulating layer 13 is located at the innermost side. The two heat-insulating layers are used to reduce the temperature of the internal structure.

[0054] The established parameterized model of a typical TPS structure includes three layers, namely, a heat protection layer 11, a first heat insulation layer 12, and a second heat insulation layer 13. Figure 3 As shown, using the Transfer analysis step, a thermal environment temperature of T is applied to the upper surface of the heat protection layer 11. E , the radiation boundary condition with a radiation coefficient of η1, and an ambient temperature of T is applied to the lower surface and surrounding of the second thermal insulation layer 13 k The heat dissipation radiation boundary condition with a radiation coefficient of η2 (for example, it can be set to 300K), a contact thermal resistance R1 is set between the two layers, the equivalent thermal conductivity is ζ, the heating is a transient process, and the time is t1, thereby completing the parametric modeling that can be used for heat transfer analysis.

[0055] like Figure 4 The figure shows the finite element model of heat transfer analysis of the nozzle-shaped component established in this embodiment of the present application. The model includes a heat protection layer 21, a first heat insulation layer 22, a second heat insulation layer 23 and a metal outer load-bearing skin 24 from the inside to the outside. The metal outer load-bearing skin 24 is provided with ribs 25 that can enhance the structural strength. The various layers of the structure are connected by multiple rows of bolts 26, thereby forming an integrated structure of heat protection / insulation and load-bearing. Figure 5 As shown in FIG. 1 , the Transfer analysis step is used to set the initial temperature of the nozzle U-shaped component to T (for example, it can be set to 300K), and the interior of the nozzle U-shaped component is divided into three temperature zones according to the actual working conditions. A thermal radiation boundary condition with a radiation coefficient of η1 is applied to the outer surface of the heat protection layer 21 in the three temperature zones, and an ambient temperature of T is applied to the outermost layer of the metal outer load-bearing skin 24. k(For example, it can be set to 300K), the heat dissipation radiation boundary condition of the radiation coefficient η2, the contact thermal resistance is set between each layer, the equivalent thermal conductivity is ζ, the heating is a transient process, the time is t1, and the establishment of the finite element model of heat transfer analysis is completed.

[0056] Combination Figure 6 and Figure 7 Based on the finite element model of heat transfer analysis of the nozzle U-shaped component, the Fasteners connection unit is introduced to simulate the bolt connection, so as to establish a thermomechanical coupling parameterized model of the nozzle U-shaped component. The thermomechanical coupling parameterized model of this embodiment of the present application includes 14 rows of bolts 26, and the parameters of the bolts 26 in each row are the same. Since the thermomechanical coupling parameterized model is a symmetrical structure, only the 7 rows of bolts 26 on one side are marked in the figure, and the other side is not marked. The parameter settings of the symmetrical bolt holes in the thermomechanical coupling parameterized model are the same, so the design variables are halved. The variable parameters include bolt size and bolt hole gap, a total of 14 variable parameters. The bolt size and bolt hole gap are set by modifying the Fastener unit properties. The bolt sizes are set to d1, d2, d3, d4, d5, d6, and d7 in sequence, and the bolt hole gaps are set to stop1, stop2, stop3, stop4, stop5, stop6, and stop7 respectively. The Static analysis step is adopted, and the temperature boundary uses the heat transfer analysis results to map the temperature field. At the same time, the simply supported boundary conditions are applied to the outermost layer, and the aerodynamic pressure load is applied to the inner layer, thereby completing the establishment of the thermal-mechanical coupling parameterized model, and thermal-mechanical coupling calculations can be performed.

[0057] In the present application, the parametric model of the typical TPS structure and the nozzle U-shaped component mentioned above can be established based on Abaqus simulation software.

[0058] Step S200, heat transfer optimization design of a typical TPS structure.

[0059] Using the typical TPS structure established in step S100, with the thickness of each layer as the variable parameter, the total thickness of the TPS and the temperature of the insulation layer as constraints, and the minimum total weight of the typical TPS structure as the goal, heat transfer optimization design is carried out to obtain the optimal thickness ratio scheme of each layer.

[0060] In view of the high temperature environment of the nozzle, the thermal protection optimization design is carried out. In this embodiment of the present application, the thickness of each layer of the typical TPS structure is the thickness of the heat protection layer h1, the thickness of the first heat insulation layer h2 and the thickness of the second heat insulation layer h3, wherein the variation range of the thickness of each layer is set to 1mm

[0061] To facilitate parameter iteration and the setting of optimization constraints and objectives during optimization, this application uses a Python parameterized script to output response parameters such as the total thickness of the structure, the temperature of the first insulation layer, the temperature of the second insulation layer, the temperature of the back of the second insulation layer, and the total weight of the structure to the corresponding text, and the Optimus software retrieves the text content for iterative optimization.

[0062] like Figure 8 As shown in the figure, the optimization design process is built based on Optimus software, and Latin hypercube is selected for parameter sensitivity analysis to obtain the corresponding relationship between response parameters (TPS total thickness, insulation layer temperature, total weight of structure, etc.) and variable parameters (i.e. thickness of each layer) in the design space. Then, the RBF interpolation method is selected to obtain the response surface model of the system, analyze the influence of each variable parameter on the optimization target, and reduce physical calculations. Finally, based on the established response surface model, the non-controlled sorting evolutionary algorithm (NSEA+) is used for rapid multi-objective optimization to obtain the optimal thickness ratio scheme for each layer.

[0063] Step S300, thermal matching optimization design of the nozzle U-shaped component.

[0064] A parametric model of the nozzle U-shaped component was established based on the optimal thickness ratio of each layer obtained from the heat transfer optimization of the typical TPS structure. A connection unit was introduced to simulate the bolt connection. The bolt size and bolt hole gap were used as variable parameters, the stress of each layer of the nozzle U-shaped component and the nail load were used as constraints, and the minimum bolt hole gap was used as the goal. The thermal matching optimization design of the nozzle U-shaped component was carried out to reduce the bolt hole gap while achieving the purpose of thermal stress relief, and to reduce the air intake to ensure the thermal sealing effect.

[0065] ​Based on the optimal thickness ratio of each layer obtained after the typical TPS structure optimization, a thermomechanical coupling parameterized model of the nozzle U-shaped component is established for thermomechanical coupling simulation calculation. In this calculation process, the design variables include 14 variable parameters including bolt size and bolt hole gap. The bolt size is set to d1, d2, d3, d4, d5, d6, and d7 in sequence, and the bolt hole gap is set to stop1, stop2, stop3, stop4, stop5, stop6, and stop7 respectively. The bolt size varies from 4mm to 12mm, and the bolt hole gap varies from 0.1mm to 2mm. The minimum iteration step is set to 0.1. The stress and nail load of each layer of the nozzle U-shaped component are constrained, among which the stress value of the heat protection layer 21 is <σ1, the stress value of the first heat insulation layer 22 is <σ2, the stress value of the second heat insulation layer 23 is <σ3, the stress value of the metal outer bearing layer 24 is <σ4, and the tangential nail load of the bolt 26 is <σ4. <F r , bolt 26 axial nail load <F t , σ1, σ2, σ3 are the maximum allowable stress values ​​of the heat protection layer material, the first insulation layer material and the second insulation layer material, respectively. r 、F t They are the allowable values ​​of the tangential nail load of the bolt and the allowable values ​​of the axial nail load of the bolt. With the goal of minimizing the bolt hole gap, thermal matching optimization is performed to obtain the bolt size and bolt hole gap of each row. In order to facilitate parameter iteration and the setting of optimization constraints and goals during optimization, the maximum stress value of each layer, the maximum axial and tangential nail load of the bolt, and the gap of each row of bolt holes can be output to the corresponding text through Python parameterized scripts. Optimus software performs iterative optimization by calling the text content.

[0066] like Fig. 9 As shown in the figure, the optimization design process is built based on Optimus software, and Latin hypercube is selected for parameter sensitivity analysis to obtain the corresponding relationship between response parameters (maximum stress value of each layer, maximum axial and tangential nail load of bolts, and gap of bolt holes in each row) and variable parameters (size of bolts in each row and gap of bolt holes) in the design space. Then, the RBF interpolation method is selected to obtain the response surface model of the system, analyze the influence of each variable parameter on the optimization target, and reduce physical calculations. Finally, based on the established response surface model, the non-controlled sorting evolutionary algorithm (NSEA+) is used for rapid multi-objective optimization to obtain the optimal bolt connection scheme for the U-shaped component of the nozzle, which reduces the gap of bolt holes while achieving the purpose of thermal stress relief, and reduces the air intake to ensure the thermal sealing effect.

[0067] This application targets the U-shaped components of nozzles in high-temperature environments. Through unit-level and component-level structural parameterized models, combined with the idea of ​​material / structure integrated design, the thermal protection / thermal matching optimization design of the U-shaped components of the nozzles is carried out with responses such as structural weight, insulation layer temperature, maximum structural stress and nail load as optimization constraints or targets. The optimal thickness ratio of each layer of the Ux-shaped components of the nozzles and the best connection scheme are obtained to achieve the purpose of alleviating structural thermal stress and realize the integrated design of structural protection / insulation and load-bearing.

[0068] The above is only a specific implementation of the present application, but the protection scope of the present application is not limited thereto. Any changes or substitutions that can be easily thought of by a person skilled in the art within the technical scope disclosed in the present application should be included in the protection scope of the present application. Therefore, the protection scope of the present application shall be based on the protection scope of the claims.

Claims

1. A method for optimizing thermal matching of a high-temperature nozzle U-shaped component, characterized in that: include: Step S100, constructing a parameterized model of a nozzle U-shaped component and a typical TPS structure, wherein the typical TPS structure is the same as the thermal protection structure of the nozzle U-shaped component, and the typical TPS structure is a multi-layer material composite structure consisting of at least an outermost heat protection layer and a heat insulation layer located inside the heat protection layer; Step S200, based on the parameterized model of the typical TPS structure, taking the thickness of each layer as a variable, taking the total thickness of the TPS and the temperature of the insulation layer as constraints, and taking the minimum weight of the typical TPS structure as the goal, a typical TPS structure heat transfer optimization design is carried out to obtain the optimal thickness ratio of each layer of the typical TPS structure; Step S300, applying the optimal thickness ratio of each layer of the typical TPS structure to the parametric model of the nozzle U-shaped component, taking the bolt size and bolt hole gap of the bolts connecting each layer as variables, taking the stress and nail load of each layer of the nozzle U-shaped component as constraints, and taking the minimum bolt hole gap as the goal, the nozzle U-shaped component thermal matching optimization design is carried out to obtain the optimal bolt size and bolt hole gap of the nozzle U-shaped component.

2. The high-temperature nozzle U-shaped component thermal matching optimization method according to claim 1, characterized in that: The parameterized models of the nozzle U-shaped component and the typical TPS structure were established using Abaqus software.

3. The high-temperature nozzle U-shaped component thermal matching optimization method according to claim 2, characterized in that: The process of establishing a typical TPS structural parametric model using Abaqus software is as follows: First, a parameterized model of a typical TPS structure is established; Using the Transfer analysis step, a thermal environment temperature of T is applied to the upper surface of the heat protection layer. E , radiation boundary conditions with a radiation coefficient of η1, and an ambient temperature of T is applied to the lower surface and surrounding of the insulation layer. k , the heat dissipation radiation boundary condition with a radiation coefficient of η2, the contact thermal resistance R1 is set between the two adjacent layers, the equivalent thermal conductivity is ζ, the heating is a transient process, and the time is t1, thereby completing the parametric modeling of the typical TPS structure.

4. The high-temperature nozzle U-shaped component thermal matching optimization method according to claim 3, characterized in that: The process of carrying out heat transfer design of a typical TPS structure to obtain the optimal thickness ratio of each layer of the typical TPS structure is as follows: Determine the thickness variables of each layer of the typical TPS structure and the thickness variation range of each layer, so that the thickness variables of each layer of the typical TPS structure are within the thickness variation range of each layer, and set the minimum iteration step size; Determine the thermal insulation layer temperature constraint, including the thermal insulation layer material temperature allowable value and the innermost thermal insulation layer backside temperature maximum value, so that the thermal insulation layer temperature is less than the thermal insulation layer material temperature allowable value, and the innermost thermal insulation layer backside temperature is less than the innermost thermal insulation layer backside temperature maximum value; Determine the total thickness of the TPS structure so that the sum of the thicknesses of each layer is less than the total thickness of the TPS structure; With the goal of minimizing the total weight of the TPS structure, heat transfer optimization is performed to achieve the optimal thickness ratio of each layer of the typical TPS structure.

5. The high-temperature nozzle U-shaped component thermal matching optimization method according to claim 4, characterized in that: Based on Optimus software, the heat transfer optimization calculation of typical TPS structure is carried out. The process includes: Firstly, parameter sensitivity analysis is performed to obtain the corresponding relationship between the response parameters including the total thickness of TPS, the temperature of the thermal insulation layer, the total weight of the structure and the variable parameters of the thickness of each layer in the design space; Then, the system response surface model is obtained by interpolation method to analyze the influence of response parameters and variable parameters; Finally, multi-objective optimization was performed based on the system response surface model to obtain the optimal thickness ratio of each layer of the TPS structure.

6. The method for optimizing thermal matching of a high-temperature nozzle U-shaped component according to claim 4 or 5, characterized in that: The response parameters of TPS total thickness, insulation layer temperature and total structure weight are stored through Python scripts, making it easy for Optimus software to retrieve text content for iterative optimization.

7. The high-temperature nozzle U-shaped component thermal matching optimization method according to claim 6, characterized in that: The process of establishing the parametric model of the nozzle U-shaped component through Abaqus software is as follows: Firstly, a finite element model for heat transfer analysis of the nozzle U-shaped component is established, which includes the heat protection layer, the heat insulation layer and the metal outer load-bearing skin from the inside to the outside. The Transfer analysis step is used to set the initial temperature of the nozzle U-shaped component to T. The interior of the nozzle U-shaped component is divided into three temperature zones according to the actual working conditions. Thermal radiation boundary conditions with a radiation coefficient of η1 are applied to the outer surface of the heat protection layer in the three temperature zones. The ambient temperature of T is applied to the outermost layer of the metal outer load-bearing skin. k , the heat dissipation radiation boundary condition of the radiation coefficient η2, the contact thermal resistance is set between each layer, the equivalent thermal conductivity is ζ, the heating is a transient process, the time is t1, and the establishment of the finite element model of heat transfer analysis is completed; Based on the heat transfer analysis finite element model, Fasteners connection units are introduced to simulate the bolt connection between layers, and the bolt size and bolt hole gap are set by modifying the Fasteners unit properties; The Static analysis step is adopted, and the temperature boundary uses the heat transfer analysis results to map the temperature field. At the same time, the simply supported boundary condition is applied to the outermost layer, and the aerodynamic pressure load is applied to the inner layer, thereby completing the establishment of the parametric model of the nozzle U-shaped component for thermal-mechanical coupling calculation.

8. The method for optimizing thermal matching of a high-temperature nozzle U-shaped component according to claim 7, characterized in that: The process of carrying out the thermal matching optimization design of the nozzle U-shaped component to obtain the optimal bolt size and bolt hole clearance of the nozzle U-shaped component is as follows: Determine the bolt size and bolt hole clearance variables and the bolt size and bolt hole clearance variation range, make the bolt size and bolt hole clearance variables within the bolt size and bolt hole clearance variation range, and set the minimum iteration step size; Determine the allowable value of material stress of each layer of the nozzle U-shaped component and the allowable value of bolt nail load, so that the stress value of each layer of material is less than the allowable value of material stress of each layer, and the radial and axial nail loads of the bolts are respectively less than the corresponding allowable values ​​of bolt nail loads; With the goal of minimizing the bolt hole gap, thermal matching optimization is performed to obtain the bolt size and bolt hole gap of each row of the nozzle U-shaped component.

9. The high-temperature nozzle U-shaped component thermal matching optimization method according to claim 8, characterized in that: The thermal matching optimization calculation of the nozzle U-shaped component is carried out based on Optimus software. The process includes: Firstly, parameter sensitivity analysis is performed to obtain the corresponding relationship between the response parameters including the maximum stress value of each layer, the maximum axial and tangential nail load of the bolt, and the gap between each row of bolt holes and the variable parameters including the bolt size and bolt hole gap in the design space; Then, the system response surface model is obtained by interpolation method to analyze the influence of response parameters and variable parameters; Finally, multi-objective optimization was performed based on the system response surface model to obtain the bolt size and bolt hole clearance of each row of the nozzle U-shaped component.

10. The method for optimizing thermal matching of a high-temperature nozzle U-shaped component as claimed in claim 9, characterized in that: The maximum stress value of each layer, the maximum axial and tangential nail load of the bolt, and the response parameters of the gap between each row of bolt holes are stored through Python scripts, making it easy for Optimus software to retrieve text content for iterative optimization.

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