Method and system for dynamically analyzing anti-seismic property and stress distribution of multi-modal ceramic material

Abstract

The invention provides a multi-mode ceramic material anti-seismic property and stress distribution dynamic analysis method and system, and relates to the field of dynamic analys.The method comprises the steps that based on the geometrical configuration and the loading direction of a test piece, multiple layers of non-uniform virtual compensation layer grids are generated on the true boundary extension of the test piece, and the layering density is dynamically adjusted according to a seismic spectrum diagram; 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 the optimal boundary adjusting force, dynamically adjusting the grid parameters of the virtual compensation layer, and updating the stress distribution reference data field after the adjustment is completed; the method comprises the following steps: acquiring corrected stress data, carrying out adaptive weighted fusion on the corrected stress data and historical stress data, and tracking a stress evolution trend, so that high matching degree of experimental conditions and a real environment is ensured, and stress evolution analysis of the ceramic material in a complex vibration environment is more accurate; and data support with higher reference value is provided for aseismic design and engineering application.

Description

Technical Field

[0001] The present invention relates to the field of dynamic analysis, and more specifically, to a method and system for dynamically analyzing the seismic performance and stress distribution of multimodal ceramic materials. Background Art

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

[0003] There are still many deficiencies in the existing technology for analyzing the seismic performance and stress distribution of ceramic materials. On the one hand, traditional test methods have limitations in simulating actual boundary conditions. Specimens are usually fixed with rigid fixtures, which, although providing good repeatability, cannot truly reproduce the boundary constraint effect of ceramic structures under complex working conditions, thus affecting the reliability of experimental data. On the other hand, current stress analysis methods mainly based on static or quasi-static loading modes fail to fully consider the dynamic influence of vibration spectra, resulting in experimental results that are difficult to comprehensively reflect the long-term service state of ceramic materials in real vibration environments. Summary of the Invention

[0004] To solve the above technical problems, the present invention is proposed. The present invention provides a method and system for dynamically analyzing the seismic performance and stress distribution of multimodal ceramic materials.

[0005] According to one aspect of the present invention, there is provided a system for dynamically analyzing the seismic performance and stress distribution of multimodal ceramic materials, which includes:

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

[0007] A stress distribution calculation module, which constructs a stress distribution reference data field based on the partition structure of the virtual compensation layer grid;

[0008] A reverse boundary correction module, which calculates the 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;

[0009] The dynamic data iteration module collects the corrected stress data, performs adaptive weighted fusion with the historical stress data, and tracks the stress evolution trend to ensure a high degree of match between the experimental conditions and the real environment.

[0010] Furthermore, the geometric configuration is the shape of a ceramic material specimen; the loading direction is the action of an external force; the generation of the multi-layer non-uniform virtual compensation layer grid includes: determining the boundary compensation area based on the geometric configuration and the loading direction; calculating the boundary curvature distribution based on the geometric configuration of the specimen, and determining the area that needs to be compensated; gridding the actual boundary of the specimen to ensure that the boundary curvature of the initial grid matches the specimen; calculating the normal direction of each grid point, and adjusting the grid node distribution using the Laplace smoothing algorithm; and expanding the compensation layer according to the exponential decrease method.

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

[0012] Furthermore, the construction of the stress distribution reference data field includes: dividing the specimen area into multiple 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 the finite element simulation method to solve the stress field distribution of the ceramic specimen under given boundary conditions; mapping the calculated stress distribution data to the compensation layer grid to form a discretized reference data field.

[0013] Furthermore, the stress distribution calculation module includes a boundary adjustment force calculation unit, which calculates the optimal boundary adjustment force based on the boundary conditions; a virtual compensation layer grid parameter adjustment unit, which is used to dynamically adjust 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, which is used to recalculate and update the stress distribution reference data field after completing the compensation layer parameter adjustment.

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

[0015] Furthermore, the dynamic adjustment of the stiffness and damping parameters of the virtual compensation layer grid includes: adopting a multi-layer compensation grid structure to set the stiffness and damping parameters of different layers respectively; 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 changes in 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 for each layer includes: 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 compensation grid layer to ensure that the adjustment directions of the stiffness and damping parameters are consistent with the actual stress requirements; for the stiffness adjustment, it is required that the adjustment amount gradually decays between different compensation layers, and the magnitude 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 mutate; for the damping adjustment, according to the acting direction of the adjustment force, increase the damping coefficient to reduce the oscillation effect in the high stress gradient region.

[0017] Further, the tracking of the stress evolution trend combines a sliding window filter and an autoregressive integrated moving average model; the sliding window filter is used to remove the noise in the data to avoid interference of accidental errors on the analysis results; the autoregressive integrated 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, there is provided a method for dynamically analyzing the seismic performance and stress distribution of multi-modal ceramic materials, which includes: based on the geometric configuration and loading direction of the specimen, generating a multi-layer non-uniform virtual compensation layer grid by extending the real boundary of the specimen, and dynamically adjusting the layer density according to the seismic frequency spectrum diagram; the specimen is a ceramic material sample; constructing a stress distribution reference data field according to the partition structure of the virtual compensation layer grid; calculating the optimal boundary adjustment force and dynamically adjusting the parameters of the virtual compensation layer grid, and after the adjustment is completed, updating the stress distribution reference data field; collecting the corrected stress data, performing adaptive weighted fusion with the historical stress data, and tracking the stress evolution trend to ensure a high degree of matching between the experimental conditions and the real environment.

[0019] Compared with the prior art, the present invention improves the accuracy of the seismic performance analysis of ceramic materials and reduces the influence of boundary effects on the stress distribution calculation through multi-layer boundary compensation and dynamic adjustment of the grid density; uses reverse boundary correction to optimize the parameters of the virtual compensation layer, making the experimental environment closer to the real stress state and enhancing the reliability of the stress calculation; realizes the fusion of historical data and real-time stress data through dynamic data iteration, improving the stability of the stress distribution prediction. Finally, the present invention ensures more accurate stress evolution analysis of ceramic materials in a complex vibration environment, providing more valuable data support for seismic design and engineering applications. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for the description of the embodiments or the prior art. Obviously, the drawings in the following description are some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings. In the drawings:

[0021] Figure 1 It is a system block diagram of a dynamic analysis system for the seismic performance and stress distribution of a multimodal ceramic material according to an embodiment of the present invention.

[0022] Figure 2 It is a block diagram of a reverse boundary correction module in a dynamic analysis system for the seismic performance and stress distribution of a multimodal ceramic material according to an embodiment of the present invention.

[0023] Figure 3 It is a block diagram of a dynamic data iteration module in a dynamic analysis system for the seismic performance and stress distribution of a multimodal ceramic material according to an embodiment of the present invention.

[0024] Figure 4 It is a flowchart of a dynamic analysis method for the seismic performance and stress distribution of a multimodal ceramic material according to an embodiment of the present invention. Detailed Embodiments

[0025] Next, exemplary embodiments of the present invention will be described in detail with reference to the drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all of the embodiments of the present invention. It should be understood that the present invention is not limited by the exemplary embodiments described herein.

[0026] As mentioned in the above background art, there are still many deficiencies in the analysis of the seismic performance and stress distribution of ceramic materials in the prior art. On the one hand, traditional test methods have limitations in simulating actual boundary conditions. Specimens are usually fixed by rigid fixtures. Although this method can provide good repeatability, it cannot truly reproduce the boundary constraint effect of the ceramic structure under complex working conditions, thus 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 comprehensively reflect the long-term service state of ceramic materials in a real vibration environment. The present invention proposes a dynamic analysis system for the seismic performance and stress distribution of multimodal ceramic materials, including:

[0027] Figure 1 It is a system block diagram of a dynamic analysis system for the seismic performance and stress distribution of a multimodal ceramic material according to an embodiment of the present invention. As Figure 1 shown, in the dynamic analysis system for the seismic performance and stress distribution of a multimodal ceramic material, it includes:

[0028] The multi-layer boundary compensation device module 100 generates a multi-layer non-uniform virtual compensation layer grid by extending the real boundary of the specimen based on the geometric configuration and loading direction of the specimen, and the layering density is dynamically adjusted according to the shock frequency spectrum diagram; the stress distribution calculation module 200 constructs a stress distribution reference data field based on 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. After the adjustment is completed, the stress distribution reference data field is updated; the dynamic data iteration module 400 collects the corrected stress data, performs adaptive weighted fusion with the historical stress data, and tracks the stress evolution trend to ensure a high degree of matching between the experimental conditions and the real environment.

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

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

[0031] Before constructing the multi-layer boundary compensation device, it is first necessary to clarify the geometric configuration and loading direction of the specimen. This is because when the ceramic material is subjected to vibration or impact loads, its stress distribution will be affected by the shape, boundary constraints, and load application method. The geometric configuration refers to the shape of the ceramic material specimen (such as rectangular, circular, irregular, etc.). When different shapes are subjected to external forces, the stress concentration at the boundary will be different. For example, stress concentration often occurs at the corners of rectangular specimens, while circular specimens have a relatively uniform stress distribution at the edges. In addition, the loading direction determines the way of stress transfer. For example, when loading in the vertical direction, mainly compressive deformation occurs, while when loading in the horizontal direction, shear stress may be caused. Therefore, when constructing the boundary compensation structure, it is necessary to determine the boundary compensation area according to the geometric configuration and loading direction, that is, to identify which parts are likely to cause calculation errors in the vibration test and construct virtual compensation layers at these parts.

[0032] Finite element analysis is usually performed using uniform meshing, but this method can lead to insufficient calculation accuracy, especially stress errors may occur at the boundaries. To address this problem, the present invention uses a method of generating a multi-layer non-uniform virtual compensation layer mesh by extension to finely compensate for stress changes at the specimen boundary. This method forms a structure similar to a "buffer zone" by expanding multiple calculation areas based on the actual boundaries of the specimen, so that the boundary conditions of the calculation area can be closer to the actual situation, thereby reducing calculation errors and improving simulation accuracy.

[0033] Furthermore, the layered density of the generated multi-layer non-uniform virtual compensation layer grid is dynamically adjusted according to the preset seismic spectrum. Specifically, the high-frequency sensitive area is divided into fine grids, and the low-frequency area is divided into sparse extended grids to form a layered structure with continuous transition to the real boundary impedance.

[0034] It should be noted that after determining the boundary compensation area, multi-layer non-uniform grid compensation is required for the specimen boundary. In traditional finite element analysis, the boundary conditions of the specimen are usually simplified, such as directly setting fixed boundaries, free boundaries, or elastic support boundaries. However, since the boundary conditions of ceramic materials are often more complex and their true boundary behavior is difficult to accurately model under high-frequency vibration, the use of fixed or free boundaries may lead to large simulation errors.

[0035] The present invention adopts an extension method, that is, multiple virtual compensation layers are added outside the real boundary of the specimen, and a grid division strategy with different densities is adopted, so that the compensation layer can simulate the gradual characteristics of the real boundary conditions. For example, the compensation layer closest to the specimen boundary adopts a smaller grid unit to capture subtle stress changes, while the compensation layer far away from the specimen adopts a larger grid unit to reduce the amount of calculation and ensure the gradual change of the boundary. In addition, this non-uniform grid division method can effectively reduce the influence of boundary reflection, making the simulation calculation more stable. The specific operation is as follows: First, according to the shape of the specimen, the boundary curvature distribution is calculated to determine the area that needs to be compensated. Then, multiple grid layers are extended in these areas, and the unit size of each layer is set. In general, the size of the grid unit will gradually increase with the increase of distance. For example, the size of the first layer of grid units close to the specimen 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, reduce the reflection of stress waves at the boundary, and thus improve the simulation accuracy.

[0036] Exemplarily, the calculation of the specimen boundary curvature is usually solved 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; a curvature threshold is set. When the local curvature of the boundary is greater than this curvature threshold, it means that a strong stress concentration effect may occur in this area, and key compensation is required. The high-curvature areas are screened out by the threshold, and the boundary grid is encrypted around them to reduce the boundary distortion error.

[0037] The purpose of grid expansion is to form a series of compensation layers outside the specimen boundary, making the stress transfer smoother and reducing the boundary effect in the simulation calculation. Among them, the principles of grid expansion are as follows: According to the target accuracy requirements and calculation resource limitations, usually 3 to 6 layers are set; the thickness decreasing relationship of each layer is set, and the exponential decreasing method is adopted. 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] Furthermore, the extension of multiple grid layers includes the following: The grid expansion adopts a non-uniform quadrilateral / hexahedron grid generation strategy, and the steps are as follows:

[0041] The real boundary of the specimen is meshed to ensure that the boundary curvature of the initial grid matches the original specimen; the normal direction of each grid point is calculated, and the Laplace smoothing algorithm can be used to adjust the distribution of grid nodes to avoid sharp transition areas, and the compensation layer is extended according to the above exponential decreasing method; subsequently, according to the vibration spectrum characteristics, the grid density can be increased in the high-frequency region 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 is also necessary to make dynamic adjustments according to the vibration spectrum characteristics of the specimen, because different vibration frequencies will cause changes in the propagation characteristics of stress waves in the material. For example, in the case of low-frequency vibration, the wavelength of the stress wave is long, so a relatively sparse grid division can be used, while in the case of high-frequency vibration, the wavelength of the stress wave is short, and a finer grid division is required to ensure the calculation accuracy.

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

[0044] Laser vibrometers or high-frequency strain gauges are used to measure the vibration response of the specimen at different frequencies and draw vibration spectrum diagrams; through spectrum analysis, determine which frequency bands are the areas with the most drastic stress changes. For example, if it is found that the stress gradient changes greatly in the frequency band above 100MHz, a higher density grid needs to be used in this area; in the grid generation process of the compensation layer, according to the analysis results, 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, in high-frequency sensitive areas (>1000Hz), the stress gradient changes rapidly and a fine grid is required; in low-frequency areas (<100Hz), the stress changes slowly and a sparse grid is used; in transition areas (100Hz-1000Hz), the grid size decreases layer by layer to ensure a balance between accuracy and computational efficiency, wherein the grid size setting formula can be:

[0046] d n =d1×e -m(n-1)

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

[0048] Through this method, the present invention can effectively optimize the grid division so that it can more accurately match the vibration characteristics of the specimen, 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 amount of calculation 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 to the true boundary impedance of the specimen. The continuity of impedance is crucial for simulation calculations because if there are abrupt changes in the boundary impedance, it may cause stress waves to reflect or distort at the boundary, affecting the accuracy of the calculations. The present invention makes the physical properties of the compensation layer match the true boundary impedance of the specimen by optimizing the stiffness and damping parameters layer by layer. By this layer-by-layer optimization method, abrupt changes in the boundary impedance can be effectively reduced, enabling stress waves to smoothly transfer from the specimen to the compensation layer, thereby reducing calculation errors.

[0050] In addition, the present invention uses 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 process, the system can monitor the propagation of stress waves in real time and adjust the parameters of the compensation layer according to the feedback information to ensure the optimal matching of the boundary conditions. In this way, the accuracy and stability of the simulation can be further improved, making the simulation results closer to the real test data.

[0051] In the embodiment 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 process, due to the inhomogeneity of the ceramic material and the boundary effect, the measured stress data may deviate from the theoretical stress distribution. To quantify this deviation, a reference data field is required as a reference. The role of the reference data field is to provide a stress distribution under ideal conditions, facilitating subsequent calculation of residuals and correction.

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

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

[0055] It should be noted that the setting of the stress field calculation area is the basis for constructing the entire reference data field. It is necessary to ensure that the calculation area includes the complete specimen range and the extended compensation layer to ensure the calculation accuracy. Traditional methods usually use uniform grid division for the specimen area, but this method may lead to insufficient calculation accuracy in high-stress gradient areas and redundant calculations in low-stress gradient areas. The present invention dynamically divides the grid according to the stress change rate and frequency characteristics, so that fine grids are used in high-stress gradient areas and coarse grids are used in low-stress gradient areas to improve the calculation efficiency and accuracy. And according to the force condition of the specimen, mechanical loading in different directions (such as uniaxial compression, three-point bending, etc.) is set.

[0056] Furthermore, the stress is calculated by arranging strain gauges on the surface of the ceramic specimen and measuring the strain and then calculating according to the stress-strain relationship. In conventional operations, a uniform arrangement method is usually adopted, and strain gauges are pasted at equal intervals on the surface of the specimen, which is suitable for specimens with uniform stress distribution, but may have insufficient sampling in stress concentration areas. The present invention combines the reference stress data field, increases the density of strain gauge arrangement in high-stress gradient areas to improve the measurement accuracy, uses biaxial or triaxial strain gauges to measure strain information in different directions to improve data integrity, and the strain data measured by the strain gauges can be used to calculate the stress.

[0057] Exemplarily, first obtain the elastic modulus and Poisson's ratio of the ceramic material, which determine the stress-strain relationship of the material; obtain the strain data in each direction from the biaxial or triaxial strain gauges, including the principal strain and shear strain; according to the mechanical behavior of the material, adopt an appropriate stress-strain relationship (such as a linear elastic model), and Hooke's law can be directly used under one-dimensional conditions, and the generalized Hooke's law needs to be used under two-dimensional or three-dimensional conditions, and the stress components in each direction are calculated in combination with the Poisson effect; process the multi-axis strain data, calculate the principal stress and shear stress distributions, and clarify the stress concentration areas.

[0058] It can be seen that the present invention improves the accuracy of stress calculation and the simulation efficiency by dynamically optimizing the grid density of the compensation layer and the boundary impedance matching. By adopting adaptive grid division, the calculation accuracy in high-frequency sensitive areas is improved, while the calculation redundancy in low-frequency areas is reduced, and the overall calculation efficiency is improved; further, by optimizing the stiffness and damping parameters of the compensation layer, the stress wave propagation is made smoother, and the boundary error is reduced. In addition, by optimizing the arrangement of strain gauges in combination with the reference stress data field, the measurement accuracy is improved, ensuring that the stress calculation result is closer to the real situation, effectively reducing the calculation error, improving the simulation reliability, and reducing the calculation cost.

[0059] Furthermore, during finite element simulation or actual testing, the boundary conditions of ceramic specimens usually cannot reach the ideal state. For example, local stress anomalies may occur at the edges of the specimens due to material inhomogeneity, resulting in a mismatch between the actual stress field and the theoretical calculation. Fixtures, test jigs, etc. may cause additional binding forces, thus changing the stress distribution. The discretization method of the finite element mesh may lead to stress anomalies in the boundary transition region, and the boundary compensation strategy needs to be adjusted, etc. 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 can approximate the theoretical ideal boundary as much as possible.

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

[0061] The reverse boundary correction module 300 of the present invention specifically adopts the conjugate gradient iteration method, which combines the direction optimization strategy of gradient descent. It can maintain a relatively fast convergence speed in large-scale matrix operations and avoid local optimum traps, making the calculated boundary adjustment force more accurate. As Figure 2 shown, it includes a boundary adjustment force calculation unit 301 for calculating the optimal boundary adjustment force according to the boundary conditions; a virtual compensation layer mesh parameter adjustment unit 302 for dynamically adjusting the stiffness and damping parameters of the virtual compensation layer mesh according to the calculated optimal boundary adjustment force to make it more in line with the ideal boundary conditions; and a stress distribution reference data field update unit 303 for recalculating and updating the stress distribution reference data field after the parameters of the compensation layer are adjusted to ensure that subsequent stress analysis is based on the latest optimized state.

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

[0063] Preferably, the core idea of the conjugate gradient iteration method is to gradually make the stress state in the boundary region tend to be optimal by repeatedly adjusting it. It can efficiently search for possible adjustment directions and avoid falling into local optima during multi-dimensional calculations, so as to find the boundary adjustment force that meets the requirements more quickly and accurately.

[0064] In the actual operation process, the present invention adopts the conjugate gradient iteration method to gradually optimize the boundary adjustment force: First, set the estimated value of the initial boundary adjustment force. This initial value can be derived from theoretical calculations, existing experimental data, or the preliminary stress prediction results automatically generated by the computer; Next, evaluate the residual stress error corresponding to the current boundary adjustment force. This error reflects the deviation between the current boundary conditions 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, use the conjugate gradient to search for the optimal adjustment direction. In this process, the system does not simply adjust along the gradient of the current error, but comprehensively considers multiple historical adjustment directions to avoid the calculation results falling into local extreme points; After each iteration, the system calculates the new boundary adjustment force and updates the stress residual value. If the new adjustment force makes the stress field closer to the ideal state, continue to adjust along the optimization direction until the error of the adjustment force drops to an acceptable range.

[0065] Compared with the traditional method, it can find the best boundary adjustment scheme more efficiently and avoid adjustment errors caused by insufficient calculation accuracy or wrong optimization direction. After adopting the conjugate gradient iteration method, the system can converge faster and ensure the uniform distribution of the boundary adjustment force, so that the boundary conditions of the ceramic specimen are closer to the ideal state and improve 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 specimen to dynamically optimize the mechanical parameters of the compensation layer. Applying force directly to a single-layer boundary may cause excessive local stress or insufficient compensation. Therefore, a multi-layer boundary compensation strategy needs to be adopted. Through the progressive adjustment of multiple compensation layers, the stress field can be made to transition more smoothly. The operations of the present invention include:

[0067] Adopt a multi-layer compensation grid structure, and set the stiffness and damping parameters of different layers respectively, so that the compensation force can be transmitted layer by layer, and finally achieve a smooth transition. Calculate the compensation force attenuation function, and adjust the stiffness and damping coefficients of each layer of the grid according to the compensation force attenuation function to make it transition layer by layer and avoid sudden changes.

[0068] In an embodiment of the present invention, first, the structure of the multi-layer compensation grid is determined; second, the stiffness and damping adjustment values required for each layer of the compensation grid are calculated. In the present invention, instead of simply adjusting according to a fixed ratio, the adjustment amount of each layer is dynamically calculated based on the stress distribution and the calculation result of 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 reaches the ideal effect. If there is still an error in the adjustment, the system will further optimize the parameters of the compensation layer 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. If it is found in subsequent experiments or calculations that the boundary conditions have changed, these parameters can be used as reference values.

[0069] Exemplarily, adjusting the stiffness and damping coefficients of each layer of the grid to make them transition layer by layer according to the compensation force attenuation function includes: first, 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, and 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 adjustment amount in the high stress gradient area is larger, and the stiffness needs to be increased to enhance the boundary matching ability, and at the same time, the damping is moderately increased to reduce the impact of the sudden change of the adjustment force; the adjustment amount in the low stress gradient area is smaller, and the change of the stiffness and damping 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 attenuation function to make the adjustment amount gradually attenuate 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 change of the stiffness does not mutate. When adjusting the damping, the damping coefficient is moderately increased according to the action 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] Exemplarily, the compensation force attenuation 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 attenuation coefficient, and i is the grid layer number.

[0073] The adjusted parameters are applied to the compensation layer in the stress distribution reference data field update unit 303, and the stress distribution reference data field is recalculated to conform to the new boundary conditions.

[0074] It should be noted that conventional boundary compensation methods usually adopt single-layer stiffness adjustment, which has obvious defects: if the compensation force is directly applied at the boundary, it is very easy to generate large stress mutations in this area, resulting in an increase in calculation errors and even possibly affecting the accuracy of experiments or simulations. Therefore, the present invention adopts a multi-layer grid compensation strategy, enabling the boundary adjustment force to decay layer by layer to achieve a smoother transition.

[0075] The present invention uses the conjugate gradient iteration method to calculate the optimal boundary adjustment force, making the boundary optimization process more efficient and avoiding the local optimum problem. At the same time, through the multi-layer compensation grid structure, the compensation force can be gradually transitioned to avoid stress mutations, improve the calculation accuracy and the stability of boundary compensation. The combined action of these two optimization strategies enables the present invention to have higher accuracy, faster convergence speed and better adaptability in stress analysis and boundary compensation.

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

[0077] During the dynamic data iteration process, it is first necessary to collect the stress data inside the compensation layer grid and the specimen in real time to ensure that all stress changes can be accurately monitored and incorporated into the analysis, and calculate the local stress value through the stress-strain relationship.

[0078] After the data collection is completed, real-time data fusion and dynamic adjustment are required to ensure that the test conditions are adaptively optimized with the change of the stress distribution. In the present invention, the data iteration unit 401 performs dynamic weighted calculation on the currently measured stress data and the historical stress data through the adaptive weighted fusion algorithm to obtain a more accurate stress distribution state. The adaptive weighted fusion technology adopted by our invention enables the historical data to dynamically adjust the weight during the calculation process, ensuring that the influence weight of the latest measured data on the analysis decreases with time, while still retaining the contribution of the past data to the trend analysis. For example, when the stress data fluctuates violently, the weight of the recent data will automatically increase to highlight the current working condition change; under stable working conditions, the historical data is used as the main reference to make the overall analysis more stable and reliable.

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

[0080] Furthermore, 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 specimen under different loading conditions, but also reveals the adaptability of the compensation layer grid during long-term operation. Therefore, the main task of this unit is to track the stress data for a long time based on time series analysis methods, judge the adaptability of the compensation layer grid, and trigger other modules for adjustment when necessary.

[0081] In traditional finite element simulation methods, researchers usually focus on the stress distribution at a certain moment in the test, while ignoring the evolution characteristics of stress over time. However, ceramic materials have a certain time effect, and their stress distribution may change slowly over time, and the damping and stiffness parameters of the compensation layer may also drift due to long-term loading. To solve this problem, the present invention adopts time series analysis technology, stores the collected stress data in chronological order, and predicts the stress change through trend fitting methods to determine whether the compensation layer grid can still effectively match the stress distribution of the specimen.

[0082] In the present invention, the time series analysis method combines moving window filtering and autoregressive integrated moving average (ARIMA) model to ensure the analysis accuracy of the stress change trend. Moving window filtering is used to remove the noise in the data and avoid the interference of accidental errors on 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 the high-frequency stress region, the system will use a shorter time window to respond to stress fluctuations faster, while in the low-frequency stress region, a longer time window will be used to ensure the smoothness of the data.

[0083] The results of trend analysis are not only used to evaluate the adaptability of the current compensation layer grid, but also serve as the basis for subsequent optimization decisions. For example, if the stress data in a certain area deviates from the reference data field for a long time, it means that the compensation layer parameters need to be readjusted. At this time, the system will trigger the reverse boundary correction module to recalculate the boundary adjustment force and dynamically optimize the compensation layer grid. In addition, if trend analysis finds that the overall stress distribution of the specimen 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 the stress evolution trend ensures the stability and adaptability of the compensation layer grid under different working conditions, enabling the entire test system to maintain high efficiency and reliability during long-term operation. By combining dynamic data iteration and time series analysis, the present invention not only improves the accuracy of stress data but also ensures the optimal matching of the compensation layer under different conditions, thereby enhancing the accuracy and stability of the entire test system.

[0085] In summary, a dynamic analysis system for the seismic performance and stress distribution of multi-modal ceramic materials based on the embodiments of the present invention is elucidated. By means of multi-layer boundary compensation and dynamic adjustment of grid density, it improves the accuracy of seismic performance analysis of ceramic materials and reduces the influence of boundary effects on stress distribution calculation. Using reverse boundary correction to optimize the parameters of the virtual compensation layer makes the experimental environment closer to the actual stress state and enhances the reliability of stress calculation. Through dynamic data iteration, the fusion of historical data and real-time stress data is achieved, improving the stability of stress distribution prediction. Finally, the present invention ensures more accurate stress evolution analysis of ceramic materials in complex vibration environments, providing more valuable data support for seismic design and engineering applications.

[0086] Figure 4 FIG. is a flowchart of a dynamic analysis method for the seismic performance and stress distribution of multi-modal ceramic materials according to an embodiment of the present invention. As Figure 4 shown, in the dynamic analysis method for the seismic performance and stress distribution of multi-modal ceramic materials, it includes: S1: Based on the geometric configuration and loading direction of the specimen, a multi-layer non-uniform virtual compensation layer grid is extended outside the real boundary of the specimen, and the hierarchical density is dynamically adjusted according to the seismic frequency spectrum diagram; the specimen 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 parameters of the virtual compensation layer grid. After the adjustment is completed, update the stress distribution reference data field; S4: Collect the corrected stress data, perform adaptive weighted fusion with the historical stress data, and track the stress evolution trend to ensure a high degree of matching between the experimental conditions and the real environment.

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

[0088] In summary, the dynamic analysis method for the seismic performance and stress distribution of the multimodal ceramic material based on the embodiments of the present invention is elucidated. After considering the specification and practicing the embodiments disclosed herein, those skilled in the art will readily conceive of other embodiments of the present application. The present application is intended to cover any variations, uses, or adaptations of the present application, which follow the general principles of the present application and include the common general knowledge or conventional technical means in the technical field not disclosed in the present application.

[0089] It should be understood that the present application is not limited to the exact structures described above and shown in the drawings, and various modifications and changes can be made without departing from its scope. The scope of the present application is only limited by the appended claims.

Claims

1. A dynamic analysis system for the seismic performance and stress distribution of multimodal ceramic materials, characterized in that, include: The 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 specimen, and the layer density is dynamically adjusted according to the seismic spectrum diagram; the specimen is a ceramic material sample; A stress distribution calculation module constructs a stress distribution reference data field according to the partition structure of the virtual compensation layer grid; A reverse boundary correction module calculates the optimal boundary adjustment force and dynamically adjusts the mesh parameters of the virtual compensation layer, and updates the stress distribution reference data field after the adjustment is completed; The dynamic data iteration module collects the corrected stress data, performs adaptive weighted fusion with the historical stress data, and tracks the stress evolution trend to ensure a high degree of match between the experimental conditions and the real environment.

2. The dynamic analysis system for the seismic performance and stress distribution of the multi-modal ceramic material according to claim 1, wherein The geometric configuration is the shape of a ceramic material specimen; the loading direction is the action of an external force; the generation of the multi-layer non-uniform virtual compensation layer grid includes: determining a boundary compensation area according to the geometric configuration and the loading direction; calculating a boundary curvature distribution according to the geometric configuration of the specimen, and determining an area that needs to be compensated in particular; meshing the true boundary of the specimen to ensure that the boundary curvature of the initial grid matches the specimen; calculating the normal direction of each grid point, and adjusting the grid node distribution using the Laplace smoothing algorithm; and expanding the compensation layer according to the exponential decrease method.

3. The dynamic analysis system for the seismic performance and stress distribution of the multimodal ceramic material according to claim 2, characterized in that, The adjustment of the layered density includes: measuring the vibration response of the specimen at different frequencies and drawing a vibration spectrum diagram; dividing the high-frequency sensitive area and the low-frequency area according to spectrum analysis; using a fine grid in the high-frequency sensitive area and a sparse grid in the low-frequency area; in the transition area, the grid size decreases layer by layer.

4. The dynamic analysis system for the seismic performance and stress distribution of the multimodal ceramic material according to claim 1, characterized in that, The construction of the stress distribution reference data field includes: dividing the specimen area into multiple stress calculation sub-areas according to the partition structure of the compensation layer grid, each area corresponds to a grid unit; setting boundary conditions for stress field calculation; using a finite element simulation method to solve the stress field distribution of the ceramic specimen under given boundary conditions; mapping the calculated stress distribution data to the compensation layer grid to form a discretized reference data field.

5. The dynamic analysis system for the seismic performance and stress distribution of the multimodal ceramic material according to claim 1, wherein The stress distribution calculation module includes a boundary adjustment force calculation unit, which calculates the optimal boundary adjustment force based on the boundary conditions; a virtual compensation layer grid parameter adjustment unit, which is used to dynamically adjust the stiffness and damping parameters of the virtual compensation layer grid according to the optimal boundary adjustment force; The stress distribution reference data field updating unit is used to recalculate and update the stress distribution reference data field after completing the compensation layer parameter adjustment.

6. The dynamic analysis system for the seismic performance and stress distribution of the multimodal ceramic material according to claim 1, characterized in that, The optimal boundary adjustment force is solved by using the conjugate gradient method and the optimal solution is obtained by iteration.

7. The dynamic analysis system for seismic performance and stress distribution of the multimodal ceramic material according to claim 6, wherein The method of dynamically adjusting the stiffness and damping parameters of the virtual compensation layer grid includes: adopting a multi-layer compensation grid structure and setting the stiffness and damping parameters of different layers respectively; 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 changes in the stress distribution to confirm whether the adjustment of the stiffness and damping achieves the ideal effect.

8. The dynamic analysis system for the seismic performance and stress distribution of the multimodal ceramic material according to claim 7, characterized in that, The dynamic calculation of the adjustment amount for each layer includes: 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 compensation grid layer to ensure that the adjustment direction of the stiffness and damping parameters is consistent with the actual stress requirements; for the stiffness adjustment, it is required that the adjustment amount gradually decays between different compensation layers, and the magnitude 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 mutate; during the damping adjustment, according to the acting direction of the adjustment force, the damping coefficient is increased to reduce the oscillation effect in the high stress gradient region.

9. The dynamic analysis system for the seismic performance and stress distribution of the multimodal ceramic material according to claim 8, characterized in that, The tracking of the stress evolution trend combines a sliding window filter and an autoregressive integrated moving average model; the sliding window filter is used to eliminate the noise in the data to avoid interference of accidental errors on the analysis results; The autoregressive integrated moving average model is used to fit the long-term stress evolution trend and predict the future stress distribution state.

10. Dynamic analysis method for seismic performance and stress distribution of multimodal ceramic materials, characterized in that, It includes: Based on the geometric configuration and loading direction of the specimen, a multi-layer non-uniform virtual compensation layer grid is generated by extending the real boundary of the specimen, and the layering density is dynamically adjusted according to the seismic spectrogram; The specimen 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 the historical stress data, and the stress evolution trend is tracked to ensure a high degree of matching between the experimental conditions and the real environment.

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