A simulation method for super-high-speed kinetic energy impact on solar cell array panel

Abstract

This invention discloses a simulation method for ultra-high-speed kinetic energy impact on solar panels, belonging to the field of spacecraft structure simulation technology. The method includes: establishing a microscopic geometric model comprising a cover glass layer, a germanium layer, front and rear CFRP panels, and an aluminum honeycomb core layer, wherein the CFRP is constructed using fiber and resin micro-units; assigning material models to each component, with the germanium layer adopting an elasto-plastic fluid constitutive model; configuring an FE-SPH adaptive coupling algorithm to automatically transform failed elements into SPH particles; setting multi-material contact algorithms and boundary conditions; and running the simulation to obtain stress wave propagation, debris cloud evolution, and damage characteristics. This invention, by preserving the battery layer and the microscopic CFRP structure and combining it with an adaptive algorithm, achieves high-precision and high-stability simulation of the entire ultra-high-speed impact process, providing a basis for spacecraft protection design.

Description

Technical Field

[0001] This invention belongs to the field of spacecraft structure simulation technology, specifically relating to a simulation method for ultra-high-speed kinetic energy impacting a solar panel. Background Technology

[0002] During their operation in orbit, spacecraft's solar panel arrays are constantly exposed to the space environment, making them vulnerable to high-speed impacts from micrometeoroids and space debris. These impacts often occur at ultra-high speeds of 2-15 km / s, and even millimeter-sized particles can cause perforation of the solar panels, structural damage, and a decrease in power generation performance, seriously threatening the spacecraft's on-orbit safety and lifespan.

[0003] Currently, research methods for this problem mainly fall into three categories: experimental, theoretical, and numerical simulation. Experimental methods, such as two-stage light gas gun impact tests, can directly observe the damage morphology, but they suffer from high experimental costs, limited velocity range, and difficulty in controlling experimental conditions. They cannot systematically cover the velocity distribution range of space debris, nor can they simulate the dynamic damage process of complex multilayer composite structures like solar panels. Theoretical methods mostly rely on empirical formulas to predict the final damage morphology (such as perforation diameter and debris cloud distribution), failing to reveal the entire process of stress wave loading, propagation, and unloading in multilayer materials, and even less able to reflect the physical mechanisms of debris cloud formation and evolution during impact.

[0004] In numerical simulation, traditional finite element method (FEM) is prone to energy non-conservation and element distortion failure under high strain rate and severe distortion conditions, leading to distorted simulation results. While smoothed particle hydrodynamics (SPH) can simulate large deformations and failures, it suffers from tensile instability and low computational efficiency, and is difficult to couple with multilayer composite materials. Existing numerical models are mostly based on simplified or homogenized methods, often omitting or equivalently representing battery layers, making it difficult to observe failure modes such as intralayer and interlayer crack propagation and interlayer debonding. In particular, the lack of a high-fidelity simulation model describing the mechanical damage of the battery solar panel structure limits the rapid assessment of the impact conditions on the battery's mechanical response. Summary of the Invention

[0005] This invention addresses the shortcomings of existing ultra-high-speed impact simulation methods when simulating solar cell array panels in spacecraft, and provides a simulation method that can accurately simulate the full dynamic damage process of solar panels under ultra-high-speed impact while ensuring computational stability and efficiency.

[0006] To solve the above-mentioned technical problems, the present invention is implemented as follows: This invention provides a simulation method for ultra-high-speed kinetic energy impacting a solar cell array panel, comprising the following steps: Step S1: Establish a microscopic geometric model of the solar cell array panel: Based on the actual dimensions of the Sentinel-1A solar panel composite structure, construct a geometric model including a cover glass layer, a germanium layer, a front CFRP panel, an aluminum honeycomb core layer, and a rear CFRP panel; wherein, the germanium layer is a simplified single-layer structure representing the solar cell layer; the aluminum honeycomb core layer is constructed using an explicit modeling method; the front CFRP panel and the rear CFRP panel are both constructed by repeatedly mirroring and arraying to replicate the tiny sub-units of fibers and resin to build the microscopic structure; Step S2: Mesh the geometric model established in Step S1 and assign corresponding material models to each structural part; wherein, the cover glass layer adopts the Johnson-Holmquist-Ceramics brittle material model, the germanium layer adopts the elastoplastic fluid constitutive model combined with the Grüneisen equation of state, the fibers in the CFRP panel adopt the MAT_059 orthotropic material model, the resin adopts the elastoplastic fluid constitutive model, and the aluminum honeycomb core layer and impact projectile adopt the Johnson-Cook strength model and the Grüneisen equation of state; Step S3: In the explicit dynamic analysis software, configure the finite element-smooth particle fluid dynamics adaptive coupling algorithm for the model, so that when the equivalent plastic strain of any material element in the model reaches its material failure threshold, the element is automatically converted into an SPH particle and inherits the mass, position and velocity information of the original element. Step S4: Set contact algorithm and boundary conditions: Define erosion contact for the contact interface between different components, and apply non-reflective boundary conditions to the edges of the aluminum honeycomb layer and CFRP layer; Step S5: Set simulation stability control parameters, including contact stiffness scaling factor, time step scaling factor, and hourglass control parameters; Step S6: Run simulation calculations to obtain and analyze the stress wave propagation process, debris cloud evolution morphology, perforation size of the front and rear panels, and mechanical damage characteristics of each structural layer of the solar cell array panel under ultra-high speed impact.

[0007] Furthermore, in step S1, the modeling thickness of the cover glass layer is 0.10 mm, the modeling thickness of the germanium layer is 0.10 mm, the modeling thickness of the front and rear CFRP panels is 0.75 mm, the modeling height of the aluminum honeycomb core layer is 18.40 mm, the honeycomb foil wall thickness is 0.0254 mm, and the honeycomb lattice size is 4.7625 mm.

[0008] Furthermore, in step S1, the planar dimensions of the cover glass layer and the germanium layer are 30.00mm × 40.00mm, and the planar dimensions of the CFRP / aluminum honeycomb / CFRP sandwich structure are 40.00mm × 80.00mm.

[0009] Furthermore, in step S2, the material parameters of the germanium layer include: a density of 5328 kg / m³, a shear modulus of 45 GPa, a yield stress of 120 MPa, a Grüneisen equation of state constant CC of 1750 m / s, S1S1 of 1.75, S2S2 and S3S3 of 0, and γ0γ0 of 0.5; the failure criterion is that the maximum principal stress reaches 93 MPa or the equivalent strain reaches 0.035.

[0010] Furthermore, in step S2, the failure criterion for the cover glass layer is that the maximum principal stress reaches 170 MPa or the maximum strain reaches 0.3; when the impact projectile is a nylon projectile, its failure criterion is that the maximum principal stress reaches 80 MPa or the principal strain reaches 0.65.

[0011] Furthermore, in step S3, the finite element-smooth particle hydrodynamic adaptive coupling algorithm is implemented using keywords in the LS-DYNA software. Implement DEFINE_ADAPTIVE_SOLID_TO_SPH and set ICPL=1 and IOPT=1.

[0012] Further, in step S4, the erosion contact includes: erosion surface contact defined with the keyword CONTACT_ERODING_SURFACE_TO_SURFACE for the contact interface between different components; erosion single-sided contact defined with the keyword CONTACT_ERODING_SINGLE_SURFACE for the intralayer contact of each CFRP panel itself; and erosion single-sided contact defined with the keyword CONTACT_ERODING_SINGLE_SURFACE for the unit contact within the part. The internal contact of CONTACT_INTERIOR.

[0013] Furthermore, step S4 also includes using keywords. CONTACT_TIEBREAK_NODES_TO_SURFACE binds the nodes and surfaces between the cover glass layer and the front CFRP panel to simulate an adhesive bond.

[0014] Furthermore, the impact projectile is a nylon projectile or an aluminum projectile, and its impact velocity is set to 2 km / s to 15 km / s.

[0015] Furthermore, step S7 is included: based on the damage information obtained in step S6, the influence of different material parameters or impact conditions on the damage morphology and debris cloud diffusion of the solar cell array panel is analyzed to optimize its protective structure design.

[0016] Compared with the prior art, the present invention has the following beneficial effects: 1) More reasonable model: By employing a mesoscopic modeling method, the functionally crucial battery layer (germanium layer) and the mechanically complex CFRP layer are preserved. This allows for accurate simulation of crack propagation, interlayer debonding, and mechanical coupling failure of adjacent layers in the critical battery layer, revealing phenomena that are difficult to observe experimentally. Compared to homogenized and semi-homogenized models, the mesoscopic model of this invention is more conducive to accurately simulating damage evolution.

[0017] 2) More stable simulation: The finite element-SPH adaptive coupling method is introduced, which automatically transforms the element into a particle when the element fails, solving the problems of element distortion and energy non-conservation in FEM, while overcoming the tensile instability of pure SPH.

[0018] 3) Material model innovation: To address the lack of material parameters for germanium layers (battery layers) under ultra-high-speed impact, a high-fidelity simulation of the battery layer was achieved by surveying limited data and using an elastoplastic fluid constitutive model and the Grüneisen equation of state.

[0019] 4) Deeper understanding of the mechanism: This invention can not only obtain results such as perforation size, debris cloud quantity, and internal impact evolution process, but also fully reproduce the entire process of stress wave propagation, debris cloud evolution, front and rear plate perforation and secondary damage of honeycomb, providing detailed theoretical basis for protective design.

[0020] 5) High engineering guidance value: The output quantitative damage indicators (perforation size, fragment velocity distribution, energy dissipation law, fragment mass distribution) can be directly used for the protection optimization design of solar panels and other spacecraft components, and have important engineering application value. Attached Figure Description

[0021] To more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort, wherein: Figure 1 This is a schematic diagram of a mesoscopic model of the Sentinel-1A solar panel composite structure provided by the present invention, wherein (a) is a physical image, (b) is a dimensional diagram, (c) is a numerical model, and (d) is the modeling process of the mesoscopic CFRP. Figure 2 The experimental and simulated damage morphology comparison diagrams provided by the present invention are shown in which (a) is the front panel, (b) is the rear panel, and (c) is the honeycomb. Figure 3The diagram shows the dynamic evolution of the solar panel composite structure provided by the present invention, wherein (a) is a cross-sectional view, (b) is a top-view perspective view, (c) is a bottom-view perspective view, and (d) is a honeycomb diagram. Figure 4 The diagrams provided by this invention are for verifying the statistical results of the fragments. In the diagram, (a) shows the relationship between the characteristic size and the cumulative number of the total fragments, and (b)-(e) show the distribution relationship between the characteristic size and the cumulative number of glass, germanium, CFRP and cellular fragments, respectively. Detailed Implementation

[0022] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0023] The terms "first," "second," etc., used in the specification and claims of this invention are used to distinguish similar objects and not to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that embodiments of the invention can be implemented in orders other than those illustrated or described herein, and the objects distinguished by "first," "second," etc., are generally of the same class and the number of objects is not limited; for example, a first object can be one or more. Furthermore, in the specification and claims, "and / or" indicates at least one of the connected objects, and the character " / " generally indicates that the preceding and following objects are in an "or" relationship.

[0024] 1. Geometric modeling like Figure 1 As shown, the Sentinel-1A solar panel composite structure is a typical sandwich structure, consisting of a front panel and a rear panel sandwiching an aluminum honeycomb support layer. The front panel is composed of CFRP, with sequentially laid cell layers and a cover glass, with thicknesses of 0.75mm, 0.40mm, and 0.10mm, respectively. The rear panel is typically composed of CFRP of the same thickness as the front panel (0.75mm). The support structure uses a hexagonal aluminum honeycomb layer with a height of 18.40mm, a honeycomb foil wall thickness of 0.0254mm (0.001 inches), and a honeycomb cell size of 4.7625mm (3 / 16 inches).

[0025] Based on the actual dimensions of the Sentinel-1A solar panel composite structure, this invention establishes a 1 / 2 numerical model of it, as follows: Figure 1(c) shows the detailed model, which includes a CFRP / aluminum honeycomb / CFRP sandwich structure with dimensions of 40.00mm × 80.00mm, and a cover glass and battery layer with dimensions of 30.00mm × 40.00mm.

[0026] The Sentinel-1A solar panel uses triple-junction gallium arsenide solar cells, which are multi-layered structures consisting of a top cell, a middle cell, a bottom cell, and a germanium substrate. Because the germanium substrate is much thicker than the other cell layers (approximately 50 times thicker) and the mechanical properties of the different layers are similar, this invention retains only the germanium substrate to improve computational efficiency and approximates it to 0.10 mm. The cover glass and germanium cell layers are modeled using homogeneous solid cells.

[0027] To characterize the microchannel effect of the aluminum honeycomb core layer, an explicit modeling method was employed. To reflect the anisotropy of CFRP, this invention constructs a micro-scale CFRP by repeatedly mirroring and arraying the micro-subunits of fibers and resin, such as... Figure 1 As shown in (d). In the figure, red represents the projectile, green represents the cover glass, yellow represents the fiber, cyan represents germanium, pink represents epoxy resin, and blue represents aluminum honeycomb.

[0028] 2. FE-SPH Adaptive Coupling Algorithm Settings The numerical calculations of this invention employ the FE-SPH adaptive method in LS-DYNA, which is well-suited for addressing energy non-conservation and tensile instability issues in ultra-high-speed impact simulations. In the adaptive system, after FEM failure, the particles are converted into SPH particles of the same mass and velocity to continue participating in the calculation. After the calculation is completed, the residual elements correspond to the material that is not yet completely damaged, which can be physically considered as larger fragments in a debris cloud, while the SPH particles correspond to the material that is completely damaged.

[0029] By keywords DEFINE_ADAPTIVE_SOLID_TO_SPH implements the coupling conversion between cells and particles. The key parameters are set as follows: ICPL=1 (activate the coupling algorithm), IOPT=1 (activate particles after cell failure). When a cell reaches the failure threshold, the cell is deleted and converted into an SPH particle to continue participating in the calculation, inheriting the mass, position, and velocity information of the original cell.

[0030] To realistically simulate impact conditions, this invention applies non-reflective boundary conditions only at the edges of the aluminum honeycomb layer and the CFRP layer to eliminate artificial wave reflections; no boundary conditions are applied to the cover glass and the germanium layer.

[0031] 3. Multi-material contact treatment Considering the diverse material characteristics of solar cell array panels, the following contact definition method is adopted: For the contact interface between the cover glass layer, the front CFRP panel, the aluminum honeycomb core layer, and the rear CFRP panel, the keyword is defined as... The eroded surface of CONTACT_ERODING_SURFACE_TO_SURFACE is in contact with the surface of the erosion surface. For the in-layer contacts of each CFRP panel, the keyword is defined as follows. Erosion of single-sided contact in CONTACT_ERODING_SINGLE_SURFACE; For unit contacts within each part, the keyword is defined as The internal contact of CONTACT_INTERIOR.

[0032] exist In CONTROL_CONTACT, set the stiffness scaling factor SLFSFAC=10 to prevent element penetration. In CONTROL_TIMESTEP, the time step scaling factor DT is set to 0.1 to ensure computational stability. The SPH particle volume parameter ITIK is set to 1.

[0033] Since the layers of a solar cell array panel are mainly connected by adhesives, and the adhesive layer is extremely thin, its impact on the mechanical damage mechanism is negligible. Therefore, keywords are used in the modeling process. CONTACT_TIEBREAK_NODES_TO_SURFACE binds the nodes and surfaces between the cover glass layer and the front CFRP panel to simulate an adhesive bond.

[0034] 4. Material Model and Parameters 4.1 Nylon bullets This invention selects Nylon 6 (PA6), with well-defined material parameters, as an equivalent substitute material. An elastoplastic fluid constitutive model is used to describe the shear and yield behavior of the material, and the Grüneisen equation of state is combined to characterize the volumetric response and internal energy evolution. Material parameters are shown in Table 1. Material failure is determined when the maximum principal stress reaches 80 MPa or the principal strain reaches 0.65.

[0035] Table 1 Material parameters of nylon 4.2 Cover with glass The Johnson-Holmquist-Ceramics (JH-2) brittle material model was adopted, and the material parameters are shown in Table 2. Failure criteria of maximum principal stress (170 MPa) and maximum strain (0.3) were introduced to characterize the mechanical damage of the glass layer during impact.

[0036] Table 2 Material parameters of the cover glass 4.3 CFRP This invention employs a microscopic modeling method to study the mechanical damage and dynamic response of CFRP under ultra-high-speed impact. The fiber is modeled using the MAT_059 orthotropic material model, and the resin is modeled using an elastoplastic fluid constitutive model combined with the Grüneisen equation of state. The material parameters of the fiber and resin are listed in Table 3.

[0037] Table 3 Material parameters of CFRP 4.4 Germanium layer (battery layer) Germanium, as a typical brittle material, is described in this invention using an elastoplastic fluid constitutive model and the Grüneisen equation of state to approximate the mechanical characteristics of the germanium layer. A maximum principal stress threshold of 93 MPa and an equivalent strain threshold of 0.035 are set to describe the tensile fracture behavior. The material parameters of germanium are listed in Table 4.

[0038] Table 4 Material parameters of germanium 4.5 Aluminum honeycomb Aluminum honeycomb layers typically exhibit crushing, shear failure, and local unit collapse mechanical damage behavior under ultra-high-speed impact. This invention uses the Johnson-Cook constitutive model and Grüneisen equation of state to describe the dynamic response of aluminum honeycomb layers, and the parameters are listed in Table 5.

[0039] Table 5 Material parameters of aluminum honeycomb 5. Model Validation To verify the accuracy of the simulation, this invention reproduced the impact experiment of Giacomuzzo et al. using the method described above, such as... Figure 2 , Figure 3 , Figure 4 As shown in Table 6.

[0040] Figure 3 This demonstrates the dynamic evolution of solar panel composite structures from different perspectives. t At 1 μs, the projectile has not yet completely penetrated the front panel, and no obvious main debris cloud and secondary debris cloud have yet formed inside the structure, such as Figure 3 As shown in (a). To t =4μs, the debris cloud gradually begins to propagate within the structure and differentiates into primary and secondary debris clouds, which is caused by the microchannel effect of the honeycomb structure. t =10μs, arriving first from the debris cloud and penetrating the rear panel. t =20μs, the main debris cloud impacts the rear panel at an inclined angle, some debris is deflected and forms a horizontal debris cloud at the bottom of the cell, causing greater mechanical damage to the bottom area of ​​the cell.

[0041] Figure 3 (b) illustrates the damage evolution characteristics of the glass and germanium layers in the front panel. Both materials exhibit typical brittle fracture behavior, with radial crack size gradually increasing over time. Due to the impedance difference between the two materials, the germanium layer exhibits more severe fragmentation damage.

[0042] like Figure 2 As shown, both the experimental and simulation results indicate significant peeling of the front panel, with perforations exhibiting an elliptical shape. Figure 2 As shown in (a), the rear panel forms two approximately symmetrical triangular perforations and exhibits anisotropic characteristics, such as... Figure 2 As shown in (b). Both experimental and simulation results show approximately circular cavity regions inside the honeycomb structure, as... Figure 2 (c) shows the comparison results of the perforation size. Table 6 shows that the perforation size in the main propagation direction is in good agreement with the experimental results, with relative errors of 2.9% and 7.6%, respectively.

[0043] Table 6 Comparison of Experimental and Simulation Results Figure 4 The statistical results of the fragments were demonstrated. The simulation results (2D and 3D statistical methods) and the experimental results are on the same order of magnitude in terms of fragment feature size and cumulative quantity distribution, and there are acceptable geometric deviations between the two statistical methods in the simulation results. Figure 4 (b)-(e) respectively show the characteristic size and cumulative number distribution of glass, germanium, CFRP, and honeycomb fragments. Due to its higher impedance, germanium has more fragments than glass. Due to the anisotropy of CFRP, its fragments are mostly distributed in strips. Large fragments of aluminum honeycomb are mainly formed by ductile tearing mechanisms dominated by inertial motion, and its fragments are mostly blocky.

[0044] In summary, the microscopic simulation method, material model, and material parameters employed in this invention can reasonably characterize the mechanical damage evolution and fragmentation features of different materials under ultra-high-speed impact. Therefore, this numerical model can reliably reflect the structural response and load transfer characteristics.

[0045] 6. Results Analysis By applying the method of this invention, the process of a typical solar cell array panel structure under ultra-high-speed impact was simulated, successfully obtaining dynamic images of the entire process from stress wave loading, front panel perforation, debris cloud expansion, rear panel perforation, to secondary damage to the honeycomb core by splashed debris. In particular, by comparing simulation cases with different cover glass thicknesses and other parameters, the influence of various structural parameters on the peak impact stress, rear panel perforation size, and debris cloud diffusion angle can be quantitatively analyzed, clearly revealing the protective mechanism of the structure.

[0046] It should be noted that, in this document, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or system that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or system. Unless otherwise specified, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or system that includes that element.

[0047] Furthermore, it should be noted that the scope of the methods and systems in the embodiments of the present invention is not limited to performing functions in the order shown or discussed, but may also include performing functions substantially simultaneously or in the reverse order, depending on the functions involved. For example, the described methods may be performed in a different order than described, and various steps may be added, omitted, or combined. In addition, features described with reference to certain examples may be combined in other examples.

[0048] The embodiments of the present invention have been described above with reference to the accompanying drawings. However, the present invention is not limited to the specific embodiments described above. The specific embodiments described above are merely illustrative and not restrictive. Those skilled in the art can make many other modifications under the guidance of the present invention without departing from the spirit and scope of the claims, and all of these modifications are within the protection scope of the present invention.

Claims

1. A simulation method for ultra-high-speed kinetic energy impacting a solar cell array panel, characterized in that, Includes the following steps: Step S1: Establish a microscopic geometric model of the solar cell array panel: Based on the actual dimensions of the Sentinel-1A solar panel composite structure, construct a geometric model including a cover glass layer, a germanium layer, a front CFRP panel, an aluminum honeycomb core layer, and a rear CFRP panel; wherein, the germanium layer is a simplified single-layer structure representing the solar cell layer; the aluminum honeycomb core layer is constructed using an explicit modeling method; the front CFRP panel and the rear CFRP panel are both constructed by repeatedly mirroring and arraying to replicate the tiny sub-units of fibers and resin to build the microscopic structure; Step S2: Mesh the geometric model established in Step S1 and assign corresponding material models to each structural part; wherein, the cover glass layer adopts the Johnson-Holmquist-Ceramics brittle material model, the germanium layer adopts the elastoplastic fluid constitutive model combined with the Grüneisen equation of state, the fibers in the CFRP panel adopt the MAT_059 orthotropic material model, the resin adopts the elastoplastic fluid constitutive model, and the aluminum honeycomb core layer and impact projectile adopt the Johnson-Cook strength model and the Grüneisen equation of state; Step S3: In the explicit dynamic analysis software, configure the finite element-smooth particle fluid dynamics adaptive coupling algorithm for the model, so that when the equivalent plastic strain of any material element in the model reaches its material failure threshold, the element is automatically converted into an SPH particle and inherits the mass, position and velocity information of the original element. Step S4: Set contact algorithm and boundary conditions: Define erosion contact for the contact interface between different components, and apply non-reflective boundary conditions to the edges of the aluminum honeycomb layer and CFRP layer; Step S5: Set simulation stability control parameters, including contact stiffness scaling factor, time step scaling factor, and hourglass control parameters; Step S6: Run simulation calculations to obtain and analyze the stress wave propagation process, debris cloud evolution morphology, perforation size of the front and rear panels, and mechanical damage characteristics of each structural layer of the solar cell array panel under ultra-high speed impact.

2. The simulation method according to claim 1, characterized in that, In step S1, the modeling thickness of the cover glass layer is 0.10 mm, the modeling thickness of the germanium layer is 0.10 mm, the modeling thickness of the front and rear CFRP panels is 0.75 mm, the modeling height of the aluminum honeycomb core layer is 18.40 mm, the honeycomb foil wall thickness is 0.0254 mm, and the honeycomb lattice size is 4.7625 mm.

3. The simulation method according to claim 1, characterized in that, In step S1, the planar dimensions of the cover glass layer and the germanium layer are 30.00mm × 40.00mm, and the planar dimensions of the CFRP / aluminum honeycomb / CFRP sandwich structure are 40.00mm × 80.00mm.

4. The simulation method according to claim 1, characterized in that, In step S2, the material parameters of the germanium layer include: density of 5328 kg / m³, shear modulus of 45 GPa, yield stress of 120 MPa, Grüneisen equation of state constant C0 of 1750 m / s, S1 of 1.75, S2 and S3 of 0, and γ0 of 0.5; the failure criterion is that the maximum principal stress reaches 93 MPa or the equivalent strain reaches 0.

035.

5. The simulation method according to claim 1, characterized in that, In step S2, the failure criterion for the cover glass layer is that the maximum principal stress reaches 170 MPa or the maximum strain reaches 0.3; when the impact projectile is a nylon projectile, the failure criterion is that the maximum principal stress reaches 80 MPa or the principal strain reaches 0.

65.

6. The simulation method according to claim 1, characterized in that, In step S3, the finite element-smooth particle hydrodynamic adaptive coupling algorithm is implemented using the keyword in the LS-DYNA software. Implement DEFINE_ADAPTIVE_SOLID_TO_SPH and set ICPL=1 and IOPT=1.

7. The simulation method according to claim 1, characterized in that, In step S4, the erosion contact includes: erosion surface contact defined with the keyword CONTACT_ERODING_SURFACE_TO_SURFACE for the contact interface between different components; erosion single-sided contact defined with the keyword CONTACT_ERODING_SINGLE_SURFACE for the intralayer contact of each CFRP panel; and erosion single-sided contact defined with the keyword CONTACT_ERODING_SINGLE_SURFACE for the unit contact within the part. The internal contact of CONTACT_INTERIOR.

8. The simulation method according to claim 1, characterized in that, Step S4 also includes using keywords CONTACT_TIEBREAK_NODES_TO_SURFACE binds the nodes and surfaces between the cover glass layer and the front CFRP panel to simulate an adhesive bond.

9. The simulation method according to claim 1, characterized in that, The impact projectile is a nylon projectile or an aluminum projectile, and its impact velocity is set to 2 km / s to 15 km / s.

10. The simulation method according to any one of claims 1 to 9, characterized in that, It also includes step S7: Based on the damage information obtained in step S6, analyze the impact of different material parameters or impact conditions on the damage morphology and debris cloud diffusion of the solar cell array panel, so as to optimize its protective structure design.

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