Dynamic analysis method and system for anti-seismic performance and stress distribution of multi-modal ceramic material

Abstract

The application provides a dynamic analysis method and system for the anti-seismic performance and stress distribution of a multi-modal ceramic material, and relates to the field of dynamic analysis. The method is based on the geometric configuration and loading direction of a test piece, and a multi-layer non-uniform virtual compensation layer grid is generated by extending the test piece real boundary. The layered density is dynamically adjusted according to a seismic frequency spectrum. The test piece is a ceramic material sample. According to the zoning structure of the virtual compensation layer grid, a stress distribution reference data field is constructed. The optimal boundary adjustment force is calculated, and the parameters of the virtual compensation layer grid are dynamically adjusted. After the adjustment is completed, the stress distribution reference data field is updated. The corrected stress data is collected, adaptively weighted and fused with historical stress data, and the stress evolution trend is tracked to ensure high matching degree between the experimental conditions and the real environment, and to ensure more accurate stress evolution analysis of the ceramic material under complex vibration environment, thereby providing more valuable data support for anti-seismic design and engineering application.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of dynamic analysis, and more specifically, to a multi-modal ceramic material anti-seismic performance and stress distribution dynamic analysis method and system. BACKGROUND

[0002] In recent years, ceramic materials have been widely used in aerospace, precision manufacturing, and structural engineering due to their excellent high-temperature resistance, corrosion resistance, and high strength. However, due to the inherent brittleness of ceramic materials, their anti-seismic performance and stress distribution characteristics have been an important research direction in engineering applications. Current research on the anti-seismic performance of ceramic materials mainly focuses on two aspects: one is through material modification, such as adding toughening phases or optimizing particle structures, to improve the fracture toughness of the material; the other is through structural optimization, such as using multi-layer composite design or pre-stress technology, to improve the dynamic response performance of the material.

[0003] The existing technology still has many deficiencies in the analysis of ceramic material anti-seismic performance and stress distribution. On the one hand, traditional experimental methods have limitations in simulating actual boundary conditions. The test specimen is usually fixed with a rigid clamp. Although this method can provide good repeatability, it cannot truly reproduce the boundary constraint effect of ceramic structures under complex working conditions, thereby affecting the reliability of experimental data. On the other hand, current stress analysis methods are mainly based on static or quasi-static loading modes, and do not fully consider the dynamic influence of the vibration spectrum, resulting in experimental results that are difficult to fully reflect the long-term service state of ceramic materials in real vibration environments. SUMMARY

[0004] To solve the above technical problems, the present application is proposed. The present application provides a multi-modal ceramic material anti-seismic performance and stress distribution dynamic analysis method and system.

[0005] According to one aspect of the present application, a multi-modal ceramic material anti-seismic performance and stress distribution dynamic analysis system is provided, comprising:

[0006] A multi-layer boundary compensation device module generates a multi-layer non-uniform virtual compensation layer grid based on the geometric configuration and loading direction of the test specimen outside the real boundary of the test specimen, and the layer density is dynamically adjusted according to the vibration spectrum diagram; the test specimen is a ceramic material sample;

[0007] A stress distribution calculation module constructs a stress distribution reference data field according to the partition structure of the virtual compensation layer grid;

[0008] A reverse boundary correction module calculates the optimal boundary adjustment force and dynamically adjusts the virtual compensation layer grid parameters. After adjustment, the stress distribution reference data field is updated;

[0009] A dynamic data iteration module collects the corrected stress data, adaptively weights and fuses the historical stress data, and tracks the stress evolution trend to ensure high matching degree between the experimental conditions and the real environment.

[0010] Further, the geometric configuration is the shape of the ceramic material test piece; the loading direction is the external force action; the generation of the multi-layer non-uniform virtual compensation layer grid includes: determining the boundary compensation area according to the geometric configuration and the loading direction; calculating the boundary curvature distribution according to the geometric configuration of the test piece to determine the area that needs to be compensated; dividing the grid of the real boundary of the test piece to ensure that the boundary curvature of the initial grid matches the test piece; calculating the normal direction of each grid point and adjusting the grid node distribution by using the Laplace smoothing algorithm; and expanding the compensation layer according to the exponential decreasing method.

[0011] Further, the adjustment of the layered density includes: measuring the vibration response of the test piece at different frequencies and drawing a vibration spectrum graph; dividing the high-frequency sensitive area and the low-frequency area according to the frequency spectrum analysis; the high-frequency sensitive area adopts a fine grid, and the low-frequency area adopts a sparse grid; and the grid size decreases layer by layer in the transition area.

[0012] Further, the construction of the stress distribution reference data field includes: dividing the test piece area into a plurality of stress calculation sub-areas according to the partition structure of the compensation layer grid, each area corresponding to a grid unit; setting the boundary conditions for stress field calculation; using a finite element simulation method to solve the stress field distribution of the ceramic test piece under the given boundary conditions; and mapping the calculated stress distribution data to the compensation layer grid to form a discretized reference data field.

[0013] Further, the stress distribution calculation module includes a boundary adjustment force calculation unit for calculating the optimal boundary adjustment force based on the boundary conditions; a virtual compensation layer grid parameter adjustment unit for dynamically adjusting the stiffness and damping parameters of the virtual compensation layer grid according to the optimal boundary adjustment force; and a stress distribution reference data field updating unit for recalculating and updating the stress distribution reference data field after completing the compensation layer parameter adjustment.

[0014] Further, the optimal boundary adjustment force is an optimal solution obtained by using the conjugate gradient method.

[0015] Further, the dynamic adjustment of the stiffness and damping parameters of the virtual compensation layer grid includes: setting the stiffness and damping parameters of different layers respectively by using a multi-layer compensation grid structure; dynamically calculating the adjustment amount of each layer according to the calculation results of the stress distribution and the optimal boundary adjustment force; applying the adjustment amount and monitoring the change of the stress distribution to confirm whether the adjustment of the stiffness and damping achieves the ideal effect.

[0016] Further, the dynamic calculation of the adjustment amount of each layer comprises: comparing the current stress state of the compensation layer grid with the stress distribution reference data field to determine the stress change trend of different grid layers; calculating the stress change rate of each layer of the compensation grid to ensure that the adjustment direction of the stiffness and damping parameters is consistent with the actual stress demand; the stiffness adjustment requires the adjustment amount to gradually attenuate between different compensation layers, and the size of the adjustment amplitude depends on the relative position of the current compensation layer and the adjustment result of the previous layer, so as to ensure that the stiffness change will not be abrupt; when the damping is adjusted, the damping coefficient is increased according to the action direction of the adjustment force, and the oscillation effect of the high stress gradient area is reduced.

[0017] Further, the tracking of the stress evolution trend combines sliding window filtering and an autoregressive integral moving average model; the sliding window filtering is used to eliminate noise in the data and avoid accidental errors from interfering with the analysis results; and the autoregressive integral moving average model is used to fit the long-term stress evolution trend and predict the future stress distribution state.

[0018] According to another aspect of the present application, a method for dynamic analysis of the anti-seismic performance and stress distribution of a multi-modal ceramic material is provided, which comprises: based on the geometric configuration and loading direction of a test piece, generating a multi-layer non-uniform virtual compensation layer grid outside the real boundary of the test piece, and dynamically adjusting the layer density according to the seismic frequency spectrum; the test piece is a ceramic material sample; constructing a stress distribution reference data field according to the partition structure of the virtual compensation layer grid; calculating an optimal boundary adjustment force and dynamically adjusting the parameters of the virtual compensation layer grid, after the adjustment is completed, updating the stress distribution reference data field; collecting the corrected stress data, adaptively weighting and fusing the historical stress data, and tracking the stress evolution trend to ensure high matching degree between the experimental conditions and the real environment.

[0019] Compared with the prior art, the present application improves the accuracy of the analysis of the anti-seismic performance of the ceramic material by multi-layer boundary compensation and dynamic adjustment of the grid density, reduces the influence of the boundary effect on the stress distribution calculation, optimizes the virtual compensation layer parameters by reverse boundary correction, makes the experimental environment closer to the real stress state, improves the reliability of the stress calculation, realizes the fusion of the historical data and the real-time stress data through dynamic data iteration, and improves the stability of the stress distribution prediction. Finally, the present application ensures that the stress evolution analysis of the ceramic material in a complex vibration environment is more accurate, and provides more reference value data support for anti-seismic design and engineering application. BRIEF DESCRIPTION OF DRAWINGS

[0020] In order to more clearly illustrate the technical solutions of the embodiments of the present application or the prior art, the following will briefly introduce the drawings needed to be used in the embodiments or prior art description. Obviously, the drawings described below are only some embodiments of the present application, and the other drawings can be obtained by those skilled in the art without any creative effort based on these drawings. In the drawings:

[0021] Figure 1 The system block diagram of the multi-modal ceramic material anti-seismic performance and stress distribution dynamic analysis system according to the embodiment of the present application.

[0022] Figure 2 The block diagram of the reverse boundary correction module in the multi-modal ceramic material anti-seismic performance and stress distribution dynamic analysis system according to the embodiment of the present application.

[0023] Figure 3 The block diagram of the dynamic data iteration module in the multi-modal ceramic material anti-seismic performance and stress distribution dynamic analysis system according to the embodiment of the present application.

[0024] Figure 4 The flow chart of the multi-modal ceramic material anti-seismic performance and stress distribution dynamic analysis method according to the embodiment of the present application. DETAILED DESCRIPTION

[0025] In the following, the example embodiments according to the present application will be described in detail with reference to the drawings. Obviously, the described embodiments are only some of the embodiments of the present application, rather than all the embodiments of the present application, and it should be understood that the present application is not limited to the example embodiments described herein.

[0026] As described in the above background, the prior art still has many deficiencies in the analysis of ceramic material anti-seismic performance and stress distribution. On the one hand, the traditional test method has limitations in simulating the actual boundary conditions. The test piece is usually fixed by a rigid clamp. Although this method can provide good repeatability, it cannot truly reproduce the boundary constraint effect of the ceramic structure under complex working conditions, thereby affecting the reliability of the experimental data. On the other hand, the current stress analysis method is mainly based on static or quasi-static loading mode, and does not fully consider the dynamic influence of the vibration spectrum, resulting in that the experimental results are difficult to fully reflect the long-term service state of the ceramic material in the real vibration environment. The present application proposes a multi-modal ceramic material anti-seismic performance and stress distribution dynamic analysis system, which comprises:

[0027] Figure 1 The system block diagram of the multi-modal ceramic material anti-seismic performance and stress distribution dynamic analysis system according to the embodiment of the present application. As shown in Figure 1 In the multi-modal ceramic material anti-seismic performance and stress distribution dynamic analysis system, it comprises:

[0028] The multi-layer boundary compensation device module 100 generates a multi-layer non-uniform virtual compensation layer grid outside the real boundary of the test piece based on the geometric configuration and loading direction of the test piece, and the layer density is dynamically adjusted according to the seismic frequency spectrum; the stress distribution calculation module 200 constructs a stress distribution reference data field according to the partition structure of the virtual compensation layer grid; the reverse boundary correction module 300 calculates the optimal boundary adjustment force and dynamically adjusts the parameters of the virtual compensation layer grid, and after the adjustment is completed, the stress distribution reference data field is updated; the dynamic data iteration module 400 collects the corrected stress data, adaptively weights and fuses with the historical stress data, and tracks the stress evolution trend, ensuring high matching degree of experimental conditions and real environment.

[0029] In the embodiments of the present application, the multi-layer boundary compensation device module 100 specifically includes: generating a multi-layer non-uniform virtual compensation layer grid outside the real boundary of the test piece based on the geometric configuration and loading direction of the test piece.

[0030] It should be noted that the test piece is a ceramic material sample, and the shape of the ceramic material sample needs to be standardized to ensure comparability in experimental and simulation calculations, and the size of the test piece needs to consider the loading capacity of the test equipment to avoid data measurement errors caused by too small size or excessive boundary effects caused by too large size. In addition, the surface of the test piece needs to be processed with high precision, such as polishing or laser processing, to reduce the influence of surface defects on stress distribution. Importantly, the boundary of the test piece must have clear geometric characteristics, such as smooth straight edges or regular curved edges, so that the compensation device can extend the grid outside the test piece boundary. For boundaries that may cause stress concentration effects (such as notches or sharp corners), additional consideration of fine processing of the compensation layer grid is required.

[0031] Before constructing the multi-layer boundary compensation device, the geometric configuration of the test piece and the loading direction need to be determined first. This is because the stress distribution of ceramic materials under vibration or impact load will be affected by shape, boundary constraints, and loading method. Geometric configuration refers to the shape of the ceramic material test piece (such as rectangle, circle, irregular shape, etc.), and different shapes will have different stress concentration situations at the boundary when subjected to external force. For example, the corners of a rectangular test piece often have stress concentration, while a circular test piece has more uniform stress distribution at the edge. In addition, the loading direction determines the way stress is transmitted, for example, vertical loading mainly causes compression deformation, while horizontal loading may cause shear stress. Therefore, when constructing the boundary compensation structure, the boundary compensation area needs to be determined according to the geometric configuration and loading direction, that is, to identify which parts are prone to calculation errors during vibration testing and to construct virtual compensation layers in these parts.

[0032] Generally, uniform meshing is adopted for finite element analysis, but this method can cause insufficient calculation accuracy, and stress errors can occur at the boundary. To solve this problem, the present application adopts a method of generating a multi-layer non-uniform virtual compensation layer mesh by extension, to finely compensate for the stress changes at the boundary of the test piece. This method extends multiple calculation regions on the basis of the real boundary of the test piece, forming a structure similar to a "buffer zone", so that the boundary conditions of the calculation region can be closer to the real situation, thereby reducing the calculation error and improving the simulation accuracy.

[0033] Further, the layering density of the generated multi-layer non-uniform virtual compensation layer mesh is dynamically adjusted according to the preset seismic frequency spectrum, specifically: fine meshing is adopted in the high-frequency sensitive area, and sparse extended meshing is adopted in the low-frequency area, forming a layered structure that continuously transitions with the real boundary impedance.

[0034] It should be noted that after the boundary compensation region is determined, the boundary of the test piece needs to be compensated by multi-layer non-uniform meshing. In traditional finite element analysis, the boundary conditions of the test piece are usually simplified, such as directly setting fixed boundaries, free boundaries, or elastic support boundaries, etc. However, due to the complexity of the boundary conditions of ceramic materials, and the difficulty of accurately modeling their real boundary behavior under high-frequency vibration, using fixed or free boundaries can result in large simulation errors.

[0035] The present application uses a method of extension, i.e. adding multiple virtual compensation layers outside the real boundary of the test piece, and using different density meshing strategies, so that the compensation layer can simulate the gradual change characteristics of the real boundary conditions. For example, the compensation layer closest to the test piece boundary uses smaller mesh elements to capture subtle stress changes, while the compensation layer far from the test piece uses larger mesh elements to reduce the amount of calculation while ensuring the gradual nature of the boundary. In addition, this non-uniform meshing method can effectively reduce the influence of boundary reflection, making the simulation calculation more stable. The specific operation is as follows: first, calculate the boundary curvature distribution of the test piece according to its shape to determine the areas that need to be compensated. Then, extend multiple mesh layers outside these areas and set the element size of each layer. Generally, the size of the mesh element will gradually increase with the distance, for example, the first layer of mesh element size near the test piece is set to 0.1mm, the second layer is set to 0.2mm, the third layer is set to 0.4mm, and so on. This hierarchical incremental method can effectively smooth the boundary transition and reduce the reflection of stress waves at the boundary, thereby improving the simulation accuracy.

[0036] For example, the boundary curvature of the test piece is usually calculated by the curvature radius method or the second derivative method. If the boundary is discrete point data, the curvature can be approximately calculated by the finite difference method; when the local curvature of the boundary is greater than the curvature threshold, it means that the area may have a strong stress concentration effect and needs to be compensated. The high curvature area is screened out by the threshold, and the boundary grid is encrypted around it to reduce the boundary distortion error.

[0037] The purpose of grid expansion is to form a series of compensation layers outside the boundary of the test piece, so that the stress transfer is smoother and the boundary effect in simulation calculation is reduced. The principles of grid expansion are as follows: according to the target accuracy requirement and the limitation of computing resources, usually set 3-6 layers; set the thickness of each layer in a decreasing relationship, use exponential decay method, for example:

[0038] t n =t1×e -k(n-1)

[0039] Where t n is the thickness of the nth compensation layer, t1 is the thickness of the first compensation layer, and k is the attenuation coefficient.

[0040] Further, the extension of the plurality of grid layers includes the following contents: the grid expansion adopts a non-uniform quadrilateral / hexahedral grid generation strategy, and the steps are as follows:

[0041] The real boundary of the test piece is meshed to ensure that the boundary curvature of the initial grid matches the original test piece; the normal direction of each grid point is calculated, which can be adjusted by the Laplace smoothing algorithm to avoid sharp transition areas, and the compensation layer is expanded according to the above exponential decay method; subsequently, the grid density can be increased in the high-frequency region according to the vibration frequency spectrum characteristics to ensure the continuity of stress transfer.

[0042] Preferably, when constructing the virtual compensation layer, in addition to considering the change of grid density, it also needs to be dynamically adjusted according to the vibration frequency spectrum characteristics of the test piece, because different vibration frequencies will cause the propagation characteristics of stress waves in the material to change. For example, when the vibration frequency is low, the wavelength of the stress wave is long, so a relatively sparse grid division can be used, while when the vibration frequency is high, the wavelength of the stress wave is short, and a more fine grid division is needed to ensure the calculation accuracy.

[0043] The application dynamically optimizes the grid density by analyzing the response characteristics of the test piece at different frequencies. Specifically, before the experiment, the test piece is first tested for excitation scanning to obtain its vibration spectrum characteristics, and the distribution of high-frequency sensitive areas and low-frequency areas is analyzed. For example, if the test piece shows significant stress gradient changes in the frequency range above 50MHz, then in the construction of the compensation layer, higher density grid division is needed in the area corresponding to this frequency band. The specific operation is as follows, the application realizes dynamic adjustment through the following steps:

[0044] The vibration response of the test piece at different frequencies is measured by using a laser vibration meter or a high-frequency strain gauge, and a vibration spectrum diagram is drawn; through frequency spectrum analysis, it is determined which frequency band is the area with the most severe stress change. For example, if it is found that the stress gradient changes greatly above 100MHz, then higher density grid should be used in this area; in the grid generation process of the compensation layer, according to the analysis result, fine grid division (such as 0.1mm grid unit) is used in the high-frequency sensitive area, and sparse extended grid (such as 0.5mm grid unit) is used in the low-frequency area, thereby forming an adaptive non-uniform grid structure.

[0045] For example, the high-frequency sensitive area (>1000Hz): the stress gradient changes rapidly, and fine grid should be used; the low-frequency area (<100Hz): the stress changes slowly, and sparse grid is used; the transition area (100Hz-1000Hz): the grid size decreases layer by layer to ensure the balance between accuracy and calculation efficiency, wherein the grid size setting formula can be:

[0046] d n =d1×e -m(n-1)

[0047] Wherein, d n is the grid unit size of the nth layer, d1 is the first layer grid size, and m is a control parameter adjusting the grid density decay rate.

[0048] Through this method, the application can effectively optimize the grid division, so that it can more accurately match the vibration characteristics of the test piece, thereby improving the accuracy of stress calculation and reducing the error caused by unreasonable grid division. In addition, this method can also reduce the calculation cost, because using larger grid units in the low-frequency area can reduce the calculation amount and improve the simulation efficiency.

[0049] After the construction of the multi-layer virtual compensation layer is completed, it is necessary to ensure that the structure can smoothly transition with the real boundary impedance of the test piece. The continuity of the impedance is crucial for simulation calculation, because if there is a mutation in the boundary impedance, it may cause the stress wave to be reflected or distorted at the boundary, affecting the accuracy of the calculation. The present application optimizes the stiffness and damping parameters layer by layer, so that the physical properties of the compensation layer can match the real boundary impedance of the test piece. Through this layer-by-layer optimization method, the mutation of the boundary impedance can be effectively reduced, so that the stress wave can be smoothly transmitted from the test piece to the compensation layer, thereby reducing the calculation error.

[0050] In addition, the present application adopts an adaptive optimization algorithm to dynamically adjust the impedance parameters of the compensation layer to adapt to different vibration conditions. For example, during the vibration test, the system can monitor the propagation of the stress wave in real time and adjust the parameters of the compensation layer according to the feedback information to ensure optimal matching of the boundary conditions. In this way, the accuracy and stability of the simulation can be further improved, and the simulation results are closer to the real test data.

[0051] In the embodiments of the present application, the stress distribution calculation module 200 specifically includes: constructing a stress distribution reference data field according to the partition structure of the compensation layer grid.

[0052] It should be noted that during the simulation or experimental test, due to the non-uniformity of the ceramic material and the boundary effect, the measured stress data may differ from the theoretical stress distribution. In order to quantify this deviation, a reference data field is needed as a reference. The reference data field provides an ideal state of stress distribution, which facilitates subsequent residual error calculation and correction.

[0053] Preferably, constructing a stress distribution reference data field according to the partition structure of the compensation layer grid includes the following contents:

[0054] First, according to the partition structure of the compensation layer grid, the test piece area is divided into a plurality of stress calculation sub-regions, each region corresponding to a grid element; the boundary conditions for stress field calculation are set, including loading direction, material properties, boundary impedance matching and other parameters; the finite element simulation method is used to solve the stress field distribution of the ceramic test piece under the given boundary conditions; the calculated stress distribution data is mapped to the compensation layer grid to form a discrete reference data field. An interpolation algorithm (such as bilinear interpolation, spline interpolation) is used to optimize the data accuracy to adapt to the density changes of different grid regions.

[0055] It should be noted that the setting of the stress field calculation region is the basis for the construction of the entire reference data field, and the calculation region needs to ensure that the entire specimen range and the extension compensation layer are included to ensure calculation accuracy. The traditional method usually uses uniform grid division of the specimen region, but this method may result in insufficient calculation accuracy in high stress gradient regions and redundant calculation in low stress gradient regions. The present application dynamically divides the grid according to the stress change rate and frequency characteristics, so that fine grids are used in high stress gradient regions and coarse grids are used in low stress gradient regions to improve calculation efficiency and accuracy. According to the stress condition of the specimen, different directions of mechanical loading are set (such as uniaxial compression, three-point bending, etc.).

[0056] Further, the calculation of stress is carried out by arranging strain gauges on the surface of the ceramic specimen, measuring the strain, and then performing stress-strain relationship according to the measured strain. In the conventional operation, a uniform arrangement is usually used, i.e. strain gauges are pasted on the surface of the specimen at equal intervals, which is suitable for uniform stress distribution specimens, but may not be sufficient for stress concentration regions. The present application increases the strain gauge arrangement density in the high stress gradient region in combination with the reference stress data field to improve the measurement accuracy, and uses biaxial or triaxial strain gauges to measure strain information in different directions to improve data integrity. The strain data measured by the strain gauges can be used to calculate the stress.

[0057] For example, the elastic modulus and Poisson's ratio of the ceramic material are first obtained, which determine the stress-strain relationship of the material; the strain data in different directions are obtained from the biaxial or triaxial strain gauges, including the principal strain and shear strain; according to the mechanical behavior of the material, the appropriate stress-strain relationship (such as linear elastic model) is used, and in one-dimensional condition, Hooke's law can be directly used, and in two-dimensional or three-dimensional condition, generalized Hooke's law is needed, combined with Poisson's effect to calculate the stress components in each direction; the multi-axial strain data are processed to calculate the principal stress and shear stress distribution, and the stress concentration region is determined.

[0058] It can be seen that the present application improves the accuracy and simulation efficiency of stress calculation by dynamically optimizing the grid density and boundary impedance matching of the compensation layer, uses adaptive grid division to improve the calculation accuracy of high-frequency sensitive regions, while reducing the calculation redundancy of low-frequency regions, improves the overall calculation efficiency, further optimizes the stiffness and damping parameters of the compensation layer to make the stress wave propagation smoother and reduce the boundary error. In addition, the strain gauge arrangement is optimized in combination with the reference stress data field to improve the measurement accuracy, ensure that the stress calculation result is closer to the true situation, effectively reduce the calculation error, improve the simulation reliability, and reduce the calculation cost.

[0059] Further, in the finite element simulation or actual test process, the boundary conditions of the ceramic test piece are usually not ideal. For example, the test piece edge may have local stress anomalies due to material inhomogeneity, making the actual stress field inconsistent with the theoretical calculation, the fixing device, test fixture, etc. may cause additional constraint forces, thereby changing the stress distribution, the discretization method of the finite element grid may cause stress anomalies in the boundary transition area, and the boundary compensation strategy needs to be adjusted. In order to correct these problems, an optimal boundary adjustment force needs to be calculated and fed back to the compensation device, so that the boundary conditions of the virtual compensation layer are as close to the theoretical ideal boundary as possible.

[0060] The traditional method usually uses Newton iteration or gradient descent method for boundary adjustment, but these methods may have the following problems: the convergence speed of Newton iteration is slow, especially in high-dimensional problems, the calculation amount is huge; the step size selection of gradient descent method is difficult, and it is easy to fall into local optimum, resulting in unstable boundary adjustment.

[0061] The conjugate gradient iteration method is adopted in the reverse boundary correction module 300, which combines the direction optimization strategy of gradient descent, can maintain a faster convergence speed in large-scale matrix operation, and avoid local optimal trap, so that the calculated boundary adjustment force is more accurate, as shown in Figure 2 The boundary adjustment force calculation unit 301 is used to calculate the optimal boundary adjustment force under the boundary conditions; the virtual compensation layer grid parameter adjustment unit 302 is used to dynamically adjust the stiffness and damping parameters of the virtual compensation layer grid according to the calculated optimal boundary adjustment force, so that it is more consistent with the ideal boundary conditions; the stress distribution reference data field updating unit 303 is used to recalculate and update the stress distribution reference data field after the compensation layer parameter adjustment is completed, to ensure that the subsequent stress analysis is based on the latest optimized state.

[0062] In this embodiment, the conjugate gradient iteration method is used in the boundary adjustment force calculation unit 301 to calculate the optimal boundary adjustment force, including: the boundary adjustment force satisfies the linear system, and the conjugate gradient method is used to solve the optimal solution, that is, the optimal boundary adjustment force.

[0063] Preferably, the core idea of the conjugate gradient iteration method is to gradually tend to the optimal by repeatedly adjusting the stress state of the boundary area. It can efficiently search for the possible adjustment direction and avoid falling into local optimum in the multi-dimensional calculation process, so as to find the boundary adjustment force that meets the requirements more quickly and accurately.

[0064] In actual operation, the conjugate gradient iteration method is adopted to gradually optimize the boundary adjustment force: first, an initial estimated value of the boundary adjustment force is set. This initial value can be derived from theoretical calculation, existing experimental data, or preliminary stress prediction results automatically generated by the computer; next, the residual stress error corresponding to the current boundary adjustment force is evaluated. This error reflects the deviation between the current boundary condition and the ideal target. By analyzing the difference between the stress distribution reference data field and the actual stress data, the area that needs to be optimized is found; then, the conjugate gradient is used to search for the optimal adjustment direction. In this process, the system does not simply adjust along the gradient of the current error, but considers multiple historical adjustment directions to avoid the calculation result falling into a local extreme point; after each iteration, the system calculates a new boundary adjustment force and updates the stress residual value. If the new adjustment force makes the stress field closer to the ideal state, the adjustment will continue along the optimization direction until the error of the adjustment force is reduced to an acceptable range.

[0065] Compared with traditional methods, the optimal boundary adjustment scheme can be found more efficiently, avoiding adjustment errors caused by insufficient calculation accuracy or incorrect optimization direction. After adopting the conjugate gradient iteration method, the system can converge faster and ensure that the boundary adjustment force is uniformly distributed, so that the boundary conditions of the ceramic test piece are closer to the ideal state, improving the accuracy of the overall stress analysis.

[0066] In the virtual compensation layer grid parameter adjustment unit 302, the calculated optimal boundary adjustment force needs to be applied to the boundary compensation layer of the test piece to dynamically optimize the mechanical parameters of the compensation layer. Directly applying force to a single layer boundary may cause local stress to be too large or compensation to be insufficient, so a multi-layer boundary compensation strategy is adopted to gradually adjust the multi-layer compensation layer to make the stress field transition more smoothly. The operation of the present application includes:

[0067] A multi-layer compensation grid structure is adopted to set the stiffness and damping parameters of different layers respectively, so that the compensation force can be transmitted layer by layer, and finally a smooth transition is achieved. A compensation force decay function is calculated to adjust the stiffness and damping coefficients of each layer of grid to make them transition layer by layer, avoiding sudden changes.

[0068] In the embodiment of the present application, first, the structure of the multi-layer compensation grid is determined; second, the stiffness and damping adjustment values required by each layer of the compensation grid are calculated. In the present application, instead of simply adjusting according to a fixed ratio, the adjustment amount of each layer is dynamically calculated according to the calculation results of the stress distribution and the boundary adjustment force, so that the compensation layer can adapt to the stress characteristics of different regions; then, the adjustment amount is applied and the change of the stress distribution is monitored to confirm whether the adjustment of the stiffness and damping achieves the desired effect. If there is still an error in the adjustment, the system will further optimize the compensation layer parameters until the stress distribution meets the expectation; finally, after the optimization is completed, the stiffness and damping parameters of the compensation layer are recorded for subsequent adjustment, and if the subsequent experiment or calculation finds that the boundary condition has changed, the parameters can be used as reference values.

[0069] For example, according to the compensation force decay function, the stiffness and damping coefficients of each layer of the grid are adjusted to gradually transition from layer to layer, including: first, by comparing the stress distribution reference data field with the current stress state of the compensation layer grid, the stress change trend of different grid layers is determined, and the stress change rate of each layer of the compensation grid is calculated to ensure that the adjustment direction of the stiffness and damping parameters is consistent with the actual stress demand; the adjustment amount of the high stress gradient area is larger, the stiffness needs to be increased to enhance the boundary matching ability, and the damping needs to be moderately increased to reduce the impact of the sudden change of the adjustment force; the adjustment amount of the low stress gradient area is smaller, and the stiffness and damping change is relatively gentle to ensure the uniformity of the stress distribution. The stiffness adjustment includes considering the stress residual after adjustment and combining the compensation force decay function to make the adjustment amount gradually decay between different compensation layers. The size of the adjustment amplitude depends on the relative position of the current compensation layer and the adjustment result of the previous layer to ensure that the stiffness change does not suddenly change. When adjusting the damping, the damping coefficient is moderately increased according to the direction of the adjustment force to reduce the oscillation effect in the high stress gradient area. At the same time, in the low stress gradient area, the damping adjustment is small to maintain the stable transition of the boundary.

[0070] For example, the compensation force decay function can be expressed as:

[0071] F comp,i = F opt × e -λi

[0072] Where F opt is the optimal boundary adjustment force, λ is the decay coefficient, and i is the grid layer number.

[0073] The stress distribution reference data field updating unit 303 applies the adjusted parameters to the compensation layer and recalculates the stress distribution reference data field to meet the new boundary conditions.

[0074] It should be noted that the conventional boundary compensation method usually adopts single-layer stiffness adjustment, which has obvious defects: if the compensation force is directly applied at the boundary, it is easy to produce a larger stress mutation in this area, resulting in an increase in calculation error, and even affecting the accuracy of the experiment or simulation. Therefore, the present application adopts a multi-layer grid compensation strategy, so that the boundary adjustment force can be attenuated layer by layer to achieve a more stable transition.

[0075] The present application calculates the optimal boundary adjustment force by using the conjugate gradient iteration method, so that the boundary optimization process is more efficient and the local optimal problem is avoided. At the same time, through the multi-layer compensation grid structure, the compensation force can be gradually transitioned, avoiding stress mutation and improving the calculation accuracy and stability of boundary compensation. The two optimization strategies work together to make the present application have higher precision, faster convergence speed and better adaptability in stress analysis and boundary compensation.

[0076] The dynamic data iteration module 400 collects the corrected stress data, adaptively weights the historical stress data, and tracks the stress evolution trend to ensure high matching degree of experimental conditions and real environment. As shown in Figure 3 The dynamic data iteration module 400 includes a data iteration unit 401, which includes real-time collection and dynamic adjustment of stress data of the compensation layer grid and the specimen; a stress evolution trend analysis unit 402, which is used to realize long-term tracking of stress change trend by combining time series analysis, and ensure the stability and adaptability of the compensation layer grid.

[0077] During the dynamic data iteration process, the stress data of the compensation layer grid and the specimen inside need to be collected in real time first to ensure that all stress changes can be accurately monitored and analyzed, and the local stress value is calculated through the stress-strain relationship.

[0078] After data collection, real-time data fusion and dynamic adjustment are needed to ensure that the test conditions adaptively optimize with the changes in stress distribution. In the present application, the data iteration unit 401 uses an adaptive weighted fusion algorithm to dynamically weight the current measured stress data and the historical stress data to obtain a more accurate stress distribution state. The adaptive weighted fusion technology used in the present application dynamically adjusts the weight of the historical data in the calculation process, ensuring that the influence weight of the latest measured data decreases over time, while still retaining the contribution of past data to trend analysis. For example, when the stress data fluctuates dramatically, the weight of recent data will automatically increase to highlight the current working condition change; in stable working conditions, the historical data is mainly used as a reference, making the overall analysis more stable and reliable.

[0079] In addition, the dynamic adjustment strategy is also reflected in the optimization of test loading parameters, such as adaptive adjustment of loading frequency or amplitude for different vibration conditions. Specifically, at the initial stage of the test, the loading parameters are applied according to the preset vibration frequency spectrum; but as the stress data is continuously updated, the system can automatically adjust the loading strategy to optimize the uniformity of stress distribution and reduce boundary errors.

[0080] Further, tracking the stress evolution trend is a key link to ensure the long-term stable operation of the compensation layer grid. The change of stress data not only reflects the mechanical properties of the test piece under different loading conditions, but also reveals the adaptability of the compensation layer grid in long-term operation. Therefore, the main task of this unit is to track the stress data over a long period of time based on time series analysis method, judge the adaptability of the compensation layer grid, and trigger other modules for adjustment when necessary.

[0081] In the traditional finite element simulation method, researchers usually focus on the stress distribution at a certain time of the test, ignoring the evolution characteristics of stress over time. However, ceramic materials have certain time-dependent properties, and their stress distribution may change slowly over time, while the damping and stiffness parameters of the compensation layer may also drift over a long period of time. To solve this problem, the invention uses time series analysis technology to store the collected stress data in chronological order, and predicts the stress change through trend fitting method to judge whether the compensation layer grid can still effectively match the stress distribution of the test piece.

[0082] In the invention, the time series analysis method combines sliding window filtering and autoregressive integrated moving average (ARIMA) model to ensure the analysis accuracy of stress change trend. Sliding window filtering is used to eliminate noise in the data to avoid accidental errors interfering with the analysis results, while the ARIMA model is used to fit the long-term stress evolution trend to predict the future stress distribution state. For example, in high-frequency stress areas, the system uses a shorter time window to respond more quickly to stress fluctuations, while in low-frequency stress areas, a longer time window is used to ensure data stationarity.

[0083] The results of trend analysis are not only used to evaluate the adaptability of the current compensation layer grid, but also as a basis for subsequent optimization decisions. For example, if the stress data in a certain area deviates from the baseline data field for a long time, it indicates that the compensation layer parameters need to be adjusted, at which time the system triggers the reverse boundary correction module to recalculate the boundary adjustment force and dynamically optimizes the compensation layer grid. In addition, if the trend analysis finds that the overall stress distribution of the test piece tends to be stable, the system can appropriately reduce the loading adjustment frequency to save computing resources and improve test efficiency.

[0084] Finally, the long-term tracking of stress evolution trends ensures the stability and adaptability of the compensation layer grid under different working conditions, enabling the entire test system to remain efficient and reliable in long-term operation. The present application combines dynamic data iteration and time series analysis, not only improving the accuracy of stress data, but also ensuring the optimal matching of the compensation layer under different conditions, thereby enhancing the precision and stability of the entire test system.

[0085] In summary, the multi-modal ceramic material seismic performance and stress distribution dynamic analysis system based on the embodiments of the present application is illustrated, which improves the accuracy of ceramic material seismic performance analysis by multi-layer boundary compensation and dynamic adjustment of grid density, reduces the influence of boundary effect on stress distribution calculation. Using reverse boundary correction, the virtual compensation layer parameters are optimized, making the experimental environment closer to the real stress state, and improving the reliability of stress calculation. Through dynamic data iteration, the fusion of historical data and real-time stress data is realized, improving the stability of stress distribution prediction. Finally, the present application ensures more accurate stress evolution analysis of ceramic materials in complex vibration environment, providing more valuable data support for seismic design and engineering application.

[0086] Figure 4 The flowchart of the multi-modal ceramic material seismic performance and stress distribution dynamic analysis method according to the embodiments of the present application is shown in FIG. 1. Figure 4 As shown in FIG. 1, in the multi-modal ceramic material seismic performance and stress distribution dynamic analysis method, it includes: S1: based on the geometric configuration and loading direction of the test piece, a multi-layer non-uniform virtual compensation layer grid is generated outside the real boundary of the test piece, and the layer density is dynamically adjusted according to the seismic frequency spectrum; the test piece is a ceramic material sample; S2: according to the partition structure of the virtual compensation layer grid, a stress distribution reference data field is constructed; S3: calculate the optimal boundary adjustment force and dynamically adjust the virtual compensation layer grid parameters, after adjustment, update the stress distribution reference data field; S4: collect the corrected stress data, adaptively weighted fusion with historical stress data, and track the stress evolution trend, to ensure high matching degree of experimental conditions and real environment.

[0087] Here, those skilled in the art can understand that the specific operation of each step in the above multi-modal ceramic material seismic performance and stress distribution dynamic analysis method has been described in detail above with reference to the multi-modal ceramic material seismic performance and stress distribution dynamic analysis system of Figures 1 to 3 , and therefore, the repeated description thereof will be omitted.

[0088] Having now described the details of the application, it is to be understood that the application is not to be limited to particular details described herein. Various modifications can be made to the embodiments described and constitutional details can be replaced by other devices and equivalents, without departing from the spirit or scope of the application. It is therefore desired that what is, claimed be determined solely by the appended claims and their legal equivalents and that the application be determined to cover any and all variations within the true spirit and scope of the application based on the teaching herein. The application illustratively described herein suitably can be practiced in the absence of any element or step not specifically disclosed herein. In

[0089] It is to be understood that the application is not limited to particular details described herein and is capable of various modifications and alternative constructions, all of which are intended to be included within the scope of the application. The application is not limited to particular structures, aspects, or methods described herein and includes variations and modifications that occur to those skilled in the art. The scope of the application is limited only by the claims.

Claims

1. A system for dynamic analysis of the seismic performance and stress distribution of a multi-modal ceramic material, characterized in that it comprises: The application relates to a multi-layer boundary compensation device module, a stress distribution calculation module, a reverse boundary correction module and a dynamic data iteration module. The multi-layer boundary compensation device module generates a multi-layer non-uniform virtual compensation layer grid outside the real boundary of a test piece according to the geometric configuration and the loading direction of the test piece; the test piece is a ceramic material sample; the layered density is dynamically adjusted according to a vibration frequency spectrum; the geometric configuration is the shape of the ceramic material test piece; the loading direction is external force action; the generation of the multi-layer non-uniform virtual compensation layer grid comprises the following steps: determining a boundary compensation area according to the geometric configuration and the loading direction; calculating boundary curvature distribution according to the geometric configuration of the test piece to determine an area that needs to be compensated; carrying out grid division on the real boundary of the test piece to ensure that the boundary curvature of the initial grid matches the test piece; calculating the normal direction of each grid point and adjusting the grid node distribution by adopting a Laplace smoothing algorithm; and expanding the compensation layer according to an exponential decreasing method. The stress distribution calculation module comprises a boundary adjustment force calculation unit, a virtual compensation layer grid parameter adjustment unit, a stress distribution reference data field updating unit and a stress data acquisition unit. The reverse boundary correction module calculates an optimal boundary adjustment force and dynamically adjusts the parameters of the virtual compensation layer grid; after the adjustment is completed, the stress distribution reference data field is updated. The dynamic data iteration module collects the corrected stress data, adaptively and weightedly fuses the stress data with historical stress data, tracks the stress evolution trend and ensures high matching degree between the experimental conditions and the real environment. The stress distribution calculation module comprises a boundary adjustment force calculation unit, a virtual compensation layer grid parameter adjustment unit, a stress distribution reference data field updating unit and a stress data acquisition unit. The optimal boundary adjustment force is obtained by using a conjugate gradient method. The dynamic adjustment of the stiffness and damping parameters of the virtual compensation layer grid comprises the following steps: adopting a multi-layer compensation grid structure to respectively set the stiffness and damping parameters of different layers; dynamically calculating the adjustment amount of each layer according to the calculation results of the stress distribution and the optimal boundary adjustment force; applying the adjustment amount and monitoring the change of the stress distribution to confirm whether the adjustment of the stiffness and damping reaches an ideal effect.

2. The multi-modal ceramic material shock resistance and stress distribution dynamic analysis system of claim 1, wherein, ​ 3. The multi-modal ceramic material shock resistance and stress distribution dynamic analysis system of claim 1, wherein, ​ 4. The multi-modal ceramic material shock resistance and stress distribution dynamic analysis system of claim 1, wherein, ​ ​ 5. The multi-modal ceramic material shock resistance and stress distribution dynamic analysis system of claim 1, wherein, ​ 6. The multi-modal ceramic material shock resistance and stress distribution dynamic analysis system of claim 5, wherein, ​ 7. The multi-modal ceramic material shock resistance and stress distribution dynamic analysis system of claim 6, wherein, The dynamic calculation of the adjustment amount of each layer comprises: comparing the stress distribution reference data field with the current stress state of the compensation layer grid to determine the stress change trend of different grid layers; calculating the stress change rate of each layer of the compensation grid to ensure that the adjustment direction of the stiffness and damping parameters is consistent with the actual stress demand; the stiffness adjustment requires the adjustment amount to gradually attenuate between different compensation layers, and the size of the adjustment amplitude depends on the relative position of the current compensation layer and the adjustment result of the previous layer, so as to ensure that the stiffness change does not suddenly change; when adjusting the damping, the damping coefficient is increased according to the action direction of the adjustment force, and the oscillation effect of the high stress gradient area is reduced. 8.The system for dynamic analysis of shock resistance and stress distribution of multi-modal ceramic materials according to claim 7, wherein, The tracking of the stress evolution trend combines sliding window filtering and an autoregressive integral moving average model; the sliding window filtering is used to eliminate noise in the data and avoid accidental errors from interfering with the analysis results; The autoregressive integral moving average model is used to fit the long-term stress evolution trend and predict the future stress distribution state.

9. A method for dynamic analysis of the seismic performance and stress distribution of a multi-modal ceramic material, characterized by, Comprise: Based on the geometric configuration and loading direction of the test piece, a multi-layer non-uniform virtual compensation layer grid is generated by extending the real boundary of the test piece, and the layered density is dynamically adjusted according to the seismic frequency spectrum; The test piece is a ceramic material sample; according to the partition structure of the virtual compensation layer grid, a stress distribution reference data field is constructed; the optimal boundary adjustment force is calculated and the parameters of the virtual compensation layer grid are dynamically adjusted, after the adjustment is completed, the stress distribution reference data field is updated; the corrected stress data is collected, adaptively weighted and fused with historical stress data, and the stress evolution trend is tracked to ensure high matching degree of experimental conditions and real environment; The geometric configuration is the shape of the ceramic material test piece; The loading direction is the external force action; The generation of the multi-layer non-uniform virtual compensation layer grid comprises: determining the boundary compensation area according to the geometric configuration and the loading direction; calculating the boundary curvature distribution according to the geometric configuration of the test piece to determine the area that needs to be compensated; dividing the real boundary of the test piece into grids to ensure that the boundary curvature of the initial grid matches the test piece; calculating the normal direction of each grid point and adjusting the grid node distribution by using the Laplace smoothing algorithm; expanding the compensation layer according to the exponential decreasing method.

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