Spraying pipe heat insulation assembly bolt arrangement design method based on topological optimization

Abstract

The invention provides a nozzle heat insulation assembly bolt arrangement design method based on topological optimization, and belongs to the technical field of aero-engines, and the method specifically comprises the steps that a simplified analysis model is established for a heat insulation assembly, the heat insulation assembly comprises an impact layer, a bulge layer and an air film layer, the bulge layer and the air film layer are welded to form a heat insulation layer, and a bolt is welded to the bulge layer; the bolt is used for connecting an impact layer and a hook on the impact layer, and the bolt is simplified into a beam unit; determining an initial bolt layout of the simplified analysis model by adopting a multi-working-condition topological optimization method based on weighted compliance response; and detail optimization based on assembly constraint is carried out on the initial layout of the bolts, and the optimal layout of the bolts is obtained. By means of the processing scheme, the calculation efficiency of bolt optimization design and the sealing reliability and cooling efficiency of the spray pipe heat insulation assembly are improved, and the design scheme has the optimal performance and the engineering practicability at the same time.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of aero-engines, and particularly relates to a bolt arrangement design method for a nozzle heat-insulating assembly based on topological optimization. BACKGROUND

[0002] In recent years, with the rapid increase of parameters such as the working pressure and the combustion temperature of an engine combustion chamber, the thermal load borne by a nozzle increases sharply, and the nozzle faces severe cooling challenges. The combined mode of impingement cooling and film cooling is one of the effective methods for protecting the nozzle shell from high-temperature damage. Specifically, the cold gas cavity is provided in a double-layer structure: the first layer is an impingement plate, small holes are arranged on the impingement plate and are perpendicular to the wall surface, and the cold gas first passes through the small holes on the impingement plate to impinge and exchange heat with the wall surface of the heat-insulating layer; then, the cold gas enters the main flow through the inclined holes on the heat-insulating layer to form a film cooling layer. This cooling mode leads to more complex design of the nozzle structure, and the connection mode between the heat-insulating layer and the impingement plate and the flow characteristics of the cold gas cavity directly affect the structural strength and reliability, bringing many challenges to the design.

[0003] At present, the impingement plate is designed as a whole large plate, the heat-insulating layer is designed as a segmented structure, and the heat-insulating layer and the impingement plate are mainly connected by bolts. However, the arrangement form (such as the interval and the position) of the bolts depends on engineering experience to a great extent, and the structural difference (there are circular arc segments and straight segments, and the lengths and shapes of the segments are different) and the load difference (the loads of the segments are quite different, and the loads of various test conditions are different) of different heat-insulating assembly segments cannot be fully considered. This usually leads to redundancy of the number of bolts, and the weight of the structure is difficult to effectively control; at the same time, in the key area that needs to be sealed, the structural deformation may be too large, which seriously affects the sealing reliability and the cooling efficiency. SUMMARY

[0004] Therefore, the embodiments of the present application provide a bolt arrangement design method for a nozzle heat-insulating assembly based on topological optimization, which can minimize the number of bolts by optimizing the force transmission path under the premise of guaranteeing the structural strength, the rigidity, the assembly feasibility, the sealing requirement of key areas of the heat-insulating assembly, and ensure that the bolt load distribution is more uniform, finally improve the sealing reliability and the cooling efficiency of the heat-insulating assembly, and reduce the structural weight.

[0005] The embodiments of the present application provide a bolt arrangement design method for a nozzle heat-insulating assembly based on topological optimization, which comprises the following steps:

[0006] A simplified analysis model of the heat-insulating assembly is established, the heat-insulating assembly comprises an impingement layer, a bulge layer and a film layer, the bulge layer and the film layer are welded to form a heat-insulating layer, and a bolt is welded on the bulge layer and used to connect the impingement layer and a hook on the impingement layer; the bolt is simplified as a beam element; An initial bolt layout of the simplified analysis model is determined by using a multi-condition topology optimization method based on a weighted flexibility response; An optimal bolt layout is obtained by performing a detail optimization based on assembly constraints on the initial bolt layout.

[0007] According to a specific implementation manner of the embodiment of the application, the establishing of the simplified analysis model for the thermal insulation assembly comprises: The impact plate is simplified as a constraint position; The thermal insulation layer is simulated by using a shell element.

[0008] According to a specific implementation manner of the embodiment of the application, the initial bolt layout of the simplified analysis model is determined by using a multi-condition topology optimization method based on a weighted flexibility response, which comprises: A designable domain is defined, and a relative density of a beam element in the designable domain is taken as an optimization design variable; Under an optimization constraint condition, a topology optimization is performed on the relative density of the beam element in the designable domain to obtain the initial bolt layout, with a minimum weighted flexibility of the thermal insulation assembly under all test conditions as an optimization target based on the simplified analysis model.

[0009] According to a specific implementation manner of the embodiment of the application, the defining of the designable domain comprises: According to a function and assembly requirement of the thermal insulation assembly, an area between bulges where no bolt can be arranged and an area between bulges where a bolt must be arranged are defined as an undesignable domain, and a remaining area between the bulges is taken as the designable domain.

[0010] According to a specific implementation manner of the embodiment of the application, the relative density of the beam element in the designable domain is taken as the optimization design variable, which comprises: A mapping relationship between the design variable and a material attribute is established based on an interpolation model of the material, and the relative density of the beam element is made close to 0 or 1 by controlling a density and stiffness relationship of the beam element; When the relative density of the beam element is close to 1, it indicates that a bolt needs to be arranged at the position; and when the relative density of the beam element is close to 0, it indicates that no bolt needs to be arranged at the position.

[0011] According to a specific implementation manner of the embodiment of the application, the optimization constraint condition comprises: A maximum tensile load borne by a single bolt satisfies the following relationship: ≤ , wherein F z is the maximum tensile load, d is a bolt diameter, is a buckling strength limit of the material; A maximum displacement of the thermal insulation layer does not exceed a design allowable value; A structural symmetry constraint condition is applied.

[0012] According to an implementation of the embodiment of the present application, the relative density of the beam unit in the designable domain is topologically optimized with the minimum weighted compliance of the thermal insulation assembly under all test conditions as the optimization target, including: calculating the initial compliance of the thermal insulation assembly under each test condition i and the total tensile load borne by all bolts ; calculating the total tensile load of each test condition i and the total tensile load of the preset reference condition ratio K Fi ; correcting the initial compliance of each test condition i based on the ratio K Fi to obtain the corrected compliance C of each test condition i mi ; determining the compliance weight coefficient of each test condition i ; topologically optimizing the relative density of the beam unit in the designable domain based on the corrected compliance C mi and the compliance weight coefficient with the minimum weighted compliance of the thermal insulation assembly under all test conditions as the optimization target.

[0013] According to an implementation of the embodiment of the present application, the expression of the corrected compliance C mi is as follows: .

[0014] According to an implementation of the embodiment of the present application, the expression of the weighted compliance is as follows: , wherein C w is the weighted compliance.

[0015] According to an implementation of the embodiment of the present application, the initial layout of the bolts is optimized based on assembly constraints, including: identifying the region where the relative density of the beam unit approaches 1 in the initial layout of the bolts as a bolt position candidate point; determining assembly constraints, the assembly constraints including that the bolts at the hook position need to appear in pairs, and the adjacent bolts are separated by a column of bulges in the middle to ensure assembly space; redesigning the designable domain and the non-designable domain based on the assembly constraints for the bolt position candidate point; topologically optimizing on the redesigned designable domain to obtain the optimal layout of the bolts that satisfies the strength, stiffness and assembly feasibility.

[0016] Beneficial effects: The topology-optimized bolt arrangement design method for nozzle heat insulation components in this application has the following significant advantages and positive effects compared to existing design methods that rely on engineering experience: a) High computational efficiency: By reasonably simplifying the modeling of the impact plate, bolts, and insulation layer, the model complexity is significantly reduced, and the computational efficiency of topology optimization is improved; b) Improved Design: A multi-condition topology optimization method based on weighted compliance response is adopted, using the relative density of bolt elements as the design variable. Under the strict constraints of bolt strength (maximum tensile load) and insulation layer stiffness (maximum displacement), the overall weighted compliance of the insulation component is minimized. This is equivalent to optimizing the force transmission path of the structure, making load transfer more direct and efficient. c) Improved reliability: The optimized bolt arrangement results in a more uniform distribution of bolt load, avoiding stress concentration; at the same time, it effectively controls the deformation of the sealing area, significantly reduces the risk of cold air leakage, and significantly improves the sealing reliability and cooling efficiency of the nozzle heat insulation component. d) Comprehensive consideration: Innovatively adopting a two-order optimization strategy, firstly, the bolt layout prototype with optimal force transmission is obtained through topology optimization, and then detailed optimization is carried out in combination with specific assembly constraints to ensure that the design scheme has both optimal performance and engineering practicality. Attached Figure Description

[0017] To more clearly illustrate the technical solutions of the embodiments of this application, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0018] Figure 1 This is a flowchart of a topology-optimized bolt arrangement design method for a nozzle heat insulation assembly according to an embodiment of the present invention; Figure 2 This is a schematic diagram of a heat insulation component structure according to an embodiment of the present invention; Figure 3 This is a schematic diagram of an initial model of a thermal insulation component according to an embodiment of the present invention; Figure 4 This is an optimization analysis model according to an embodiment of the present invention; Figure 5 This is a schematic diagram of the relative density distribution of beam units in a thermal insulation component according to an embodiment of the present invention; Figure 6 This is an optimized model according to an embodiment of the present invention; Figure 7Fig. 2 is a schematic view of a sealing area deformation result of a thermal insulation assembly according to an embodiment of the present application.

[0019] Fig. 1 is a schematic view of a thermal insulation assembly according to an embodiment of the present application. DETAILED DESCRIPTION

[0020] The embodiments of the present application will be described in detail with reference to the drawings, wherein:

[0021] The above embodiments are only used to illustrate the technical solutions of the present application, and are not used to limit the scope of the present application. Therefore, although the present application has been described in detail with reference to the embodiments, those skilled in the art will understand that the technical solutions of the present application can be modified or equivalent substitutes can be used without departing from the spirit and scope of the present application. Therefore, the scope of protection of the present application should be subject to the scope of protection of the claims.

[0022] It is to be understood that the foregoing description is merely illustrative of various aspects of embodiments described in the claims. Accordingly, no limitation is implied based on the description as recited in the specification that defines embodiments of the application with regard to any particular aspect of the application. Rather, the scope of the application is to be understood only in terms of the following claims. Furthermore, it is to be understood that the aspects of the application described herein can be implemented in various forms of hardware, software, or a combination thereof, and that the application should not be limited to any particular aspects described herein, but should be understood to include all aspects within the scope of the appended claims, including both the specific aspects described and other aspects that are not specifically described.

[0023] It is also to be understood that the above description is only illustrative of the aspects of the embodiments described in the claims. Accordingly, no limitation is implied based on the description as recited in the specification that defines embodiments of the application with regard to any particular aspect of the application. Rather, the scope of the application is to be understood only in terms of the following claims. Furthermore, it is to be understood that the aspects of the application described herein can be implemented in various forms of hardware, software, or a combination thereof, and that the application should not be limited to any particular aspects described herein, but should be understood to include all aspects within the scope of the appended claims, including both the specific aspects described and other aspects that are not specifically described.

[0024] Also in the following description, specific details are provided to thoroughly understand examples. It will be apparent to those skilled in the art, however, that the described aspects can be practiced without these specific details.

[0025] The embodiment of the present application provides a bolt arrangement design method of a nozzle heat-insulating assembly based on topology optimization. Figures 1 to 7 The embodiment of the present application provides a bolt arrangement design method of a nozzle heat-insulating assembly based on topology optimization.

[0026] In one embodiment, referring to Figure 1 The embodiment of the present application provides a bolt arrangement design method of a nozzle heat-insulating assembly based on topology optimization. Step S101, a simplified analysis model of the heat-insulating assembly is established, the heat-insulating assembly comprises an impact layer 1, a bulge layer 3 and a gas film layer 4, the bulge layer 3 and the gas film layer 4 are welded to form a heat-insulating layer, a bolt 2 is welded on the bulge layer 3 and used for connecting the impact layer 1 and a hook 5 on the impact layer 1, and the bolt 2 is simplified as a beam unit; Step S102, a bolt 2 initial arrangement of the simplified analysis model is determined by using a multi-working-condition topology optimization method based on weighted compliance response; Step S103, a bolt 2 optimal arrangement is obtained by performing a detail optimization based on assembly constraints on the bolt 2 initial arrangement.

[0027] In specific implementation, referring to Figure 2 The heat-insulating assembly structure mainly comprises three layers: the impact layer 1, the bulge layer 3 and the gas film layer 4, and the model is reasonably simplified according to the structural rigidity and load characteristics of the heat-insulating assembly.

[0028] Further, the step of establishing the simplified analysis model of the heat-insulating assembly comprises: The impact plate is simplified as a constraint position; The heat-insulating layer is simulated by using a shell unit.

[0029] In specific implementation, the impact plate is a whole large plate, the heat-insulating layer is a block structure, the impact plate can be simplified as a constraint position, the connecting bolt 2 is simplified as a beam unit to simulate the connecting and force transmission behavior thereof, and the heat-insulating layer can be simulated by using a shell unit because the size of the heat-insulating layer in the thickness direction is far less than the size in the two in-plane directions.

[0030] In the embodiment, the bulge layer 3 and the gas film layer 4 form a complete heat-insulating layer structure by welding process, and the bolt 2 is welded and fixed at a specific position of the bulge layer 3, which mainly realizes reliable connection between the impact layer 1 and the hook 5 on the impact layer 1. In the model construction process, in order to improve the analysis efficiency on the premise of ensuring the calculation accuracy, the bolt 2 is abstracted and simplified as a beam unit to simulate the stress and force transmission characteristics of the bolt 2 under actual working conditions. An initial model of a certain heat-insulating assembly is shown in Figure 3 and an optimization analysis model is shown in Figure 4.

[0031] In one embodiment, the bolt 2 initial layout of the simplified analysis model is determined by using the multi-working condition topology optimization method based on the weighted flexibility response, including: defining a designable domain, and taking the relative density of the beam element in the designable domain as an optimization design variable; based on the simplified analysis model, performing topology optimization on the relative density of the beam element in the designable domain under the optimization constraint condition, so as to obtain the bolt 2 initial layout, and taking the minimum weighted flexibility of the thermal insulation assembly under all test conditions as an optimization target.

[0032] In this embodiment, in order to realize accurate optimization of the bolt 2 layout, the range of the designable domain needs to be first determined, which needs to cover all possible areas of the thermal insulation assembly where the bolt 2 can be arranged, so as to ensure the comprehensiveness of the optimization result. The relative density of the beam element in the designable domain is set as the optimization design variable. In terms of the optimization constraint condition, the number limit of the bolt 2, the structural strength requirement, the installation space limit and the like are mainly considered, so as to ensure the engineering feasibility of the optimization result. Based on the simplified analysis model, the flexibility of the thermal insulation assembly under various test conditions of the nozzle thermal insulation assembly under different working states, such as the high-temperature working condition, the vibration condition, the impact condition and the like, is calculated. The flexibilities under all test conditions are weighted and summed by assigning the corresponding weight coefficients of different conditions, so as to obtain the weighted flexibility, which is taken as the optimization target, that is, the minimization of the weighted flexibility. In the topology optimization process, the optimization algorithm is used to iteratively update the relative density of the beam element in the designable domain, so as to constantly adjust the existence state of each element, until the weighted flexibility reaches the minimum value. At this time, the position corresponding to the beam element with the relative density of 1 in the designable domain constitutes the initial layout of the bolt 2. The initial layout can make the overall stiffness of the thermal insulation assembly optimal under the premise of meeting the requirements of various conditions, and provides a reliable basis for the subsequent detailed design of the bolt 2 layout.

[0033] Further, the definition of the designable domain includes: According to the function and assembly requirement of the thermal insulation assembly, the area between the bulges where the bolt 2 cannot be arranged and the area between the bulges where the bolt 2 must be arranged are defined as the non-designable domain 18, and the remaining area between the bulges is taken as the designable domain.

[0034] In specific implementation, refer to Figure 3For example, taking a certain thermal insulation assembly as an example, a symmetry plane 12 is arranged, and the right side area of the symmetry plane 12 is taken as an example. The first column of bulge areas 11 on the right side starts from the edge, and the bolts 2 must be arranged due to sealing requirements. Such bolts 2 are defined as first bolts 21, and the corresponding area is defined as an undesignable domain 18. The second column of bulge areas 15 and the fourth column of bulge areas 17 cannot be arranged with bolts 2 due to the need to reserve sufficient space for mounting the hooks 5. The corresponding area here is also the undesignable domain 18. For the designable domain, it can be further divided into a first designable domain 19 and a second designable domain 20. For example, the third column of bulge areas 16 needs to be arranged with bolts 2 due to the hook 5 assembly requirement (the position of the hook 5 is determined first). Such bolts 2 are defined as second bolts 22, and the corresponding area is defined as the first designable domain 19. The bolts 2 can also be established between the bulges from the fifth column of bulges to the symmetry plane, and the area is defined as the second designable domain 20. The first designable domain 19 and the second designable domain 20 can both be arranged with bolts 2.

[0035] In a specific implementation, the above-mentioned way of dividing the designable domain and the undesignable domain 18 can effectively exclude the area where the bolts 2 cannot be arranged due to functional limitations or assembly conflicts, ensure that the topology optimization is only performed in the feasible space, and avoid invalid calculation. This domain division method based on actual engineering constraints lays an important foundation for the accuracy and engineering practicability of subsequent topology optimization.

[0036] In one embodiment, the relative density of the beam element in the designable domain is taken as an optimization design variable, which includes: A material-based interpolation model is used to establish a mapping relationship between the design variable and the material attribute (such as Young's modulus and density), and the relative density of the beam element is controlled to approach 0 or 1 by controlling the density and stiffness relationship of the beam element. When the relative density of the beam element approaches 1, it indicates that the bolt 2 needs to be arranged at this position; when the relative density of the beam element approaches 0, it indicates that the bolt 2 does not need to be arranged at this position.

[0037] In one embodiment, the optimization constraint condition includes: The maximum tensile load borne by a single bolt 2 does not exceed the allowable value, and the following relationship holds: ≤ , wherein F z is the maximum tensile load, d is the diameter of the bolt 2, is the buckling strength limit of the material; The maximum displacement of the thermal insulation layer does not exceed the design allowable value; A structural symmetry constraint condition is applied, such as Figure 3 the symmetry plane 12 in the YZ plane.

[0038] Furthermore, the optimization objective is to minimize the weighted compliance of the thermal insulation component under all test conditions, and topology optimization is performed on the relative density of beam elements within the designable domain, including: Based on the initial model, the initial compliance of the thermal insulation component under each test condition i is calculated. and the total tensile load borne by all bolts 2 ; Calculate the total tensile load for each test condition i. Total tensile load compared to a preset reference condition (e.g., design point condition) Ratio K Fi ; Based on the ratio K Fi Initial compliance for each test condition i Make corrections to obtain the corrected compliance C for each test condition i. mi The aim is to balance the contribution of compliance under different load levels; Determine the compliance weighting coefficient for each assessment condition i. Weights can be assigned based on the importance of the working condition or the probability of its occurrence. Based on the modified compliance C mi Compliance weighting coefficient With the goal of minimizing the weighted compliance of the thermal insulation components under all test conditions, topology optimization is performed on the relative density of beam elements within the designable domain to obtain the topology-optimized configuration of the bolt 2 layout, i.e., the relative density distribution cloud map of the beam elements, as shown below. Figure 5 As shown, Figure 5 The model results for one side of symmetry plane 12 are shown in the figure.

[0039] Furthermore, the corrected compliance C mi The expression is: .

[0040] Furthermore, the expression for the weighted compliance is: , Among them, C w For weighted compliance.

[0041] In one embodiment, the detailed optimization of the initial layout of bolt 2 based on assembly constraints includes: In the initial layout of bolt 2, regions where the relative density of beam elements approaches 1 are identified as candidate points for the location of bolt 2; Determine the assembly constraints, including that the bolts 2 at the hook 5 position must appear in pairs, and that adjacent bolts 2 must be separated by a row of bulges to ensure assembly space; Based on the assembly constraint, the position candidate points of the bolts 2 are re-divided into the designable domain and the non-designable domain 18; The topology optimization is performed on the re-divided designable domain to obtain the optimal layout of the bolts 2 that meet the strength, stiffness and assembly feasibility.

[0042] In a specific implementation, the detail optimization based on the assembly constraint specifically includes the following contents: According to the topology optimization result of step S102, the high-density area is identified as a potential bolt 2 position candidate point; Since the connecting bolts 2 need to be reliably connected with the hooks 5, the bolts 2 at the positions of the hooks 5 need to appear in pairs, and a column of bulges is arranged between the adjacent bolts 2 to ensure the assembly space; Based on the topology optimization result, the designable domain and the non-designable domain 18 are re-defined in combination with the above assembly constraint; The optimization process of step S102 is performed again on the re-defined designable domain to perform the size optimization of the bolts 2, and finally the optimal arrangement scheme of the bolts 2 that meet the requirements of strength, stiffness, assembly feasibility and the like is obtained. The final optimization result is shown in Figure 6 .

[0043] The bolt 2 arrangement optimized in this embodiment makes the load distribution of the bolts 2 more uniform, and avoids stress concentration; meanwhile, the deformation of the sealing area is effectively controlled. As shown in Figure 7 , on the basis of not increasing the number of bolts 2, the deformation of the front-end sealing area 13 is reduced by 48% after optimization, and the deformation of the rear-end sealing area 14 is reduced by 62% after optimization. It can be seen that the risk of cold gas leakage is greatly reduced, and the sealing reliability and cooling efficiency of the nozzle heat insulation assembly are significantly improved.

[0044] The embodiments provided by the present application realize the precise optimization of the bolt 2 layout of the nozzle heat insulation assembly through the multi-stage design process combining topology optimization and assembly constraints. First, the initial layout of the bolts 2 is determined by establishing a simplified analysis model and using a multi-condition topology optimization method with weighted compliance response, to ensure the optimal overall stiffness of the assembly under multiple conditions. Then, the initial layout is optimized in detail based on the assembly constraints such as the paired arrangement of the bolts 2 at the positions of the hooks 5 and the bulges between the adjacent bolts 2, to further adjust the positions and number of the bolts 2. The finally obtained optimal layout of the bolts 2 not only makes the load distribution more uniform and effectively avoids stress concentration, but also significantly reduces the deformation of the sealing area, such as the deformation of the front-end sealing area 13 is reduced by 48% and the deformation of the rear-end sealing area 14 is reduced by 62%. Without increasing the number of bolts 2, the sealing reliability and cooling efficiency of the heat insulation assembly are greatly improved, which provides an efficient and engineering practical solution for the structural design of the nozzle heat insulation system.

[0045] The method also has the following advantages: high calculation efficiency: by reasonably simplifying the modeling of the impact plate, the bolt 2 and the heat insulation layer, the model complexity is significantly reduced, and the topological optimization calculation efficiency is improved; Design is more optimal: a multi-working-condition topological optimization method based on weighted flexibility response is adopted, the relative density of the bolt 2 unit is taken as a design variable, under the premise of strictly meeting the bolt 2 strength (maximum tensile load) and the heat insulation layer stiffness (maximum displacement) constraints, the minimum of the overall weighted flexibility of the heat insulation assembly is realized, which is equivalent to optimizing the force transmission path of the structure, so that the load transmission is more direct and efficient; Consideration: innovatively adopt two-stage optimization strategy, first obtain the optimal force transmission bolt 2 layout sketch through topological optimization, then combine specific assembly constraints for detail optimization, ensure that the design scheme has optimal performance and engineering practicability.

[0046] The above is only a specific embodiment of the present application, but the protection scope of the present application is not limited to this, any person skilled in the art can easily think of changes or replacements within the technical range disclosed in the present application, which should be covered in the protection scope of the present application. Therefore, the protection scope of the present application should be subject to the protection scope of the claims.

Claims

1. A method for designing a bolt arrangement of a nozzle insulation assembly based on topology optimization, characterized in that, The application relates to a method for determining the optimal layout of bolts in a thermal insulation assembly. The method comprises the following steps: establishing a simplified analysis model for the thermal insulation assembly, the thermal insulation assembly comprising an impact layer, a bulge layer and an air film layer, the bulge layer and the air film layer being welded to form a thermal insulation layer, and bolts being welded on the bulge layer and used for connecting the impact layer and hooks on the impact layer, the bolts being simplified as beam elements; determining an initial layout of the bolts in the simplified analysis model by using a multi-working-condition topology optimization method based on weighted flexibility response; 2. The method of claim 1, wherein, performing detailed optimization based on assembly constraints on the initial layout of the bolts to obtain an optimal layout of the bolts. The step of establishing the simplified analysis model for the thermal insulation assembly comprises the following steps: simplifying the impact plate as a constrained position; 3. The method of claim 1, wherein, simulating the thermal insulation layer by using a shell element. The step of determining the initial layout of the bolts in the simplified analysis model by using the multi-working-condition topology optimization method based on the weighted flexibility response comprises the following steps: defining a designable domain, and taking the relative density of the beam element in the designable domain as an optimization design variable; 4. The method of claim 3, wherein, topology optimizing the relative density of the beam element in the designable domain under optimization constraint conditions and taking the minimum weighted flexibility of the thermal insulation assembly under all examination working conditions as an optimization target to obtain the initial layout of the bolts. The step of defining the designable domain comprises the following steps:

5. The method of claim 3, wherein, defining the area between the bulges which cannot be arranged with the bolts and the area between the bulges which must be arranged with the bolts as non-designable domains according to the function and assembly requirement of the thermal insulation assembly, and taking the remaining area between the bulges as the designable domain. The step of taking the relative density of the beam element in the designable domain as the optimization design variable comprises the following steps: establishing a mapping relationship between the design variable and the material attribute based on a material interpolation model, and making the relative density of the beam element tend to 0 or 1 by controlling the density and stiffness relationship of the beam element; 6. The method of claim 3, wherein, when the relative density of the beam element tends to 1, it indicates that the bolt needs to be arranged at the position; and when the relative density of the beam element tends to 0, it indicates that the bolt does not need to be arranged at the position. The optimization constraint conditions comprise the following steps: ≤ where F z is the maximum tensile load, d is the bolt diameter, is the yield strength limit of the material; the maximum tensile load borne by a single bolt satisfies the following relationship: the maximum displacement of the thermal insulation layer does not exceed a design allowable value; 7. The method of claim 3, wherein, symmetrical constraint conditions are applied. Calculate the initial compliance of the insulation assembly under each test condition i and the total tensile load on all bolts ; calculating the total tensile load for each test condition i the total tensile load for the preset reference condition the ratio K Fi ; Based on the ratio K Fi The initial compliance of each test condition i The modified compliance C of each test condition i is obtained by performing the modification mi ; Determine the compliance weight coefficient of each test condition i ; Based on the corrected compliance C mi and the compliance weight coefficient The relative density of the beam unit in the designable domain is topologically optimized to minimize the weighted compliance of the thermal insulation assembly under all test conditions.

8. The method of claim 7, wherein, The modified compliance C mi The expression for the modified compliance C is: 。 9. The method of claim 7, wherein, The step of topology optimizing the relative density of the beam element in the designable domain under the optimization constraint conditions and taking the minimum weighted flexibility of the thermal insulation assembly under all examination working conditions as the optimization target comprises the following steps: ， where C w is the weighted compliance.

10. The method of claim 5, wherein, the expression of the weighted flexibility is as follows: The step of performing detailed optimization based on assembly constraints on the initial layout of the bolts to obtain the optimal layout of the bolts comprises the following steps: identifying the area in which the relative density of the beam element tends to 1 in the initial layout of the bolts as bolt position candidate points; determining assembly constraints, the assembly constraints including that the bolts at the hook positions need to appear in pairs, and the adjacent bolts are separated by one column of bulges to ensure assembly space; redistributing the designable domain and the non-designable domain based on the assembly constraints for the bolt position candidate points; topology optimizing the designable domain after the redistribution to obtain the optimal layout of the bolts which satisfies the strength, stiffness and assembly feasibility.

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