Design method of lightweight high-rigid bearing superstructure frame for space heat dissipation system

Abstract

A design method of lightweight high-stiffness bearing superstructure frame for space heat dissipation system is proposed. Firstly, the initial geometric model of bearing frame is established according to the structure size and assembly requirements of heat dissipation module, and the assembly connection hole and its surrounding area are set as non-design space. Under the given boundary conditions and load conditions, the topology optimization algorithm based on SIMP method is introduced to obtain the optimal material distribution form with minimum mass as the objective function and stress and safety factor constraints. Then, the topology optimization results are reconstructed by lattice geometry to form a regular and manufacturable bearing lattice superstructure. Finally, the integrated forming of the structure is realized by metal additive manufacturing technology.

Description

Technical Field

[0001] This invention relates to a design method for a lightweight, high-rigidity, superstructure frame for a space heat dissipation system, belonging to the technical field of lightweight load-bearing structure design and thermal management system integration. Background Technology

[0002] With the deepening of human space activities such as deep space exploration and manned spaceflight, the scientific research and engineering tasks undertaken by spacecraft are becoming increasingly complex. To achieve more powerful high-capacity communication, high-resolution detection, and autonomous intelligent computing capabilities, the integration and computational load of spacecraft electronic equipment are continuously increasing, leading to a continuous increase in power density and a sharp rise in internal waste heat. Against this backdrop, the space heat dissipation system, responsible for the rational organization of the transfer, utilization, and dissipation of heat inside and outside the spacecraft, ensuring that its temperature and humidity environment remains within a controllable range, has become one of the key subsystems for maintaining the long-term stable operation of spacecraft in orbit.

[0003] In engineering implementation, the heat dissipation system requires installation and fixation via a specialized support frame. This frame not only serves as the main structural element ensuring stable operation of the system under harsh mechanical conditions but also constitutes a crucial functional carrier for the flow of heat dissipation media and convective heat transfer. Therefore, the design of the space heat dissipation system frame must simultaneously meet several key requirements: first, it must possess sufficient rigidity and strength to withstand the complex loads during launch and on-orbit phases; second, it must achieve extreme lightweighting to improve spacecraft launch efficiency and endurance; and third, it must form a highly porosity, interconnected space within the structure to serve as an efficient heat exchange channel, ensuring heat dissipation performance.

[0004] Currently, traditional heat dissipation systems commonly used in engineering often employ solid plates or simple perforated structures as support frames. While these structures can guarantee basic mechanical properties, they suffer from low material utilization, leading to redundant structural mass. Furthermore, the dense solid form hinders internal airflow and cooling medium distribution, severely limiting the overall system heat dissipation efficiency and failing to meet the combined requirements of lightweight design and efficient heat dissipation. In recent years, high-porosity lattice structures have gained increasing attention due to their excellent specific strength, specific stiffness, and good thermal conductivity and convection characteristics. However, existing research on lattice structures largely focuses on idealized unit structures or single mechanical property analysis, lacking system design methods tailored to specific engineering applications, particularly in areas such as complex assembly constraints, load-bearing path control, and manufacturing feasibility. Summary of the Invention

[0005] The technical problem solved by this invention is to address the design defects of traditional load-bearing structures in the existing technology by proposing a design method for a lightweight, high-rigidity load-bearing superstructure frame for a space heat dissipation system.

[0006] The present invention solves the above-mentioned technical problem through the following technical solution: A design method for a lightweight, high-rigidity load-bearing superstructure frame for a space heat dissipation system includes: The actual assembly requirements of the space heat dissipation system are determined to establish the initial geometric model of the load-bearing superstructure frame; The initial geometric model is spatially divided to determine the non-design space and the designable space; Apply preset boundary conditions and load conditions within the designable space; A topology optimization algorithm for the pre-defined designable space is used to perform topology optimization design on the designable space with the goal of minimizing structural mass, and the topology optimization results are obtained. The topology optimization results are converged, and the topology optimization results are iteratively updated based on the convergence results to obtain the topology optimization results under convergence conditions. The topology optimization results under convergence are reconstructed into lattice structures, and the safety factor of the obtained lattice structures is checked. The lattice structure that has passed the safety factor check is integrally formed by metal additive manufacturing to obtain the corresponding load-bearing superstructure frame. After processing, the finished load-bearing superstructure frame is obtained.

[0007] The actual assembly requirements of the space heat dissipation are used to determine the structural composition of the space heat dissipation system. The space heat dissipation system includes a heat dissipation base plate, fluid channel pipes and a square frame. The heat dissipation base plate and the square frame are rectangular plates with matching edges. The fluid channel pipes are evenly arranged on the surface of the heat dissipation base plate in the form of paper clips. The heat dissipation base plate is provided with connecting bosses on its edges. The heat dissipation base plate is screwed to the inside of the square frame through the connecting bosses.

[0008] The initial geometric model of the load-bearing superstructure frame is designed as a rectangular ring structure according to the specific shape of the space heat dissipation system. The upper surface of the four sides of the load-bearing superstructure frame is evenly arranged with assembly connection holes for connecting to the lower edge of the heat dissipation substrate by bolts. The inner side of the four sides of the load-bearing superstructure frame is provided with transverse through assembly connection holes for connecting adjacent load-bearing superstructure frames.

[0009] The initial geometric model is divided into non-design space and designable space. The assembly connection holes, the transverse series assembly connection holes and the surrounding area of ​​each connection hole are used as non-design space, and the remaining areas are used as designable space. The structural mass of the designable space is minimized through topology optimization design.

[0010] The boundary conditions are fixed constraints on the load-bearing superstructure frame. The fixed constraints on the load-bearing superstructure frame are used to fix the four corner positions of the load-bearing superstructure frame. The load condition is the equivalent load under the working state of the heat dissipation system. The equivalent load is the concentrated load borne by the midpoints of the four sides of the load-bearing superstructure frame.

[0011] The method for performing topology optimization design on the designable space and obtaining the topology optimization results is as follows: A topology optimization algorithm based on solid isotropic material penalty is introduced within the design space. The optimization objective function is to minimize the structural mass. Stress constraints and safety factor constraints are set simultaneously to formulate the topology optimization design principle. When the topology optimization result output by the objective function satisfies the topology optimization design principle, the current topology optimization result is output. The topology optimization design principle is that the maximum Mises equivalent stress of the load-bearing superstructure does not exceed the material yield strength and the overall safety factor is not less than the preset value. The topology optimization design principle also includes constraints on the metal additive manufacturing process, which limits the range of crossbar length, diagonal bar length, and bar diameter of the load-bearing superstructure frame.

[0012] The designable space discretization process is as follows: N A finite number of units, for each unit i Define a relative density variable:

[0013] In the formula Indicates empty material. Represents physical materials, Represents approximately empty material; The objective function to be optimized is:

[0014] The mathematical model for stress constraints and safety factor constraints is as follows:

[0015] In the formula, Let be the Mises stress of the i-th element. .

[0016] The topology optimization result under the convergence condition simultaneously satisfies the stress constraints and safety factor constraints of the topology optimization design principle, as well as the constraints of the metal additive manufacturing process. The method for lattice reconstruction of the topology optimization result is as follows: The topology optimization results are converted into the optimal material distribution form of the load-bearing superstructure frame and decomposed into a lattice structure formed by the periodic connection of each spatial member. Each member in the lattice structure is limited to a preset range, and the length of each member is designed according to the load-bearing requirements to ensure that the lattice structure meets the requirements of load-bearing performance and manufacturing process constraints.

[0017] The safety factor of the lattice structure is checked, and a lattice cloud map is obtained. When the minimum safety factor of the lattice cloud map meets the preset check requirements, metal additive manufacturing is carried out according to the lattice structure to form an integral load-bearing superstructure frame. When the minimum safety factor of the lattice cloud map does not meet the preset check requirements, the topology optimization of the designable space corresponding to the current lattice structure is carried out again until the minimum safety factor of the updated lattice cloud map meets the preset check requirements.

[0018] The process of the integrally formed load-bearing superstructure frame includes: surface quality treatment and mechanical property inspection; the integrally formed metal additive manufacturing process uses selective laser melting, electron beam melting or equivalent metal 3D printing.

[0019] The advantages of this invention compared to the prior art are: (1) The present invention provides a design method for a lightweight and high-rigidity load-bearing superstructure frame for a space heat dissipation system. It gives the load-bearing superstructure frame and its design and manufacturing method. By combining topology optimization and lattice reconstruction, it achieves high porosity and lightweight design of the structure while meeting the requirements of load bearing, safety and assembly, and improves the overall performance of the heat dissipation system. It can obtain the optimal material distribution by introducing a topology optimization algorithm based on the SIMP method, with the minimum mass as the objective function, and applying stress and safety factor constraints. It also gives the lattice geometric reconstruction results, and realizes a regular and manufacturable load-bearing lattice superstructure product design scheme. (2) This invention significantly reduces structural mass while ensuring load-bearing capacity, and can form a reasonable and clear force transmission path to improve the overall stiffness and stability of the structure. At the same time, it realizes air circulation and heat exchange through high porosity lattice structure design, improves heat dissipation efficiency, adapts to additive manufacturing process by utilizing structural form, has high forming accuracy and good assembly reliability, and the overall design is suitable for engineering applications of various thermal management systems and lightweight load-bearing structures. Attached Figure Description

[0020] Figure 1 Flowchart of the optimized design of the lightweight, high-rigidity, load-bearing superstructure frame for the space heat dissipation system provided by this invention; Figure 2 A schematic diagram of the heat dissipation system and its load-bearing frame structure provided by the present invention; Figure 3 This is a schematic diagram illustrating the division of design space and non-design space provided by the present invention; Figure 4 This is a schematic diagram of the topology optimization results of the load-bearing lattice superstructure frame provided by the present invention; Figure 5 Safety factor cloud diagram of the load-bearing lattice superstructure frame provided by the present invention; Figure 6This is a schematic diagram of the heat dissipation system and the load-bearing lattice superstructure frame provided by the present invention. Detailed Implementation

[0021] A design method for a lightweight, high-rigidity load-bearing superstructure frame for a space heat dissipation system is proposed. First, an initial geometric model of the load-bearing frame is established based on the structural dimensions and assembly requirements of the heat dissipation module, and the assembly connection holes and their surrounding areas are designated as non-design spaces. Under given boundary conditions and load conditions, a topology optimization algorithm based on the SIMP method is introduced, with minimum mass as the objective function, and stress and safety factor constraints are applied to obtain the optimal material distribution. Subsequently, the topology optimization results are subjected to lattice-based geometric reconstruction to form a regular, manufacturable load-bearing lattice superstructure. Finally, metal additive manufacturing technology is used to achieve the integrated forming of the structure.

[0022] The design method for load-bearing superstructure frames includes the following specific design steps: The actual assembly requirements of the space heat dissipation system are determined to establish the initial geometric model of the load-bearing superstructure frame; The initial geometric model is spatially divided to determine the non-design space and the designable space; Apply preset boundary conditions and load conditions within the designable space; A topology optimization algorithm for the pre-defined designable space is used to perform topology optimization design on the designable space with the goal of minimizing structural mass, and the topology optimization results are obtained. The topology optimization results are converged, and the topology optimization results are iteratively updated based on the convergence results to obtain the topology optimization results under convergence conditions. The topology optimization results under convergence are reconstructed into lattice structures, and the safety factor of the obtained lattice structures is checked. The lattice structure that has passed the safety factor check is integrally formed by metal additive manufacturing to obtain the corresponding load-bearing superstructure frame. After processing, the finished load-bearing superstructure frame is obtained.

[0023] The actual assembly requirements of the space heat dissipation system are used to determine the structural composition of the space heat dissipation system. The space heat dissipation system includes a heat dissipation base plate, fluid channel pipes and a square frame. The heat dissipation base plate and the square frame are rectangular plates with matching edges. The fluid channel pipes are evenly arranged on the surface of the heat dissipation base plate in the form of paper clips. The heat dissipation base plate is provided with connecting bosses on its edges. The heat dissipation base plate is screwed to the inside of the square frame through the connecting bosses.

[0024] The initial geometric model of the load-bearing superstructure frame is designed as a rectangular ring structure according to the specific shape of the space heat dissipation system. The upper surface of the four sides of the load-bearing superstructure frame is evenly arranged with assembly connection holes for connecting to the lower edge of the heat dissipation base plate by bolts. The inner side of the four sides of the load-bearing superstructure frame is provided with transverse through assembly connection holes for connecting adjacent load-bearing superstructure frames.

[0025] The initial geometric model is divided into non-design space and designable space. The assembly connection holes, the transverse series assembly connection holes and the surrounding area of ​​each connection hole are used as non-design space, and the remaining areas are used as designable space. The structural mass of the designable space is minimized through topology optimization design.

[0026] The boundary conditions are fixed constraints on the load-bearing superstructure frame. The fixed constraints on the load-bearing superstructure frame are used to fix the four corner positions of the load-bearing superstructure frame. The load conditions are the equivalent loads under the working state of the heat dissipation system. The equivalent loads are the concentrated loads borne by the midpoints of the four sides of the load-bearing superstructure frame.

[0027] The method for performing topology optimization design on the designable space and obtaining the topology optimization results is as follows: A topology optimization algorithm based on solid isotropic material penalty is introduced within the design space. The optimization objective function is to minimize the structural mass. Stress constraints and safety factor constraints are set simultaneously to formulate the topology optimization design principle. When the topology optimization result output by the objective function satisfies the topology optimization design principle, the current topology optimization result is output. The topology optimization design principle is that the maximum Mises equivalent stress of the load-bearing superstructure does not exceed the material yield strength and the overall safety factor is not less than the preset value. The topology optimization design principle also includes constraints on the metal additive manufacturing process, which limits the range of crossbar length, diagonal bar length, and bar diameter of the load-bearing superstructure frame.

[0028] Spatial discretization can be designed as N A finite number of units, for each unit i Define a relative density variable:

[0029] In the formula Indicates empty material. Represents physical materials, Represents approximately empty material; The objective function to be optimized is:

[0030] The mathematical model for stress constraints and safety factor constraints is as follows:

[0031] In the formula, Let be the Mises stress of the i-th element. .

[0032] The topology optimization results under convergence simultaneously satisfy the stress constraints and safety factor constraints of the topology optimization design principles, as well as the constraints of the metal additive manufacturing process. The method for lattice reconstruction of the topology optimization results is as follows: The topology optimization results are converted into the optimal material distribution form of the load-bearing superstructure frame and decomposed into a lattice structure formed by the periodic connection of each spatial member. Each member in the lattice structure is limited to a preset range, and the length of each member is designed according to the load-bearing requirements to ensure that the lattice structure meets the requirements of load-bearing performance and manufacturing process constraints.

[0033] The safety factor of the lattice structure is checked, and a lattice cloud map is obtained. When the minimum safety factor of the lattice cloud map meets the preset check requirements, metal additive manufacturing is carried out according to the lattice structure to form an integral load-bearing superstructure frame. When the minimum safety factor of the lattice cloud map does not meet the preset check requirements, the topology optimization of the designable space corresponding to the current lattice structure is carried out again until the minimum safety factor of the updated lattice cloud map meets the preset check requirements.

[0034] The process of the integral molding design load-bearing superstructure frame includes: surface quality treatment and mechanical property inspection; the integral molding metal additive manufacturing process selects selective laser melting, electron beam melting or equivalent metal 3D printing process.

[0035] The following description, in conjunction with the accompanying drawings and preferred embodiments, provides further details: In the current embodiment, the design process is as follows: Figure 1 As shown, firstly, an initial geometric model of the load-bearing frame is established based on the structural dimensions and assembly requirements of the heat dissipation module, and the assembly connection holes and their surrounding areas are set as non-design spaces. Under given boundary conditions and load conditions, a topology optimization algorithm based on the SIMP method is introduced, with minimum mass as the objective function, and stress and safety factor constraints are applied to obtain the optimal material distribution. Subsequently, the topology optimization results are subjected to lattice-based geometric reconstruction to form a regular, manufacturable load-bearing lattice superstructure. Finally, metal additive manufacturing technology is used to achieve the integrated forming of the structure.

[0036] like Figure 2 As shown, the space heat dissipation system 2 consists of a heat dissipation substrate 21 and a fluid channel pipe 22. The edge of the heat dissipation substrate has 12 sets of connecting bosses with through holes, which are fastened with bolts to achieve a detachable rigid connection with the square frame 1.

[0037] First, an initial geometric model of the load-bearing frame is established based on the actual assembly requirements of the heat dissipation module. For example... Figure 3As shown, the load-bearing frame is a rectangular ring structure with an outer side length of 340 mm, an inner side length of 320 mm, and a thickness of 10 mm. Three assembly connection holes are evenly distributed on the four sides of the load-bearing frame for reliable connection to the heat dissipation base plate 21 via bolts. Additionally, two transverse assembly connection holes are provided for direct bolt connection of multiple load-bearing frames.

[0038] Secondly, based on the assembly function requirements, all assembly connection holes and their surrounding areas are divided into non-design spaces to ensure the structural integrity and assembly accuracy of the connection areas; the remaining areas are divided into designable spaces for topology optimization design.

[0039] Then, boundary conditions and load cases are applied to the load-bearing frame. The boundary conditions are set as fixed constraints at the four corners of the load-bearing frame, and the load cases are concentrated loads of 1.0N borne by the midpoints of the four sides of the load-bearing frame.

[0040] Based on this, a topology optimization algorithm based on the Solid Isotropic Material Penalty (SIMP) method is introduced within the designable space. The objective function is to minimize the structural mass, while simultaneously setting stress constraints and safety factor constraints. The algorithm requires that the maximum Mises equivalent stress of the structure does not exceed the material yield strength, and the overall safety factor is not less than 1.2. The design domain is discretized into... N A finite number of units, for each unit i Define a relative density variable:

[0041] In the formula (To avoid numerical singularity) Represents physical materials, This represents approximately empty material.

[0042] The mathematical model for the objective function (mass minimization) is as follows:

[0043] The mathematical model for stress constraint (safety factor) is as follows:

[0044] in Let be the Mises stress of the i-th element. .

[0045] The equivalent material density of the i-th element and the geometric volume of the i-th element.

[0046] The mathematical model for constraining the geometric parameters of the structure based on the metal additive manufacturing process is as follows: Length of crossbar:

[0047] Length of diagonal brace:

[0048] Rod diameter range:

[0049] The optimal material distribution of the load-bearing frame was obtained through multiple iterative calculations.

[0050] Subsequently, the topology optimization results were subjected to lattice-based geometric reconstruction, transforming the continuous material distribution into a lattice structure formed by the periodic connection of multiple spatial rods. The rod diameters of the lattice structure were limited to the range of 0.4–0.8 mm, and the rod lengths were controlled according to the structural dimensions and load-bearing requirements. This ensured that the resulting lattice structure met both mechanical performance requirements and manufacturing process constraints. The final optimization result is as follows: Figure 4 As shown. Its safety factor is checked, and the cloud map is as follows. Figure 5 As shown, its minimum safety factor is greater than or equal to 11.9. It achieves a weight reduction of over 30% compared to traditional structures, and the first three fundamental frequencies are improved by 196%, 141%, and 136%, respectively. Finally, the load-bearing frame after lattice reconstruction is integrally formed using metal additive manufacturing technology, and the surface quality and overall mechanical properties of the structure are improved through necessary post-processing, ultimately resulting in a load-bearing lattice superstructure for heat dissipation systems.

[0051] Furthermore, the load-bearing lattice superstructure is a frame structure used to support the heat dissipation module, including an assembly connection area and a lattice load-bearing area. The assembly connection area retains a complete solid structure as a non-design space, while the remaining areas are high-porosity lattice structures. The lattice structure is formed by periodically connecting multiple spatial rods, which is used to reduce the overall mass and enhance the heat exchange capacity while ensuring structural strength.

[0052] In this embodiment, the simplified processing flow includes: (1) Establish the initial geometric model of the heat dissipation system support frame, and clarify the external dimensions, thickness and assembly connection hole positions; (2) Define the connection hole and its surrounding area as non-design space, and the remaining area as designable space; (3) Apply boundary conditions and load conditions within the designable space. The boundary conditions are frame fixation constraints, and the loads are equivalent loads under the working state of the heat dissipation system. (4) A topology optimization algorithm based on the penalty method for solid isotropic materials is adopted, with minimizing the structural mass as the optimization objective, and stress and safety factor constraints are introduced; (5) The topology optimization results are reconstructed into a lattice to form a lattice superstructure that satisfies the length, diameter and manufacturing constraints of the rods; (6) The lattice superstructure is manufactured in an integrated manner using metal additive manufacturing process to obtain a lightweight and high-rigidity superstructure frame for the space heat dissipation system.

[0053] The topology optimization algorithm described in step (4) adopts the SIMP method, which transforms the discrete material distribution problem into a continuous optimization problem by introducing the relative density variable of the elements.

[0054] The stress constraint in step (4) is based on the condition that the maximum equivalent stress of the structure does not exceed the yield strength of the material, and the overall safety factor is not less than 1.2.

[0055] In step (5), the geometric parameters of the lattice members are satisfied as follows: the minimum member diameter is 0.4 to 0.8 mm, and the member length is limited to a preset range according to the load-bearing requirements.

[0056] The overall porosity of the lattice superstructure is greater than 80%.

[0057] The metal additive manufacturing process described in step (6) is selective laser melting, electron beam melting, or an equivalent metal 3D printing process, to obtain, for example... Figure 6 The frame structure shown.

[0058] The specific implementation steps given in this embodiment can achieve a synergistic improvement in the lightweighting and heat dissipation performance of the load-bearing structure while ensuring structural safety and functional integrity.

[0059] Although the present invention has been disclosed above with reference to preferred embodiments, it is not intended to limit the present invention. Any person skilled in the art can make possible changes and modifications to the technical solutions of the present invention by utilizing the methods and techniques disclosed above without departing from the spirit and scope of the present invention. Therefore, any simple modifications, equivalent changes and alterations made to the above embodiments based on the technical essence of the present invention without departing from the content of the technical solutions of the present invention shall fall within the protection scope of the technical solutions of the present invention.

[0060] The contents not described in detail in this specification are common knowledge to those skilled in the art.

Claims

1. A design method for a lightweight, high-rigidity, load-bearing superstructure frame for a space heat dissipation system, characterized in that... include: The actual assembly requirements of the space heat dissipation system are determined to establish the initial geometric model of the load-bearing superstructure frame; The initial geometric model is spatially divided to determine the non-design space and the designable space; Apply preset boundary conditions and load conditions within the designable space; A topology optimization algorithm for the pre-defined designable space is used to perform topology optimization design on the designable space with the goal of minimizing structural mass, and the topology optimization results are obtained. The topology optimization results are converged, and the topology optimization results are iteratively updated based on the convergence results to obtain the topology optimization results under convergence conditions. The topology optimization results under convergence are reconstructed into lattice structures, and the safety factor of the obtained lattice structures is checked. The lattice structure that has passed the safety factor check is integrally formed by metal additive manufacturing to obtain the corresponding load-bearing superstructure frame. After processing, the finished load-bearing superstructure frame is obtained.

2. The design method for a lightweight, high-rigidity, superstructure frame for a space heat dissipation system according to claim 1, characterized in that: The actual assembly requirements of the space heat dissipation are used to determine the structural composition of the space heat dissipation system. The space heat dissipation system includes a heat dissipation base plate, fluid channel pipes and a square frame. The heat dissipation base plate and the square frame are rectangular plates with matching edges. The fluid channel pipes are evenly arranged on the surface of the heat dissipation base plate in the form of paper clips. The heat dissipation base plate is provided with connecting bosses on its edges. The heat dissipation base plate is screwed to the inside of the square frame through the connecting bosses.

3. The design method for a lightweight, high-rigidity, superstructure frame for a space heat dissipation system according to claim 2, characterized in that: The initial geometric model of the load-bearing superstructure frame is designed as a rectangular ring structure according to the specific shape of the space heat dissipation system. The upper surface of the four sides of the load-bearing superstructure frame is evenly arranged with assembly connection holes for connecting to the lower edge of the heat dissipation substrate by bolts. The inner side of the four sides of the load-bearing superstructure frame is provided with transverse through assembly connection holes for connecting adjacent load-bearing superstructure frames.

4. The design method for a lightweight, high-rigidity load-bearing superstructure frame for a space heat dissipation system according to claim 3, characterized in that: The initial geometric model is divided into non-design space and designable space. The assembly connection holes, the transverse series assembly connection holes and the surrounding area of ​​each connection hole are used as non-design space, and the remaining areas are used as designable space. The structural mass of the designable space is minimized through topology optimization design.

5. The design method for a lightweight, high-rigidity, superstructure frame for a space heat dissipation system according to claim 4, characterized in that: The boundary conditions are fixed constraints on the load-bearing superstructure frame. The fixed constraints on the load-bearing superstructure frame are used to fix the four corner positions of the load-bearing superstructure frame. The load condition is the equivalent load under the working state of the heat dissipation system. The equivalent load is the concentrated load borne by the midpoints of the four sides of the load-bearing superstructure frame.

6. The design method for a lightweight, high-rigidity load-bearing superstructure frame for a space heat dissipation system according to claim 4, characterized in that: The method for performing topology optimization design on the designable space and obtaining the topology optimization results is as follows: A topology optimization algorithm based on solid isotropic material penalty is introduced within the design space. The optimization objective function is to minimize the structural mass. Stress constraints and safety factor constraints are set simultaneously to formulate the topology optimization design principle. When the topology optimization result output by the objective function satisfies the topology optimization design principle, the current topology optimization result is output. The topology optimization design principle is that the maximum Mises equivalent stress of the load-bearing superstructure does not exceed the material yield strength and the overall safety factor is not less than the preset value. The topology optimization design principle also includes constraints on the metal additive manufacturing process, which limits the range of crossbar length, diagonal bar length, and bar diameter of the load-bearing superstructure frame.

7. The design method for a lightweight, high-rigidity, superstructure frame for a space heat dissipation system according to claim 6, characterized in that: The designable space discretization process is as follows: N A finite number of units, for each unit i Define a relative density variable: In the formula Indicates empty material. Represents physical materials, Represents approximately empty material; Optimize objective function for: The mathematical model for stress constraints and safety factor constraints is as follows: In the formula, Let be the Mises stress of the i-th element. , The equivalent material density of the i-th element and the geometric volume of the i-th element.

8. The design method for a lightweight, high-rigidity, superstructure frame for a space heat dissipation system according to claim 6, characterized in that: The topology optimization result under the convergence condition simultaneously satisfies the stress constraints and safety factor constraints of the topology optimization design principle, as well as the constraints of the metal additive manufacturing process. The method for lattice reconstruction of the topology optimization result is as follows: The topology optimization results are converted into the optimal material distribution form of the load-bearing superstructure frame and decomposed into a lattice structure formed by the periodic connection of each spatial member. Each member in the lattice structure is limited to a preset range, and the length of each member is designed according to the load-bearing requirements to ensure that the lattice structure meets the requirements of load-bearing performance and manufacturing process constraints.

9. The design method for a lightweight, high-rigidity, superstructure frame for a space heat dissipation system according to claim 8, characterized in that: The safety factor of the lattice structure is checked and the lattice cloud map is obtained. When the minimum safety factor of the lattice cloud map meets the preset check requirements, metal additive manufacturing is carried out according to the lattice structure to form an integral load-bearing superstructure frame. If the minimum safety factor of the dot matrix cloud does not meet the preset verification requirements, the topology optimization of the designable space corresponding to the current dot matrix structure is carried out again until the minimum safety factor of the updated dot matrix cloud meets the preset verification requirements.

10. The design method for a lightweight, high-rigidity load-bearing superstructure frame for a space heat dissipation system according to claim 9, characterized in that: The process of the integrally formed load-bearing superstructure frame includes: surface quality treatment and mechanical property inspection; the integrally formed metal additive manufacturing process uses selective laser melting, electron beam melting or equivalent metal 3D printing.

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