50 results about "Isogeometric analysis" patented technology

The invention provides a composite material skin isogeometric modeling method considering micro-pores, which comprises the following steps: obtaining internal characteristics of a composite material skin through an SEM scanning electron microscope, and establishing parameterized unit cell microstructure units according to the characteristics; determining a skin deformation area, constructing a constitutive matrix based on different components in the composite material, obtaining and endowing defined material attributes, and obtaining different unit mass matrixes and local stiffness matrixes in the area; and filling into the macroscopic overall matrix through an isogeometric mapping strategy, carrying out inverse mapping fitting on a skin appearance structure, and carrying out applied load calculation. According to the method provided by the invention, through an isogeometric analysis method, three-dimensional curved surface dimension reduction processing is realized, and the calculation cost is reduced; meanwhile, a parameterized microscopic unit is considered to ensure the accuracy of modeling; and the mechanical property of the composite material skin is really simulated. The method is suitable for the structure elasticoplastic deformation state that the skin bears large load, large deformation and the like, and calculation operation is easy and convenient.

An adaptive geometric modeling method for assembled thin-walled component structures oriented to integration of modeling, analysis and optimization, includes firstly, using a multi-level NURBS-based free-form deformation (MNFFD) technique to realize accurate geometric modeling of an assembled thin-walled component structure; secondly, establishing a modeling-analysis unified model suitable for isogeometric analysis of the assembled thin-walled component structure based on an MNFFD method; finally, establishing a modeling-analysis-design unified model suitable for collaborative design of a shape and a stiffened layout of the assembled thin-walled component structure based on the MNFFD method. The present invention fundamentally solves the modeling robustness problem of gaps and overlaps between thin-walled components due to the lack of accurate topological consistency in traditional modeling methods, provides a new tool for optimization design of engineering thin-walled structures. MNFFD is used, so that the geometric dimension reduction transformation from 3D design domain to 2D design domain can be realized.

The invention belongs to the field of material structure optimization, and particularly relates to an isogeometric topological optimization method based on dynamic response driving, which comprises the following steps of: (1) establishing a thin shell mid-plane geometric representation model based on a T spline and Bessel extraction technology; (2) establishing a frequency response-oriented isogeometric shell unit based on the Kirchhoff theory; (3) solving the aerodynamic response of the surface of the structure based on a high-order panel method of a T spline; (4) constructing a topology description model of the thin shell based on a Bessel unit; (5) establishing a structure dynamic flexibility minimum topological optimization model oriented to the dynamic response of the pneumatic thin shell; (6) dynamic flexibility minimization sensitivity analysis and derivation; and (7) updating optimization model design variables based on an optimal criterion method. According to the method provided by the invention, a pneumatic coupling thin shell dynamic isogeometric analysis framework is constructed, and the problems of poor geometric adaptability, difficulty in complex thin shell dynamic design, lack of pneumatic environment related to optimization and the like in an existing method are effectively solved.

The invention belongs to the technical field of road traffic noise reduction, and particularly relates to a sound barrier shape optimization method based on an isogeometric particle swarm singular boundary method. Comprising the steps of building a sound barrier geometric model, building a sound barrier shape optimization model, building a Burton Miller type singular boundary method program, calculating sound pressure, carrying out particle swarm iterative solution, outputting an optimization result and the like. According to the method, the model is optimized based on the isogeometric singular boundary method of the basic solution of the acoustic control equation for the first time, the model is applied to the optimization design of the sound barrier, the sound barrier is optimized by combining the particle swarm optimization method, only the size of the target function is needed, complex sensitivity derivation is not needed, and when the sound barrier with the complex shape is calculated, the method is simple and convenient to operate. The method has great flexibility and high efficiency, seamless integration between CAD and CAE is realized by introducing isogeometric analysis, namely representing geometric boundaries by using an NURBS function, and a tedious grid division step in an optimization process is avoided, so that the precision and efficiency of sound barrier optimization are remarkably improved.

The invention discloses an isogeometry-based composite material thin shell dynamics prediction method, and belongs to the field of composite material thin shell dynamics behavior prediction. The implementation method comprises the steps that geometric modeling is conducted on the composite thin shell based on an isogeometric analysis method, unification of geometric modeling and numerical analysis is achieved through a non-uniform B spline (NURBS), and a composite thin shell geometric model is obtained; calculating a tensile stiffness matrix, a tensile-bending coupling stiffness matrix and a bending stiffness matrix of the composite material thin shell through the composite material parameters; establishing a kinetic model of the composite material thin shell unit through continuous medium mechanics, assembling the kinetic model to obtain an overall kinetic model of the composite material thin shell, and establishing a kinetic equation of the composite material thin shell based on the overall kinetic model of the composite material thin shell and the stiffness matrix; a kinetic equation is solved based on a generalized alpha implicit time integration algorithm, the kinetic behavior of the composite thin shell under the action of an external force F is predicted, and the stability and precision of thin shell kinetic behavior prediction are improved.

The invention discloses a solver error control development method and system based on isogeometric analysis, and relates to the technical field of computational mechanics and numerical analysis, and the method comprises the steps: building an NURBS primary function according to isogeometric analysis, carrying out the grid division, generating initial grid data, calculating the stress error index of each grid unit through employing a Zienkiewicz-Zhu method, and carrying out the calculation of the stress error index of each grid unit. Grid optimization parameters are generated, local encryption processing is carried out on grid units, the order of an NURBS primary function is improved by adopting a p-refinement method, and an optimized grid structure is obtained; and inputting the optimized grid structure into a solver for iterative calculation, and when a calculation error is smaller than a preset error threshold value, outputting a solving result. According to the method, the optimal balance between the calculation precision and the resource consumption is realized through the precise geometric expression and the self-adaptive grid division of the NURBS primary function in combination with the Zienkiewicz-Zhu posterior error estimation technology.

The invention discloses a topological optimization method, device and equipment for material distribution based on particle flow, and relates to the technical field of material structure optimization. According to the method, isogeometric analysis is introduced into the material point method in topological optimization of material distribution, the isogeometric material point method is provided, consistency between geometric modeling and numerical analysis is achieved through a unified primary function of isogeometric analysis, benefit from high-order continuity of the primary function of isogeometric analysis, and the method has the advantages that the method is simple and convenient to implement. The introduction of isogeometric analysis can effectively eliminate and suppress numerical artifacts in topological optimization and unit cross instability in a traditional substance point method. According to the isogeometric material point method, movable particles of material distribution in a physical domain serve as design variables, a set of particle-grid physical information and sensitivity transmission model is established in combination with Lagrange-Euler mixed description, corresponding accurate geometric topology is output while particle evolution is achieved, and the method has the advantages of being high in accuracy and high in reliability. And the accuracy and the flexibility of topological optimization of the material distribution structure are remarkably improved.

The invention relates to the technical field of medical image processing, and discloses a temporomandibular joint three-dimensional reconstruction system based on joint imaging diagnosis. The system utilizes CBCT equipment to collect temporal-mandibular joint tomographic image data, and extracts facial feature sites and maxillofacial joint standard model approval sites through a multi-scale residual network. And carrying out space registration by adopting an affine transformation and nonlinear optimization algorithm to generate a synchronous correction parameter, further carrying out deformation interpolation on the standard model of the maxillofacial joint to construct a maxillofacial model, and adjusting the position of a condylar process. And based on the deformed maxillofacial model, generating an occlusal plate structure model by using an isogeometric analysis method, and iteratively optimizing the degree of fit through an edge calculation frame. The system can accurately reconstruct the three-dimensional model of the temporomandibular joint, optimizes the adaptation of the biteplate, provides powerful support for the diagnosis and treatment of temporomandibular joint diseases, and facilitates the improvement of the diagnosis and treatment level.

The invention discloses a motorized spindle thermal characteristic analysis modeling method based on multi-patch isogeometric analysis, which comprises the following steps: S10, carrying out geometric modeling of a high-speed motorized spindle: constructing a multi-patch solid model comprising a motorized spindle stator, a rotor, a bearing and a cooling pipeline of the high-speed motorized spindle by adopting a three-dimensional NURBS patch splicing technology, geometric continuity and parameterization consistency are ensured; s20, performing heat conduction analysis: constructing a transient heat conduction control equation based on a Fourier heat conduction differential equation in combination with high-order smoothness characteristics of the IGA, and solving a temperature evolution process in a time domain through a backward difference method; and S30, performing thermal error modeling: introducing an elastic mechanical constitutive relation and a fixed support boundary, and establishing a thermal-force coupling solving framework.

The application discloses a structure nonlinear deformation reconstruction method and system based on isogeometric and reduced basis, and the method comprises the following steps: measuring initial strain data of a ship plate structure surface, constructing a plurality of four-node inverse shell elements of the ship plate based on the initial strain data; assembling the plurality of four-node inverse shell elements to obtain a whole stiffness matrix; reconstructing the whole stiffness matrix based on the measured strain data of the ship plate to obtain a linear reconstruction result of the ship plate; correcting the linear reconstruction result based on the reduced basis, and fusing the correction increment to the linear reconstruction result for nonlinear iteration to complete nonlinear deformation reconstruction. On the basis of the principle of isogeometric analysis, the application combines the inverse finite element method to establish a four-node inverse shell element, realizes high-precision ship structure displacement reconstruction through a small number of strain measuring points, and helps designers to intuitively understand and deeply understand the mechanical properties of the structure and to monitor the safety of the structure in real time.

The invention belongs to the technical field related to robot machining, and discloses an optimal design method and equipment for a three-dimensional complete continuous functional gradient lattice extension rod, and the method comprises the steps: constructing a mapping relation between geometric and physical properties of a lattice structure; by combining the continuous, smooth and locally controllable characteristics of the NURBS body, the completely continuous characterization and regulation of the property distribution of the functionally gradient lattice structure are carried out, the completely continuous smooth transition of the lattice structure in a three-dimensional space is realized, and compared with an incomplete continuous functionally gradient lattice structure, the preparation method has the advantages that the preparation cost is reduced; the completely continuous functional gradient lattice structure has higher structural strength and optimization potential; a high-order shear beam theory and an isogeometric analysis method are combined to construct a dynamic model of a three-dimensional complete continuous functional gradient lattice structure, and a theoretical basis is provided for subsequent robot system dynamic modeling of an additional lattice extension rod; on the basis of the method, distribution characterization-regulation and control design-performance analysis of the three-dimensional completely continuous functional gradient lattice structure can be realized.

The invention discloses a B-spline finite element analysis topological optimization method based on a neural network, which fuses a non-uniform rational B-spline (NURBS) and a physical information neural network (PINNs), and comprises the following steps of: performing geometric region and structural density representation by using the NURBS, inputting a control point of a geometric region into an isogeometric neural network based on the PINN, and outputting a density control point; then, isogeometric analysis is used for displacement calculation, and a structural performance index is calculated as loss. And finally, performing sensitivity analysis by using a built-in back propagation mechanism so as to optimize density field distribution. The optimized density field is obtained through continuous forward propagation, performance index (such as flexibility) calculation, back propagation and weight updating until a preset convergence condition or the maximum number of iterations is reached. According to the method, the modeling capability of the neural network and the accuracy of finite element analysis based on the B-spline can be effectively combined, and efficient and accurate topological optimization is realized.

An adaptive geometric modeling method for combined thin-walled component structures with integrated modeling-analysis-optimization. First, the free deformation technology MNFFD based on multi-level NURBS is used to realize accurate geometric modeling for combined thin-walled component structures. Secondly, a unified modeling-analysis model suitable for geometric analysis of combined thin-walled component structures is established based on the MNFFD method. Finally, a unified modeling-analysis-design model suitable for the collaborative design of the structural shape and reinforcement layout of combined thin-walled components is established based on the MNFFD method. The present invention fundamentally solves the modeling robustness problem of gaps and overlaps between thin-walled components caused by the lack of precise topological consistency in traditional modeling methods, provides a new tool for the optimal design of engineering thin-walled structures, can greatly improve product design accuracy and shorten the development cycle; the use of MNFFD can realize the geometric dimensionality reduction conversion from three-dimensional design domain to two-dimensional design domain, and breaks through the problem of adaptive updating of design models, and realizes the decoupling of design domains of combined thin-walled component structures with complex assembly relationships.

The invention is suitable for the technical field of heat conduction analysis, and relates to an underground granary heat insulation performance simulation method based on axisymmetric geometric analysis, which utilizes a non-uniform rational B-spline (NURBS) primary function to accurately represent a geometric shape and approximate a physical field, realizes the unification of modeling and analysis data, and improves the heat insulation performance of an underground granary. The axisymmetric characteristics and boundary conditions of the granary are fully utilized, geometric analysis system equations and solving formats such as the axisymmetric heat conduction problem are deduced in a cylindrical coordinate system from an axisymmetric steady-state heat conduction problem control equation on the basis of the variational principle, and a general three-dimensional problem is reduced into a two-dimensional problem; efficient utilization of the degree of freedom of calculation is achieved, then temperature field and heat flux density distribution characteristics of a granary body-soil body system are analyzed, the influence rule of different conditions on underground granary heat conduction is revealed through parameterization research, and a high-order continuous interpolation basis function is introduced to obtain a high-order continuous interpolation basis function; the calculation precision and calculation efficiency of underground granary temperature field analysis are effectively improved.

The invention discloses a method for generating a quadrilateral curved surface grid, the quadrilateral curved surface grid can cover the curved surface of a three-dimensional object so as to analyze the three-dimensional object, and the method comprises the following steps: obtaining a curved surface digital geometric model of the three-dimensional object; constraint on grid singular point configuration on the curved surface is received, the singular point configuration comprises at least one designated position and a target price number of the designated position, and the price number represents the number of edges connected with grid vertexes; on the basis of the Riemannian-Rooch theory, a finite-dimensional quadrilateral grid generation space is constructed within the range meeting singular point configuration constraints, and construction comprises calculation of a primary function of a sub-pure function linear space L (D) corresponding to singular point configuration; selecting a specific grid generation parameter combination from the quadrilateral grid generation space; a quadrilateral curved surface grid is generated and output according to the grid generation parameter combination, and singular point distribution of the grid conforms to the received constraint; and the quadrilateral curved surface grid is provided for a finite element analysis or isogeometric analysis solver and is used for carrying out simulation analysis of mechanics, thermotics or fluid dynamics on a three-dimensional object.

The invention provides an isogeometric analysis control grid-oriented graph neural network Poisson equation solving method. The method comprises the following steps of S1, matching data set acquisition and input formats; s2, carrying out proportion division on the data set; s3, constructing a graph neural network model; s4, performing model training and parameter initialization; training a model by using a training set, and monitoring a training effect through a verification set by taking Poisson solution error minimization and operation speed maximization as targets; step S5, Poisson solution and performance verification: executing Poisson solution by using the test set, calculating a solution error and a running speed which need to be superior to a file specified standard, and returning to adjust model parameters and retraining if the standard is not reached; and S6, outputting a result. Step S7, Main file integration and interface implementation: writing Main file integration functions from the step S1 to the step S7; according to the method, the problem that the compatibility of a data set and input of an existing method is limited remarkably in the engineering simulation and scientific calculation process can be solved.

This invention discloses a structural thermo-mechanical coupling method and apparatus considering isogeometric analysis, belonging to the field of thermodynamics. The method includes: S1. Establishing an isogeometric NURBS model: providing the basis for expressing geometric and physical fields for thermo-mechanical coupling analysis, achieving seamless integration of CAD and CAE; S2. Calculating the transient temperature field based on the central difference method: obtaining the temperature distribution of the structure at different times, providing temperature input for subsequent thermo-mechanical coupling; S3. Transforming the temperature field into equivalent temperature loads: converting the thermal effects caused by temperature changes into equivalent loads identifiable by structural mechanics analysis; S4. Solving the stiffness equation of the structure under the combined action of external forces and temperature: obtaining the displacement matrix of the structural control points; S5. Solving the structural coupling field based on the displacement matrix: obtaining all key physical quantities in the thermo-mechanical coupling field, completing the coupling analysis. This invention can verify the feasibility of applying isogeometric analysis in coupled fields.

The application relates to the field of artificial intelligence, and particularly discloses an industrial design parameterized design system with multidimensional simulation feedback, which comprises a parameterized modeling module, a multidimensional simulation module, a simulation agent model construction module, a multidimensional feedback fusion and optimization module, an iterative convergence discrimination module and an interactive visual feedback module; the parameterized modeling module is used for generating an integrated parameterized three-dimensional model containing geometric features, material distribution and topological structure according to input design parameters. The application constructs an integrated parameterized three-dimensional model fusing geometric features, material distribution and topological structure, realizes millisecond-level real-time updating of the model through an incremental constraint solver, adopts an isogeometric analysis method based on NURBS, unifies the discretization process of modeling and simulation, avoids model conversion errors and realizes seamless connection of parameterized modeling and multi-physical field simulation.

The invention discloses an assembly joint surface contact deformation prediction method based on an enhanced depth operator network. Comprising the following steps: firstly, establishing an isogeometric analysis model of an assembly joint surface, and constructing a joint surface deformation data set by changing the rough morphology of the joint surface of the isogeometric analysis model and changing different loading forces; then, constructing an enhanced depth operator network, and training the enhanced depth operator network by using the joint surface deformation data set to obtain an assembly joint surface contact deformation prediction model; and finally, inputting the rough morphology and the loading force of the to-be-measured assembly joint surface into the assembly joint surface contact deformation prediction model, and outputting an assembly joint surface contact deformation result by the model. According to the method, the image generator is used as a backbone network of the depth operator network, so that the prediction precision of the depth operator network on the contact deformation of the assembly joint surface is enhanced. The method can be used as a rapid evaluation tool for the product part assembly joint surface rough morphology optimization design effect.

The present invention discloses a three-dimensional CAD reconstruction method for pixel-based topology optimization results, comprising the following steps: S1, performing a smoothing operation on the discrete voxel model generated from the topology optimization result; S2, extracting the triangular mesh on the surface of the smoothed discrete voxel model to generate a skeleton line of the triangular mesh model; S3, simplifying the skeleton information of the triangular mesh model; S4, generating a coarse skeleton model; S5, performing a Catmull-Clark volume subdivision operation on the coarse skeleton model and projecting the surface vertices onto the surface triangular mesh generated in step S2 to generate a Bézier volume model, which can conveniently and efficiently convert the discrete hexahedral mesh model generated by topology optimization into a Bézier volume model. It has a significant advantage in the number of generated Bézier volume models, and at the same time eliminates the jagged structure of the discrete hexahedral mesh model, having application value in the field of topology optimization. The model reconstructed by CAD can also be applied to isogeometric analysis and has application value in the field of isogeometric analysis.

The application discloses an isogeometric analysis simulation method of a hyperelastic material model based on body subdivision. The isogeometric analysis adopts the division of a spline model parameter domain and the mapping of the parameter domain to a physical model, avoids the time consumption of mesh division in a finite element, and realizes an integrated process from modeling to simulation in combination with a CC subdivision method. The application comprises the following steps: converting a CC subdivision body into a spline body model, and establishing a mapping relationship of control points of the subdivision body and the spline body; establishing a hyperelastic material constitutive model according to geometric boundary conditions and material parameters; establishing a discrete balance equation of the model according to an isogeometric method; in combination with the balance equation, establishing a model motion equation and a nonlinear solving system; using a Newton iteration method to solve the nonlinear system, obtaining displacement solutions at each time step, and mapping the displacement solutions back to the subdivision body, so as to realize deformation simulation of the subdivision body.

The embodiment of the application provides a kind of entity unit isogonic analysis method, device, equipment and storage medium for variable-thickness composite material, the method comprises: based on entity geometry model, construct the entity grid model of NURBS, and extract the parameterization information of NURBS;Local coordinate system is established in each gauss point inside geometry entity using parameterization information, determine the first conversion relationship of local coordinate system and global physical coordinate system;Based on entity grid model, construct nonlinear function in parameter space, use L-M algorithm to iteratively solve the intersection of each ply offset surface and thickness direction parameter curve of variable-thickness composite material, determine the integral interval inside each entity unit;Based on geometric volume integral term and the ply trigonometric function of variable-thickness composite material, determine global stiffness matrix;Based on global stiffness matrix, execute isogeometric analysis to determine the laminated structure strain energy, vibration frequency and buckling factor of composite material by loading and defining boundary conditions.

The invention relates to a multi-piece multi-dimensional functionally graded material optimization method, device, equipment and medium, and belongs to the technical field of functionally graded materials.According to the multi-piece multi-dimensional functionally graded material optimization method, a multi-piece three-dimensional functionally graded material porous structure is constructed based on a B spline or NURBS; the constructed PHT-AIGA is adopted to carry out self-adaptive solution and iterative refinement on the geometric configuration of the porous structure of the multiple pieces of three-dimensional functionally graded materials, a numerical analysis template grid meeting an error threshold value is obtained, and the PHT-AIGA comprises geometric analysis such as a PHT spline base, a super-convergence recovery base error estimation algorithm and a Doffler marking strategy; according to the method, a multi-objective optimization function is constructed with the minimum mass and the maximum free vibration fundamental frequency as optimization objectives, iterative solution is conducted on the multi-objective optimization function, optimized design variables are obtained, and the precision and efficiency of multi-objective optimization of the multiple pieces of three-dimensional functionally graded materials are improved.

This adaptive geometric modeling method for combined thin-walled component structures is focused on integrating modeling, analysis, and optimization. First, a multi-level NURBS-based free deformation (MNFFD) technology is used to achieve accurate geometric modeling for combined thin-walled component structures. Second, a unified modeling and analysis model suitable for isogeometric analysis of combined thin-walled component structures is established based on the MNFFD method. Finally, a unified modeling, analysis, and design model suitable for the joint design of the shape and reinforcement arrangement of combined thin-walled component structures is established based on the MNFFD method.The invention fundamentally solves the modeling robustness problem of gaps and overlaps between thin-walled components caused by the lack of precise topological consistency in conventional modeling methods, and provides a new tool for the optimized design of engineering thin-walled structures, which can significantly improve the accuracy of product design and shorten the development cycle; the use of MNFFD can realize the conversion of geometric dimensionality reduction from the three-dimensional design domain to the two-dimensional design domain, solve the problem of adaptive update of the design model, and realize the decoupling of the design domain from the combined thin-walled component structures with complex assembly relationships.

This application discloses an isogeometric transient temperature field analysis method integrating birth and death element technology, relating to the field of computational mechanics. The method includes establishing an isogeometric NURBS model, calculating the element heat transfer matrix, element thermal melting matrix, and element load array; determining whether the current calculation element is in the computation time domain; if not, setting the element heat transfer matrix and element load array to 0; if so, restoring the loads corresponding to the element heat transfer matrix and element load array, and removing the loads shared by the element and other elements in the computation time domain at their boundary; assembling the element heat transfer matrix, element thermal melting matrix, and element load array into a global matrix, and constructing the heat transfer equation based on the global matrix; calculating the temperature of the control points based on the heat transfer equation, and determining the temperature field of the final solution domain. This application considers the realization of an isogeometric transient temperature field analysis method under complex temperature load conditions including time-series problems, promoting the application of isogeometric analysis in engineering.

The application provides a viscoelastic isometric topology optimization method under transient load based on BESO, and belongs to the technical field of isometric topology optimization, and comprises the following steps: isometrically gridding a to-be-designed model to obtain the coordinates of control points and Gauss points corresponding to each unit; long-term global stiffness matrix and global mass matrix are constructed; the target volume of optimization is determined; on the basis of the long-term global stiffness matrix, tangent stiffness matrix and historical stiffness matrix are obtained, and viscoelastic isometric analysis is carried out. According to the definition of the optimization problem, the target value of the structure is calculated, and the sensitivity of the target function with respect to the design variable is calculated by using the adjoint method; after the sensitivity value of each unit is filtered through a distance filter, the sensitivity at the control points is extended through a NURBS filter, and a global sensitivity field is established; and the design variable is updated according to the set evolution ratio parameter. The application can accurately simulate the response of the structure under complex dynamic loading.

The invention discloses a multi-patch structure adaptive isogeometric topology optimization method and system based on a truncation level B spline, and relates to the technical field of CAD / CAE integrated design. According to the method, multi-patch model data is analyzed, and a truncation level B spline space and a multi-patch level isogeometric analysis grid are initialized; constructing a self-adaptive multi-patch isogeometric analysis grid based on a residual posterior error estimator to solve a structural displacement field; meanwhile, a uniform and fine multi-patch isogeometric design grid is constructed, a multi-patch tensor integral solution implicit filter and control point index transformation are utilized to achieve efficient obtaining of sensitivity of an objective function and a volume constraint function on multi-patch control point variables, and an OC optimization criterion is adopted to iteratively update control point optimization variables; in the iteration process, a density change indicator and a posterior error indicator are combined for self-adaptive subdivision and reinitialization, and efficient and high-precision optimization solution under the decoupling condition of the analysis grid and the design grid is achieved.

The present invention relates to a rapid simulation method for fluid-solid coupling of heart valves based on isogeometric analysis, comprising step 1: optimizing fluid subproblems: simplifying the background grid of the fluid subproblems, generating Bézier tetrahedron background grids based on the simplified grids, and solving the fluid subproblems using the geometrically irrelevant field approximation idea; step 2: optimizing solid subproblems: using a strategy to divide the NURBS surface used in the solid subproblem into sliced ​​NURBS surfaces; step 3: using an augmented dynamic Lagrange multiplier method to couple the fluid-solid subproblems; step 4: solving the fluid-solid coupling problem and analyzing the results, and using the method proposed in this article to optimize the problem during the computer simulation of the heart valve, the efficiency of the simulation program can be improved while ensuring a certain accuracy. Compared with relevant research in recent years, the heart valve optimization simulation algorithm in the present invention is about 49% faster.

The application discloses an equal geometry-based multi-scale topological optimization method for anisotropic periodic structure material, and comprises the following steps: (1) modeling according to an equal geometry analysis method to obtain discrete point information of a macro periodic structure and various microstructure design domains, and dividing a design subdomain for the macro periodic structure design domain; (2) constructing a coordinate conversion relationship between a natural coordinate system and a material coordinate system in an anisotropic material; (3) performing periodic material distribution optimization to determine the position of various microstructures in the macro periodic structure and the volume fraction of various microstructures by normalizing the relative density; and (4) performing periodic structure / material multi-scale parallel topological optimization to determine the macro periodic structure, various microstructures and equivalent elastic matrices thereof. The application performs multi-scale topological optimization for an anisotropic periodic structure / material based on equal geometry analysis, and is accurate, stable and efficient in convergence, and can improve the structure performance from the macro and micro scales and the structure and material angles.

The application discloses a gradient progressive fusion unstructured isometric representation and analysis method, and relates to the technical field of computational mechanics and engineering numerical simulation. The method comprises the following steps: firstly, acquiring geometric information of a T-spline surface calculation domain, and constructing an isometric analysis graph neural network model; then, selecting matching points in a corresponding parameter domain, and assembling an interpolation parameter matrix and a partial derivative parameter matrix; subsequently, adopting a gradient progressive fusion model training strategy, determining a model loss value obtained by weighted summation of a gradient loss term, a control equation residual loss term and a boundary condition loss term based on the parameter matrix, training the model, converting partial differential equation solving into a neural network parameter optimization problem, and simultaneously fusing multi-stage gradient information to improve training stability and calculation precision; and finally, predicting control vertex physical parameters by using the trained model, and obtaining physical parameter distribution in the calculation domain through spline interpolation. The application realizes fast and accurate solving of partial differential equations in a complex geometric domain.