A multi-physical field driven mirror bearing heat conduction integrated collaborative design method

Abstract

The application discloses a kind of multi-physical field driven mirror bearing heat conduction integrated collaborative design method, solve the existing unmanned aerial vehicle airborne optical system mirror, under the condition that lack of active thermal control device provides complex force and heat load, cannot have high stiffness and high thermal conductivity performance, leading to mirror deformation, surface shape precision significantly reduced technical problem;The application selects TPMS Gyroid cell as mirror internal cell, eliminates local stress concentration, ensures the smooth transmission of force and heat load in complex three-dimensional space;Also proposed a multi-physical composite driving mechanism, by extracting strain energy density field and heat flux density field weighted fusion, with the spatial distribution of relative density of TPMS Gyroid cell establishes mapping relationship, so that in the key area of strain energy density and heat flux density is high, automatically increase material, realize the high stiffness of mirror against gravity deformation, so that heat can be evenly spread in mirror body, inhibit the mirror thermal deformation under complex force and heat environment.

Description

Technical Field

[0001] This invention relates to an optimization method for optical remote sensor components, specifically to a multi-physics-driven integrated design method for heat conduction and support of a reflector. Background Technology

[0002] Miniaturized drones fly at altitudes ranging from hundreds to thousands of meters. Gravitational loads can cause the mirrors of the drone's onboard optical system to bend and deform, while changes in ambient temperature can cause thermal deformation of the mirrors. The combined effect of these two factors significantly reduces the surface accuracy of the mirrors, greatly affecting the imaging quality of the onboard optical system.

[0003] Traditional UAV onboard optical system mirror structure design relies on theoretical analysis and empirical design, and is also limited by manufacturing processes, often employing an open-back weight reduction structure. Lightweighting is achieved by arranging triangular, circular, or honeycomb-shaped open structures on the back of the mirror. However, while such macroscopic structures achieve high weight reduction rates, they are highly susceptible to physical bottlenecks such as sudden drops in structural stiffness, localized stress concentration, and obstructed heat transfer paths.

[0004] Topology optimization of the aforementioned reflectors is an emerging design method that can produce structures with superior performance. However, traditional continuum topology optimization methods struggle to converge under complex force-thermal coupling boundary conditions. Existing research primarily focuses on the stiffness and lightweighting of the reflector structure as optimization objectives, with limited consideration for the temperature gradient caused by environmental thermal loads.

[0005] Limited by factors such as size, power consumption, weight, and cost, miniaturized UAV onboard optical systems typically lack sophisticated active thermal control devices. Therefore, the reflector itself not only needs high rigidity to resist deformation caused by its own weight, but also must possess excellent thermal conductivity to rapidly and uniformly dissipate internal temperature under high-dynamic heat flow, actively mitigating thermal deformation caused by temperature gradients. Current research still has shortcomings in the integrated design of reflectors that support thermal conductivity, urgently requiring a new design method to improve reflector performance. Summary of the Invention

[0006] The purpose of this invention is to solve the technical problem that existing UAV airborne optical system reflectors, under the conditions of lack of active thermal control devices and complex force and thermal loads, cannot simultaneously possess high rigidity and high thermal conductivity, resulting in large reflector deformation and a significant decrease in surface accuracy. The invention provides a multi-physics field driven reflector load-bearing and thermal conductivity integrated collaborative design method.

[0007] To achieve the above objectives, the technical solution provided by this invention is as follows:

[0008] A multi-physics-driven integrated design method for reflector-supported thermal conductivity is characterized by the following steps:

[0009] Step 1: Using the optical design results as input, determine the basic structural parameters of the reflector, and construct an initial model of the reflector in conjunction with the operating conditions. The initial model of the reflector includes an internal design domain and an external solid region.

[0010] Step 2: Apply fixed constraints and mechanical loads to the initial model of the reflector and perform static finite element analysis to extract the strain energy density values ​​of each spatial node in the internal design domain, and generate the strain energy density field in the three-dimensional coordinate system as the mechanical driving field.

[0011] Step 3: Apply thermal loads and thermal boundary conditions to the mirror surface and corresponding boundaries of the initial model of the reflector, perform thermodynamic finite element analysis, extract the heat flux density values ​​of each spatial node in the internal design domain, and generate a heat flux density field in a three-dimensional coordinate system as a thermal driving field.

[0012] Step 4: Perform linear normalization on the mechanical and thermal driving fields, and introduce structural stiffness weight coefficients and thermal conduction weight coefficients for weighted fusion to construct a multi-physics composite driving field;

[0013] Step 5: Select the TPMS Gyroid type unit cell as the internal unit cell of the initial model of the mirror, and establish a mapping function between the multiphysics composite driving field and the implicit function level set constant of the TPMS Gyroid type unit cell; obtain the multiphysics composite driving field value according to the mapping function, and obtain the variable density internal unit cell; when the multiphysics composite driving field value is greater than 0.2, the relative density of the TPMS Gyroid type unit cell is linearly mapped to the multiphysics composite driving field value; when it is less than or equal to 0.2, the multiphysics composite driving field value is assigned to 0.2;

[0014] Step 6: Perform Boolean operation conformal matching and fusion between the variable density internal cell and the external solid region to obtain the integrated reflector structure model that supports heat conduction; set the same fixed constraints and mechanical loads, thermal loads and thermal boundary conditions as the mechanical driving field and thermal driving field, perform finite element force-thermal coupling simulation analysis, extract the mirror nodal displacement data, remove rigid body displacement data, and calculate the surface accuracy by fitting a polynomial to determine whether the surface accuracy meets the preset requirements. If yes, proceed to step 7; otherwise, modify the structural stiffness weight coefficient and heat conduction weight coefficient, and return to step 4.

[0015] Step 7: Use the moving cube algorithm to convert the integrated heat-conducting reflector structure model into a three-dimensional surface mesh, and perform local mesh refinement and smoothing at the junction of the variable density internal cell and the external solid region to generate a processing model suitable for additive manufacturing process, and extract and output a standard three-dimensional additive manufacturing format file.

[0016] Furthermore, in step 1, the external solid area includes a mirror panel, a central light-transmitting hole, a back support hole, and an outer ring.

[0017] Furthermore, step 2 specifically involves:

[0018] A fixed constraint with full degrees of freedom is applied to the inner surface of the back support hole of the initial model of the reflector, and a mechanical load of one standard gravitational acceleration is applied to the initial model of the reflector along the optical axis.

[0019] A static finite element method is performed on the initial model of the reflector under applied mechanical load to extract the strain energy density values ​​of all spatial nodes in the internal design domain, generating a strain energy density field in a three-dimensional coordinate system. , as a driving force in mechanics;

[0020] The mechanical driving field is defined as:

[0021] ;

[0022] in, For mechanical driving field; () indicates the coordinate positions of the X-axis, Y-axis, and Z-axis in a three-dimensional coordinate system.

[0023] Furthermore, in step 3, the application of thermal loads and thermal boundary conditions to the mirror surface and corresponding boundaries of the initial model of the reflector is as follows:

[0024] A uniform heat source is applied to the mirror surface of the initial model of the reflector to simulate external thermal load;

[0025] Set the same air convection coefficient as the external environment of the mirror at the circumferential boundary of the initial model of the mirror;

[0026] The ambient temperature is set within the support hole on the back of the initial model of the reflector.

[0027] Further, in step 4, the expression for the multi-physics composite driving field is:

[0028] ;

[0029] ;

[0030] in, , ;

[0031] In the formula, It is a multi-physics composite driving field. This is the structural stiffness weighting coefficient. This is the heat conduction weighting coefficient. This is the normalized strain energy density field. The normalized heat flux density field, This represents the maximum value of the strain energy density field. This represents the minimum value of the strain energy density field. This represents the maximum value of the heat flux density field. q represents the minimum value of the heat flux density field, SED represents the strain energy density, and q represents the heat flux density.

[0032] Furthermore, in step 5, the implicit function level set constant of the TPMS Gyroid type unit cell is expressed as:

[0033]

[0034] in, For implicit functions of Gyroid-type unit cells; These represent the periodic dimensions of the TPMS Gyroid type unit cell along the X-axis, Y-axis, and Z-axis in a three-dimensional coordinate system, respectively. The implicit function level set constant of the TPMS Gyroid type unit cell; () indicates the coordinate positions of the X-axis, Y-axis, and Z-axis in a three-dimensional coordinate system.

[0035] Furthermore, in step 5, the mapping function expression between the multi-physics composite driving field and the implicit function level set constant of the TPMS Gyroid type unit cell is:

[0036] ;

[0037] f map For mapping functions, ( () represents the coordinate positions of the X, Y, and Z axes in a three-dimensional coordinate system. express The implicit function level set constant of the TPMS Gyroid type unit cell at that location.

[0038] Furthermore, in step 5, the mapping function is a linear mapping function.

[0039] Furthermore, in step 7, the standard 3D additive manufacturing format file is one of STL format, 3MF format, or AMF format.

[0040] Compared with the prior art, the present invention has the following beneficial technical effects:

[0041] 1. Breaking through the physical bottlenecks of traditional macroscopic lightweight structures, achieving continuity and efficiency in force and heat transfer paths: Addressing the technical problems of sudden stiffness drops, stress concentration, and obstructed heat transfer paths in traditional open-back structures under high lightweighting ratios, this invention introduces a TPMSGyroid-type unit cell with extremely high specific surface area, zero average curvature, and fully interconnected geometry as the internal unit cell of the reflector. This continuous curved surface structure fundamentally eliminates local stress concentration, ensuring smooth transfer of force and heat loads in complex three-dimensional space.

[0042] 2. Overcoming the deficiency of lack of active thermal control in small airborne systems, achieving excellent passive thermal management and high surface accuracy maintenance: Addressing the lack of precise active temperature control devices in miniaturized UAV airborne optical systems and the inadequacy of traditional topology optimization in rarely considering temperature gradient fields, this invention proposes a multi-physics composite driving mechanism. By extracting and weighting the strain energy density field and heat flux density field, a mapping relationship is established with the spatial distribution of the relative density of the TPMS Gyroid-type cell, enabling automatic material addition in key regions with high strain energy density and high heat flux density. This method not only ensures the high stiffness of the mirror against deformation due to its own weight but also allows heat to diffuse uniformly within the mirror body, actively weakening the temperature gradient and fundamentally suppressing thermal deformation of the mirror under complex mechanical and thermal environments.

[0043] 3. Overcomes the problem of easy divergence in traditional multiphysics topology optimization, and improves design efficiency and manufacturability: In view of the algorithm defects of traditional continuum topology optimization which is difficult to converge under complex force-thermal coupling boundary, this invention avoids complex sensitivity derivation and iterative calculation, and adopts a collaborative design method that directly extracts multiphysics features and maps them to implicit level set equations; this method is not only computationally efficient and the model generation is stable, but also enables the fabrication of mirror structures by introducing additive manufacturing technology, which greatly shortens the design and manufacturing cycle. Attached Figure Description

[0044] Figure 1 This is a flowchart illustrating an embodiment of a multi-physics-driven integrated heat-conducting and reflective mirror design method according to the present invention.

[0045] Figure 2 This is a schematic diagram of the initial model of a reflector in an embodiment of a multiphysics-driven reflector-supporting heat-conducting integrated co-design method of the present invention;

[0046] Figure 3 This is a schematic diagram illustrating the Boolean operation conformal matching and fusion of variable-density internal cells and external solid regions in an embodiment of a multi-physics-driven reflector-supporting thermally conductive integrated collaborative design method of the present invention.

[0047] Figure 4This is a schematic diagram of the integrated thermally conductive reflector structure model in an embodiment of the multiphysics-driven reflector-supporting integrated heat-conducting co-design method of the present invention;

[0048] Figure 5 This is a cross-sectional view of the integrated thermally conductive reflector structure model in an embodiment of the multi-physics-driven reflector-supporting integrated heat-conducting co-design method of the present invention;

[0049] Figure 6 The temperature field cloud map is obtained by performing finite element mechanical-thermal coupling simulation analysis on the structural model of the integrated thermally conductive and load-bearing reflector with the same fixed constraints and force-thermal loads as the mechanical and thermal driving fields in an embodiment of the multi-physics field driven reflector design method of the present invention.

[0050] (a) Temperature field cloud map of the front side of the reflector; (b) Temperature field cloud map of the back side of the reflector;

[0051] Figure 7 This is a cloud map of nodal displacement data extracted in an embodiment of the multi-physics-driven integrated heat-conducting co-design method for reflector bearings according to the present invention.

[0052] (a) is a cloud map of the displacement data of the mirror node; (b) is a cloud map of the displacement data of the back node.

[0053] Figure 8 This is a surface shape cloud diagram obtained from the mechanical-thermal coupling simulation analysis of a mirror obtained in an embodiment of the multi-physics-driven integrated heat-conducting co-design method for mirror bearing of the present invention.

[0054] The attached figures are labeled as follows:

[0055] Among them, 1-mirror panel; 2-central light-transmitting hole; 3-back support hole; 4-outer ring; 5-internal design area; 6-external solid area. Detailed Implementation

[0056] To make the objectives, advantages, and features of the present invention clearer, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments. Those skilled in the art should understand that these embodiments are merely used to explain the technical principles of the present invention and are not intended to limit the scope of protection of the present invention.

[0057] like Figure 1 As shown, this embodiment provides a multi-physics-driven integrated heat-conducting and reflective mirror design method, which includes the following steps:

[0058] Step 1: Using the optical design results as input, determine the basic structural parameters of the mirror, such as the mirror aperture, mirror curvature, and thickness. Combined with the operating conditions, select the mirror material, back structure, and support scheme. Construct an initial model of the mirror using Solidworks 3D modeling software, such as... Figure 2 As shown, in this embodiment, the reflector adopts a three-point back support method. The initial model of the reflector includes a mirror panel 1, a central light-transmitting hole 2, three back support holes 3, an outer ring 4, and an internal design domain 5; wherein the mirror panel 1, the central light-transmitting hole 2, the three back support holes 3, and the outer ring 4 are external solid areas 6.

[0059] Step 2: The mathematical essence of maximizing the structural stiffness of the reflector is minimizing global flexibility. According to the energy principle of structural optimization, strain energy density reflects the sensitivity of the material to the total energy absorption of the structure. A fixed constraint with all degrees of freedom is applied to the inner surface of the back support hole of the initial reflector model, and a mechanical load of one times the standard gravitational acceleration is applied vertically downwards along the optical axis to the initial reflector model.

[0060] The static finite element method of the initial model of the reflector under applied mechanical load is solved, and the strain energy density values ​​of all spatial nodes in the internal design domain are extracted to generate the strain energy density field in the three-dimensional coordinate system. , as a driving force in mechanics;

[0061] The mechanical driving field is defined as:

[0062] ;

[0063] in, It is a mechanically driven field; (x,y,z) represents the strain energy density field; () indicates the coordinate positions of the X-axis, Y-axis, and Z-axis in a three-dimensional coordinate system.

[0064] Step 3: The ultimate goal of thermal optimization design is to minimize the thermal deformation of the mirror surface, which is equivalent to minimizing the temperature gradient and thermal compliance. Thermal loads and thermal boundary conditions are applied to the mirror surface and corresponding boundaries of the initial mirror model, specifically:

[0065] A uniform heat source is applied to the mirror surface of the initial model of the reflector to simulate external thermal load;

[0066] Set the air convection coefficient at the circumferential boundary of the initial model of the reflector to be the same as that inside the UAV pod where the reflector is located.

[0067] The ambient temperature is set within the support hole on the back of the initial model of the reflector.

[0068] The initial model of the reflector is solved using thermodynamic finite element method based on thermal load and thermal boundary conditions. The heat flux density values ​​of each spatial node in the design domain are extracted to generate a heat flux density field in a three-dimensional coordinate system. In steady-state heat conduction problems, the path with high heat flux density represents the path with the lowest thermal resistance. Increasing the material at this point facilitates rapid heat dissipation. The thermal driving field is defined as:

[0069]

[0070] in, It is a thermally driven field.

[0071] Step 4: Because the physical dimensions and numerical magnitudes of the mechanical and thermal driving fields are vastly different, direct arithmetic fusion would completely mask the smaller field by the larger one, leading to data distortion. In this embodiment, linear normalization is performed on the mechanical and thermal driving fields, mapping both numerical values ​​to the interval [0,1]. The normalization formula is:

[0072] , ;

[0073] In the formula, This is the normalized strain energy density field. The normalized heat flux density field, This represents the maximum value of the strain energy density field; This represents the minimum value of the strain energy density field; This represents the maximum value of the heat flux density field; q represents the minimum value of the heat flux density field, SED represents the strain energy density, and q represents the heat flux density.

[0074] By introducing structural stiffness and thermal conductivity weighting coefficients, normalized data are weighted and fused to construct a multi-physics composite driving field; the expression is:

[0075] ;

[0076] ;

[0077] In the formula, It is a multi-physics composite driving field. This is the structural stiffness weighting coefficient. This is the thermal conductivity weighting coefficient.

[0078] In this embodiment, the weighting mechanism ensures that the material distribution simultaneously aligns with both the main stress transport path and the main heat diffusion path. (Initial setup) , This is to achieve a balance between structural stiffness and thermal conductivity.

[0079] Step 5: Based on the fact that TPMS Gyroid type unit cells have good specific stiffness and extremely high specific surface area, which have great advantages in mechanical and thermal coupling performance design, TPMS Gyroid type unit cells are selected as the internal unit cells of the initial model of the reflector, and a mapping function between the multi-physics composite driving field and the implicit function level set constant of TPMS Gyroid type unit cells is established.

[0080] The implicit function level set constant of the TPMS Gyroid type unit cell is expressed as:

[0081]

[0082] in, For implicit functions of Gyroid-type unit cells; These represent the periodic dimensions (i.e., cell size) of the TPMS Gyroid type unit cell along the X-axis, Y-axis, and Z-axis in a three-dimensional coordinate system, respectively. This is the implicit function level set constant of the TPMS Gyroid cell. Adjusting this value can change the surface offset of the TPMS Gyroid cell, thereby controlling the relative density of the cell.

[0083] The mapping function expression between the multi-physics composite driving field and the implicit function level set constant of the TPMS Gyroid type unit cell is as follows:

[0084] ;

[0085] f map It is a linear mapping function. express The implicit function level set constant of the TPMS Gyroid-type unit cell. In the multi-physics composite driving field value The higher regions allow for the implicit function level set constant of the TPMS Gyroid type unit cell. Increase, thereby increasing the cell wall thickness (relative density) of TPMS Gyroid-type units; in the multi-physics composite driving field value In areas with lower density, the wall thickness (relative density) is reduced to achieve weight reduction. To prevent structural collapse during later additive manufacturing processes due to excessively low density in the edge regions, a threshold of 0.2 is set to correspond to the minimum wall thickness allowed by the manufacturing process. A threshold of 0.2 corresponds to a TPMSGyroid cell wall thickness of 1 mm. Based on this, in this embodiment, the following settings are implemented: when the multiphysics composite driving field value is greater than 0.2, the relative density of the TPMSGyroid cell is linearly mapped to the multiphysics composite driving field value; when it is less than or equal to 0.2, the multiphysics composite driving field value is assigned a value of 0.2, resulting in a variable-density internal cell.

[0086] Step 6, as follows Figure 3 As shown, Boolean operations are performed to conformally match and fuse the variable-density internal unit cell with the mirror panel 1, the central light-transmitting hole 2, the three back support holes 3, and the outer ring 4 to obtain a structural model of the integrated thermally conductive reflector. Figure 4 and Figure 5 As shown, the same fixed constraints and mechanical loads, thermal loads and thermal boundary conditions as the mechanical driving field and thermal driving field are set, and finite element force-thermal coupling simulation analysis is performed. The displacement data of mirror nodes is extracted, and the rigid body displacement data (translation, off-axis and tilt) is removed. The surface accuracy is calculated by fitting a Zernike polynomial and it is judged whether the surface accuracy meets the preset requirements. If it does, step 7 is executed. Otherwise, the structural stiffness weight coefficient and heat conduction weight coefficient are modified and the process returns to step 4.

[0087] Step 7: The moving cube algorithm is used to transform the structure model of the integrated thermally conductive reflector into a three-dimensional surface mesh. Local mesh refinement and smoothing are performed at the junction of the variable-density internal cell and the external solid region to eliminate geometric sharp corners and ensure the topological continuity of the global model. A processing model suitable for additive manufacturing is generated, and a standard three-dimensional additive manufacturing format file is extracted and output to complete the collaborative design of the integrated thermally conductive reflector driven by multiphysics. The integrated thermally conductive reflector driven by multiphysics can be generated based on the standard three-dimensional additive manufacturing format file.

[0088] The standard 3D additive manufacturing format file is one of the following: STL format, 3MF format, or AMF format.

[0089] The basic structural parameters of the reflector used to construct the initial model of the reflector in this embodiment are shown in Table 1:

[0090] Table 1

[0091]

[0092] Preset requirements: Under the force and heat conditions of 1g gravity and mirror heat load, the design index of the surface shape accuracy of the reflector is: PV≤1 / 4λ, RMS≤1 / 15λ (λ=632.8nm), where PV represents the peak and valley values ​​of the reflector surface, RMS represents the root mean square error of the surface shape of the reflector, and λ represents the wavelength of the incident light.

[0093] Figure 6 The temperature field cloud map is obtained by performing finite element mechanical-thermal coupling simulation analysis on the structural model of the integrated thermal reflector bearing the same fixed constraints and force-thermal loads as the mechanical driving field and thermal driving field in this embodiment.

[0094] Figure 7 The displacement cloud diagram is obtained from the force-thermal coupling simulation analysis of the integrated load-bearing and heat-conducting reflector in this embodiment.

[0095] Figure 8 The image shown is a surface shape cloud diagram from the mechanical-thermal coupling simulation analysis of the integrated thermally conductive reflector obtained in this embodiment.

[0096] Finite element method (FEM) mechanical-thermal coupling simulation analysis and surface shape accuracy calculation were performed on the integrated thermally conductive reflector. Figures 6-8 The results show that the multi-physics-driven integrated heat-conducting co-design method for reflector bearing, as described in this embodiment, yields a reflector surface accuracy of PV=123.13nm<1 / 4λ and RMS=32.53nm<1 / 15λ (λ=632.8nm), which meets the design requirements and verifies the effectiveness and feasibility of the method in this embodiment.

[0097] The TPMS Gyroid type unit cell selected in this embodiment naturally possesses self-supporting process characteristics. Without adding auxiliary support structures to the closed cavity inside the mirror, a three-dimensional processing model suitable for selective laser melting (SLM) additive manufacturing process can be directly generated.

[0098] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit them. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the present invention.

Claims

1. A multi-physics-driven integrated design method for heat conduction and support of a reflector, characterized in that, Includes the following steps: Step 1: Using the optical design results as input, determine the basic structural parameters of the reflector, and construct an initial model of the reflector in conjunction with the operating conditions. The initial model of the reflector includes an internal design domain and an external solid region. Step 2: Apply fixed constraints and mechanical loads to the initial model of the reflector and perform static finite element analysis to extract the strain energy density values ​​of each spatial node in the internal design domain, and generate the strain energy density field in the three-dimensional coordinate system as the mechanical driving field. Step 3: Apply thermal loads and thermal boundary conditions to the mirror surface and corresponding boundaries of the initial model of the reflector, perform thermodynamic finite element analysis, extract the heat flux density values ​​of each spatial node in the internal design domain, and generate a heat flux density field in a three-dimensional coordinate system as a thermal driving field. Step 4: Perform linear normalization on the mechanical and thermal driving fields, and introduce structural stiffness weight coefficients and thermal conduction weight coefficients for weighted fusion to construct a multi-physics composite driving field; Step 5: Select the TPMS Gyroid type unit cell as the internal unit cell of the initial model of the mirror, and establish a mapping function between the multiphysics composite driving field and the implicit function level set constant of the TPMS Gyroid type unit cell; obtain the multiphysics composite driving field value according to the mapping function, and obtain the variable density internal unit cell; when the multiphysics composite driving field value is greater than 0.2, the relative density of the TPMS Gyroid type unit cell is linearly mapped to the multiphysics composite driving field value; when it is less than or equal to 0.2, the multiphysics composite driving field value is assigned to 0.2; Step 6: Perform Boolean operations to conformally match and fuse the variable density internal unit cell with the external solid region to obtain the integrated thermal reflector structure model. Set the same fixed constraints and mechanical loads, thermal loads and thermal boundary conditions as the mechanical driving field and thermal driving field, perform finite element force-thermal coupling simulation analysis, extract mirror node displacement data, remove rigid body displacement data, and calculate the surface accuracy by fitting a polynomial. Determine whether the surface accuracy meets the preset requirements. If yes, proceed to step 7; otherwise, modify the structural stiffness weight coefficient and heat conduction weight coefficient, and return to step 4. Step 7: Use the moving cube algorithm to convert the integrated heat-conducting reflector structure model into a three-dimensional surface mesh, and perform local mesh refinement and smoothing at the junction of the variable density internal cell and the external solid region to generate a processing model suitable for additive manufacturing process, and extract and output a standard three-dimensional additive manufacturing format file.

2. The multi-physics-driven integrated thermal design method for reflector support as described in claim 1, characterized in that: In step 1, the external solid area includes a mirror panel, a central light-transmitting hole, a back support hole, and an outer ring.

3. The multi-physics-driven integrated thermal design method for reflector support as described in claim 2, characterized in that, Step 2 is as follows: A fixed constraint with full degrees of freedom is applied to the inner surface of the back support hole of the initial model of the reflector, and a mechanical load of one standard gravitational acceleration is applied to the initial model of the reflector along the optical axis. A static finite element method is performed on the initial model of the reflector under applied mechanical load to extract the strain energy density values ​​of all spatial nodes in the internal design domain, generating a strain energy density field in a three-dimensional coordinate system. , as a driving force in mechanics; The mechanical driving field is defined as: ； in, For mechanical driving field; () indicates the coordinate positions of the X-axis, Y-axis, and Z-axis in a three-dimensional coordinate system.

4. The multi-physics-driven integrated thermal conductivity and reflector design method according to claim 1, characterized in that, In step 3, the application of thermal loads and thermal boundary conditions to the mirror surface and corresponding boundaries of the initial model of the reflector is as follows: A uniform heat source is applied to the mirror surface of the initial model of the reflector to simulate external thermal load; Set the same air convection coefficient as the external environment of the mirror at the circumferential boundary of the initial model of the mirror; The ambient temperature is set within the support hole on the back of the initial model of the reflector.

5. The multi-physics-driven integrated thermal design method for a reflector bearing and conducting energy according to claim 1, characterized in that, In step 4, the expression for the multi-physics composite driving field is: ； ； in, , ; In the formula, It is a multi-physics composite driving field. This is the structural stiffness weighting coefficient. This is the heat conduction weighting coefficient. This is the normalized strain energy density field. The normalized heat flux density field, This represents the maximum value of the strain energy density field. This represents the minimum value of the strain energy density field. This represents the maximum value of the heat flux density field. q represents the minimum value of the heat flux density field, SED represents the strain energy density, and q represents the heat flux density.

6. The multi-physics-driven integrated thermal conductivity co-design method for a reflector bearing system according to claim 1, characterized in that, In step 5, the implicit function level set constant of the TPMS Gyroid type unit cell is expressed as: ； in, For implicit functions of Gyroid-type unit cells; These represent the periodic dimensions of the TPMS Gyroid type unit cell along the X-axis, Y-axis, and Z-axis in a three-dimensional coordinate system, respectively. The implicit function level set constant of the TPMS Gyroid type unit cell; () indicates the coordinate positions of the X-axis, Y-axis, and Z-axis in a three-dimensional coordinate system.

7. The multi-physics-driven integrated thermal conductivity and reflector design method according to claim 5, characterized in that, In step 5, the mapping function expression between the multi-physics composite driving field and the implicit function level set constant of the TPMS Gyroid type unit cell is: ； f map For mapping functions, ( () represents the coordinate positions of the X, Y, and Z axes in a three-dimensional coordinate system. express The implicit function level set constant of the TPMS Gyroid type unit cell at that location.

8. The multiphysics-driven integrated thermal design method for reflector support as described in claim 7, characterized in that: In step 5, the mapping function is a linear mapping function.

9. The multi-physics-driven integrated thermal design method for reflector support as described in claim 1, characterized in that: In step 7, the standard 3D additive manufacturing format file is one of STL format, 3MF format, or AMF format.

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