66 results about "Finite element mesh generation" patented technology

The invention discloses an analysis method of motor crank dynamics, which includes that: in Hypermesh software, a crank system is divided by finite element mesh generation into a crank, a flywheel, a belt pulley, a timing gear and a main bearing seat etc.; use Nastran software to execute the reduction solving of a finite element substructure; in EXCITE software, construct a model of the crank system dynamics, and exert the corresponding boundary condition on elements to implement simulation calculation; use the Nastran software to implement restoration solving of dynamic stress on the crank, perform post-processing and execute fatigue analysis on dangerous points; reasonably evaluate the crank system according to the results, and if the structure is not reasonable, the structure optimization is still needed. The method uses EXCITE calculation technique to execute dynamics analysis on the motor crank, obtains the strength and the fatigue parameters of the motor crank, and further evaluates the structure parameters of the crank and the related parts of the motor reasonably, therefore, making the improvement thereof.

A computing method for hub ultimate strength of a wind turbine generator system belongs to the technical field of wind power generation, and comprises the following steps: modeling by adopting software of finite element analysis, performing finite element mesh generation, setting constraint conditions and computing to obtain a deformation and stress cloud chart. The modeling process is as follows: 1, drawing a 3D model for a hub, importing the 3D model into a finite element software platform, and drawing a 3D entity model for the connection part of blades and the hub and the connection part of a main shaft and the hub in the finite element software; 2, setting material attributes for the blades, the main shaft and the hub, establishing a finite element model thereof, rigidly coupling the blades, the main shaft and the hub, and determining an overall coordinate system of the hub; 3, establishing nodes at root parts of the hub and each blade, converting the nodes into a blade root coordinate system specified by Germanischer Lloyd, then rigidly coupling the nodes to the blades, so that the load can be transmitted to the hub through the blades. The computing method facilitates accurate computation of strength performance of the hub, saves the computing time and improves the computing efficiency.

The invention relates to a pipeline valve safety assessment method based on limit external load calculation. The method comprises steps as follows: S1, establishing a three-dimensional geometrical model of a valve, a pipeline and a connecting piece; S2, performing finite element mesh generation on the three-dimensional geometrical model to establish a finite element mesh model; S3, establishing a limit external load finite element calculation model on the finite element mesh model; S4, performing calculation according to the limit external load finite element calculation model to obtain a limit external load; S5, establishing multiple combined external load finite element calculation models under the combined action of the limit external load and the maximum working pressure on the finite element mesh model; S6, calculating the stress distribution of the pipeline valve through the combined external load finite element calculation models and determining the safety performance of the pipeline valve according to the stress distribution. With the adoption of the method, the effect caused by the external load on the pipeline valve can be considered before prototype production, whether the strength property of the valve meets the design requirement or not can be judged, potential risks can be predicted, and the product development cycle is shortened.

The invention discloses a generating method of a finite element mesh in a thin-wall curved surface structure, aiming to solve the technical problem of great equivalent stress of a traditional design method of a finite element model in a perforated thin-wall conical curved surface structure. The technical scheme comprises the following steps of: firstly, generating a plane finite element mesh on a parameter plane by adopting a solid modeling method; then, generating network nodes in a space thin-wall curved surface structure through a parametric mapping relation by adopting a direct generating method; and generating a finite element mesh in the space thin-wall curved surface structure by utilizing corresponding unit topology information on the parameter plane. Compared with the prior art, the maximum equivalent stress of the finite element model in the perforated thin-wall conical curved surface structure in the same size is greatly reduced.

The invention discloses a modeling method for MJ bolt and nut finite element meshes. The method comprises the following specific steps: I, summarizing geometrical features of a bolt and a nut; II, performing mathematical description on a thread zero-position section of the bolt; III, performing mathematical description on a thread zero-position section of the nut; IV, generating unthreaded region finite element meshes of the bolt and the nut; and V, generating thread node offsets of the bolt and the nut, and performing node movement on meshes on threads in order to obtain a threaded bolt. Through adoption of the modeling method, the MJ bolt and nut finite element meshes with threaded structure features can be generated rapidly and effectively. The meshes are hexahedron co-node meshes, so that errors caused by adoption of a TIE command or a tetrahedron mesh can be effectively avoided, and the calculation accuracy is increased greatly.

The invention discloses a method and apparatus for analyzing a welded structure. The method comprises the steps of: obtaining a three-dimensional model of the welded structure; acquiring a welding joint standard model corresponding to each weld on a three-dimensional model of the welding structure, wherein the welding joint standard model is preset; performing finite element mesh generation on thethree-dimensional model of the welded structure; loading welding result data of each of the welding joint models from a welding structure calculation database, and performing strength and fatigue analysis on the three-dimensional model of the welding structure according to the welding result data of each of the welding joint models, wherein the welding structure calculation database is established in advance; if it is judged that the result of the strength and fatigue analysis meets the design requirement, outputting the message that the welded structure is qualified. The apparatus is used toperform the method described above. The analysis method and the device of the welding structure provided by the invention improve the reliability of the welding structure.

The invention belongs to the field of structural optimization design, and particularly discloses a topological optimization method for a multi-material structure. The method comprises the steps of performing finite element mesh generation on a design domain of a to-be-processed object to obtain a preset number of mesh units, and establishing level set functions in one-to-one correspondence with entity materials; calculating an elastic matrix, a rigidity matrix and a displacement vector; calculating a velocity field and a sensitivity degree, and converting or deleting the entity material in thegrid cell according to the sensitivity degree to obtain a level set function after the first optimization under the current iteration; updating to obtain a level set function optimized for the secondtime under the current iteration by utilizing the speed field; and judging whether the result of the second optimization is converged or not according to the flexibility and the volume error. According to the method, the defects that a classical level set topological optimization method depends on initial design and a two-way progressive optimization method cannot obtain a smooth boundary are overcome, the structural rigidity is improved to a certain extent, and the provided method is stable and effective.

The invention provides a node information optimization processing method and a device based on a CAE model, comprising the following steps: acquiring a body-in-white, wherein the body-in-white comprises node information and grid information at a hole; The CAE model of body-in-white (BIW) computer aided engineering (CAE) is constructed by the finite element mesh generation of BIW with Hypermesh software. The node information is stored in the csv table, and the optimization processing device is called in the CAE model of the body-in-white, the node information in the csv table is in the coordinate position, and the node is constructed in the form of the temporary node; the node information is stored in the csv table, and the optimization processing device is called in the body-in-white CAE model. Based on the mesh information at the temporary nodes and holes, Load points for the same model, Unify the positions of output points and connection points to avoid the difference of analysis results caused by the difference of positions and the situation that no leakage point will appear. The loading points, output points and connection points of the same model can be unified to avoid the difference of analysis results caused by the difference of positions and the situation that no leakage point will appear.

The invention discloses a method for obtaining the quenching process heat transfer coefficient of an aluminum alloy component under the three-dimensional heat transfer condition based on a finite element method, and relates to the technology of obtaining the heat transfer coefficient under the three-dimensional heat transfer condition. The method aims to solve the problem that the heat transfer coefficient obtained under the one-dimensional heat transfer condition does not agree with the heat transfer coefficient of the actual aluminum alloy component under the three-dimensional heat transfer condition, and thus the obtained heat transfer coefficient is inaccurate. The method includes the steps that a three-dimensional heat conduction differential equation under a rectangular coordinate system is established; on the basis of the finite element computing method, the aluminum alloy component is subjected to finite element mesh generation, and the temperature field corresponding to a certain moment of time is calculated; whether the test temperature and the calculating temperature of a test point meet a convergence condition or not is judged; if yes, the method is ended; if not, a novel heat transfer coefficient is obtained through optimization by means of a genetic algorithm; a novel temperature field is calculated according to the novel heat exchange coefficient, and whether the test temperatures and the calculating temperatures of N test points meet the convergence condition or not is continuously judged. The method can be used for obtaining the heat transfer coefficient under the three-dimensional heat transfer condition.

The invention discloses an internal fixed parameter optimization treatment individualized modeling method based on a fracture healing process. The method comprises the following steps that a fracturesite is scanned, modeling is performed on a fractured bone; an orthogonal experimental design method is adopted to combine and assemble different internal fixed parameters in a three-dimensional software, the finite element mesh generation is performed on a fractured bone model, a mechanical property value is assigned according to a gray value on the fractured bone of an internal fixation system;the assembly of different screws is carried out, and whole finite element mesh generation is carried out; a mechanical environment simulating the fractured bone is loaded and calculated, a stress on the internal fixation system and a healing result of the fracture are obtained, and then the fracture healing result is evaluated; the screw layout is updated, and the above steps are repeated to perform combined optimization on the screw layout The internal fixed parameter optimization treatment individualized modeling method based on the fracture healing process has the advantages that the errorcaused by manually dividing the cancellous bone and the bone cortex is avoided, and a basis is provided for the combined optimization selection of the internal fixed parameters of a bone fracture plate during the fracture treatment.

The invention relates to a method for constructing a three-dimension finite element model which treats a tibial plateau posterior-lateral fracture with different inner fixing manners. The method specially includes the following steps that CT tomography is used for obtaining cross-sectional image data of a normal tibia attached outer steel plate and a normal tibia attached rear steel plate; application open source software ITK-SNAP is used for carrying out medical image processing and cutting; a solid geometric model is generated in professional three-dimension finite-element mesh generating software HyperMesh; solid geometric models in different assemblies are selected according to needs in the HyperMEsh and assembled, a needed model containing the whole tibia, a tibial fracture model and a model for treating the tibial fracture with different inner fixing manners are generated, each model is composed of multiple assemblies, each assembly is divided into grids respectively and multiple tetrahedron finite element models which treat the tibial fracture with different inner fixing manners and of the tibia are finally generated. According to the method for constructing the three-dimension finite element model which treats the tibial plateau posterior-lateral fracture with different inner fixing manners, the ITK-SNAP and the HyperMesh software are used for rapidly and accurately setting up the three-dimension finite element model which treats the tibial plateau posterior-lateral fracture with different inner fixing manners, the modeling speed and the modeling quality are greatly improved and a base is laid for further biomechanical analysis.

The invention discloses a PMFCL (permanent-magnet-biased fault current limiter) magnetic current thermal coupling modeling method. The PMFCL magnetic current thermal coupling modeling method includes establishing a 2D model of a half-wave current-limiting topological structure of the PMFCL; employing finite element software Ansoft to simulate the model; establishing a 3D model of the half-wave current-limiting topological structure of the PMFCL by the aid of the Ansoft; establishing a transient thermal analysis model in the ANSYS, subjecting the transient thermal analysis model to finite element mesh generation and subjecting a temperature field to graph mapping to the 3D model of the half-wave current-limiting topological structure of the PMFCL, and accordingly obtaining a temperature field calculation result of a PMFCL device at any moments. According to the arrangement, electromagnetic fields and current vectors of a winding and components of a linear PMFCL are analyzed and calculated with thermal fields to obtain magnetic-current-thermal coupling analysis, accordingly imparting a significant reference for material types and parameter designs of the PMFCL.

The invention discloses a side slope three-dimensional finite element mesh generation method under a complex geological condition. The method comprises the following steps that: 1) on the basis of a CAD (Computer-Aided Design) platform, extracting topographic contour and geological interface elevation point data; 2) establishing the mesh node data of target range plane projection; 3) on the basisof an inverse distance interpolation method, constructing three-dimensional mesh node data in the target range; 4) creating the mesh node and the unit of a specified node sequence to obtain a three-dimensional finite element mesh; and 5) checking the quality of the generated finite element mesh, and if the quality is not qualified, returning the step 3) to regenerate the finite element mesh. The method provides a feasible finite element mesh division thought, the three-dimensional finite element calculation mesh under the complex geological condition can be established at high efficiency and high accuracy, the quality and the amount of the finite element mesh can be effectively controlled, repeatability is high, simplified processing is not required, and a finite element calculation effectis good.

The invention discloses a CFD-FEM-SPH four-way coupled liquid-carrying ship water elastic response simulation method, which comprises the following steps: S1, establishing a three-dimensional finite element model of a ship body structure in an FEM solver, performing finite element mesh generation on the ship body structure, defining parameters of various structural units, and applying constraints and loads; s2, establishing a numerical pool model in the CFD solver, establishing a pool fluid domain and a hull shell model, and setting various conditions; s3, establishing a liquid tank sloshing model in the SPH solver, and performing attribute setting on the liquid tank; s4, setting a CFD-FEM-SPH four-way fluid-structure interaction data transmission method; and S5, performing program operation solution and data export. According to the method, the combined action of ship motion, wave load, liquid tank sloshing and structural response is comprehensively considered, various fluid-solid coupling problems are fully considered, and the motion and stress conditions of the liquid-carrying ship sailing in waves can be more accurately simulated.

The invention belongs to the technical field of strength analysis and simulation, and particularly relates to a shaft part strength finite element analysis method. The analysis method comprises the following steps: establishing a shaft part mathematical model by utilizing three-dimensional modeling software, and storing or exporting the model in a file format which can be identified by the analysis software; simplifying the model, and cancelling unnecessary geometrical characteristics; entering finite element analysis software, and setting a resolving type; importing the part mathematical model into finite element analysis software; selecting a tetrahedron or hexahedron unit to perform finite element mesh generation on the mathematical model; adding materials to the mathematical model or unit and inputting material parameters; applying boundary conditions to the mathematical model, the finite element or the node; setting a resolving output item; and resolving and displaying a resolvingresult. The phenomenon that the analysis result does not accord with the actual situation due to incorrect constraint modes, torque and bending moment applying modes and positions of the bearing, thekey groove, the spline and the gear is effectively avoided. The analysis result obtained by adopting the analysis method provided by the invention is more accurate.

The invention relates to a parametric modeling method of a laminated composite plate imitating mother-of-pearl, which comprises the following steps: setting geometrical structure parameters of the mother-of-pearl layered composite plate; according to the geometrical structure parameters, establishing a three-dimensional geometrical model of laminated composite plate imitating mother-of-pearl; obtaining a finite element mesh model of the laminated composite plate imitating mother-of-pearl through the mesh parameters by conducting finite element mesh generation on the plate. The script file is compiled by Python language, an internal function of ABAQUS is called to complete modeling operation, the script file runs in ABAQUS software, and thus automatic and parameterized modeling of laminatedcomposite plate imitating mother-of-pearl are realized. The invention only needs to modify the geometrical structure parameters and mesh partition parameters of the pearl mother-of-pearl layered composite plate in the script file according to the actual requirements, and through running of the script file again, the geometric model and finite element mesh model of laminated composite plates withdifferent geometrical parameters and element densities can be generated automatically. The modeling process is highly automated and efficient, which can greatly reduce the modeling work in the simulation analysis and optimization design of mechanical properties of laminated composite plates imitating mother-of-pearl.

The invention discloses a wind power tower cylinder oil seal platform welding residual stress prediction method and a welding process optimization method. The method comprises the steps of obtaining structural parameters, welding material parameters, welding modes and heat source parameters of a wind power tower cylinder; establishing a three-dimensional model of the wind power tower drum containing the weld joint according to the structural parameters of the wind power tower drum; determining a heat source model according to the welding mode; carrying out finite element mesh generation on thethree-dimensional model of the wind power tower drum; performing welding simulation based on the wind power tower three-dimensional model, the heat source model, the heat source parameters and the welding material parameters obtained after finite element mesh division, performing finite element analysis on a temperature field and a stress field in the welding process, obtaining a residual stressprediction result of the wind power tower after welding, providing a reference basis for optimization of welding process parameters, and therefore, the welding process can be adjusted and optimized, an excellent welding seam is obtained, and the service life of the wind power tower is prolonged.

The invention provides a rock mesoscopic numerical model generation method and system capable of avoiding a malformation calculation unit, and the method comprises the steps: 1, obtaining the microscopic image features of a rock sample through numerical image processing, carrying out random point scattering based on a point saturation theory in a spatial domain, extracting the spatial position ofmineral particles, carrying out Voronoi diagram-based spatial region division on the particle aggregate in the boundary of the rock sample to generate a Voronoi polygon, and simulating a mesoscopic geometric structure of irregular shapes of mineral particles; 2, calculating a centroid coordinate of the polygon according to geometric information of the polygon, and carrying out spatial subdivisionagain by adopting a centroid iteration method until a set iteration stop standard is met; replacing all short edges of the mineral particles with short edge midpoints, and regenerating a rock mineralparticle model; and 3, performing finite element mesh generation on the model, and inserting thickness-free interface units into particle boundaries and the interior of the particle boundaries to generate a finite element numerical model capable of simulating rock cracking.

The invention discloses an equivalent stiffness-based dynamic SSS clutch modeling method. The method comprises the following steps of: carrying out three-dimensional modeling and finite element mesh generation on an SSS clutch so as to obtain a finite element model of the SSS clutch, applying a boundary condition on the finite element model of the SSS clutch to calculate lateral displacement of each position point on an axis position of the SSS clutch, and drawing a deflection curve; and keeping the main three-dimensional model of the SSS clutch unchanged, removing engaging teeth of an intermediate shaft and an output shaft, selecting corresponding nodes on the outer side surface of the intermediate shaft and the inner side surface of the output shaft to establish a matrix unit, setting a same boundary condition to carry out finite element calculation, optimizing stiffness elements in the matrix unit by adoption of an optimization algorithm until a deflection curve fitting degree achieves a convergence standard, and outputting each element of the matrix unit. According to the method, a dynamic model of the SSS clutch is established: gear teeth are removed on the basis of keeping the main body of the SSS clutch unchanged, so as to connect the intermediate shaft and the output shaft via the optimized matrix unit and then replace gear teeth engaging contact.

The invention discloses a dynamics optimization simulation analysis method for a driving mechanism of a rail-mounted inspection robot. The method comprises the following steps: acquiring material attributes and sizes of components of the driving mechanism of the rail-mounted inspection robot; establishing a three-dimensional model by utilizing a finite element method parameterization technology and carrying out parameterization processing on the main structure size; applying material attributes and establishing a standby material library; applying boundary conditions and conducting parameterization processing on the link relation of the key positions; performing finite element mesh generation on the three-dimensional model to obtain a finite element model; conducting kinetic analysis on the rail-mounted inspection robot driving mechanism, and obtaining an analysis result; and judging whether the maximum equivalent stress and the maximum deformation of the structure meet preset conditions or not. The problem of repeated work and time caused by repeated design and sample piece machining during structure optimization in the development process of a traditional inspection robot is solved, and repeated test verification is avoided for different optimization schemes, so that the research and development and optimization time is shortened, the development expenditure is saved, and theanalysis precision is improved.

The invention discloses a finite element mesh generation method for a honeycomb sandwich panel with pit defects. The finite element mesh generation method comprises the following steps: calculating the number of honeycombs of the honeycomb sandwich panel in length and width directions; constructing geometric models of various components of the honeycomb sandwich panel; generating a geometric model of the honeycomb sandwich panel; generating a honeycomb sandwich panel finite element mesh model; generating a pit defect; and acquiring a finite element mesh model of the honeycomb sandwich panel with the pit defect. According to the finite element mesh generation method, the finite element mesh model of the corresponding honeycomb sandwich panel can be automatically constructed as long as the boundary dimension of the honeycomb sandwich panel with the pit defect is given; as long as pit defect parameters are given, the finite element mesh model of the corresponding honeycomb sandwich panel with the pit defect can be automatically constructed; and thus, technical support can be provided for efficiently carrying out comparative analysis work on the influence of different pit defect parameters on the mechanical properties of the honeycomb sandwich panel, and the method is particularly suitable for being applied to mechanical property evaluation of the honeycomb sandwich panel with the pit defect.

The invention discloses a numerical simulation calculation method for a multi-layer and multi-pass welding process of a header tube socket. The method comprises the following steps: S1, establishing a three-dimensional thermal coupling calculation model of a tube socket, a header and a welding seam, and performing finite element mesh generation on a solid model of the header tube socket weldment to form a plurality of mesh units of the solid model; S2, setting initial conditions and boundary conditions of the welding model; S3, determining a heat source equation and welding parameters used by the saddle-shaped welding seam of the header pipe base; and 4, submitting and solving the task, and carrying out post-processing and analysis. According to the structural features of the saddle-shaped welding seam of the tube socket header, the entity model is established in a targeted mode, grids are divided in a regional mode, welding heat source parameters are corrected, the change rule of a post-welding temperature field and a stress-strain field can be predicted, and the actual saddle-shaped welding seam welding process is guided.