472 results about "Finite element analyse" patented technology

Methods of selecting a configuration of fixation and compression screws for a bone plate to be installed on a bone of a patient. A computer or website allows a user to load images of a fractured bone and specify a particular configuration of fixation and compression screws with a plate on the loaded bone. The computer replicates stresses imposed on the bone by regular activities using finite element analysis and provide information about the suitability of the selected configuration.

A finite element pre processing method for reconstructing a three-dimensional entity model comprises the steps that first, a material object is scanned so that point cloud data can be acquired; second, the point cloud data are imported to 3-matic software, and the position of the model is adjusted; third, the point cloud data are de-noised and sampled; fourth, three-dimensional reconstructing of the point cloud data is performed through a computer, wherein the point cloud data are packaged so that a surface mesh model can be generated; fifth, thin wall characteristic analysis is performed on the model so that a basic model structure can be known; sixth, three-dimensional repair is performed on model meshes, so that the edges of the model are matched with the defect contour of the material object; seventh, the model is redesigned as required, and thus the structure of the model can be more reasonable and meet the design requirement; eighth, the meshes of the redesigned model are partitioned again; ninth, a volume mesh is generated, material attributes are added, and the new model is saved in the format through which finite elements can be directly analyzed; tenth, finite elements are analyzed. Through the method, the scanned data processing time is shortened and FEA/CFD pre processing time are shortened, and optimal design of the model can be conveniently performed.

The invention discloses a method for optimizing the internal structure of a 3D (Three-Dimensional) printed object. According to the method, based on Voronoi diagram and FEM (Finite Element Analysis Method), the stress diagram of a model under external force is calculated through the FEM, and an internal structure similar to honeycombs is calculated and generated in combination with the stress diagram through the Voronoi; the honeycomb-shaped structure can minimize consume materials while providing excellent structural strength, materials can be saved in the 3D printing process, and the internal structure similar to honeycombs of printed object can be endowed, given external force is supported, and the object is firmer and more solid.

The invention provides a method for constructing a vertebral three-dimensional geometry and finite element mixture model, which belongs to the technical field of processing of medical images. The method comprises the following construction processes of: inputting a vertebral computer tomography (CT) image; performing three-dimensional reconstruction and three-dimensional cutting on the CT image to acquire a vertebral three-dimensional image set; establishing a three-dimensional geometric statistical model, namely defining and manually calibrating vertebral characteristic points, aligning and registering vertebral images, and training a sample set to acquire the statistical model; and generating a finite element model, importing the statistical model, generating a surface mesh model, and generating a volume mesh model, wherein the model can be directly imported into finite element analysis software for biomechanics analysis. By the method, a vertebral geometrical shape can be precisely described, the accuracy of finite element analysis results can be ensured, and the precision of vertebral models can be improved. The method is convenient to use, facilitates the scientific measurement of the shapes and the stress of vertebras and can be used for researches related to vertebral columns and the vertebras in the field of surgical medicine.

The temperature distribution associated with a design of an integrated circuit is calculated by convoluting a surface power usage represented by a power matrix with a heat spreading function. The heat spreading function may be calculated from a simulation of a point source on the integrated circuit using a finite element analysis model of the integrated circuit or other techniques. To account for spatial variations on the chip, the heat spreading function may be made dependent on position using a position scaling function. Steady-state or transient temperature distributions may be computed by using a steady-state or transient heat spreading function. A single heat spreading function may be convolved with various alternative power maps to efficiently calculate temperature distributions for different designs. In an inverse problem, one can calculate the power map from an empirically measured temperature distribution and a heat spreading function using various de-convolution techniques. While the forward problem is analogous to image blurring, the inverse problem is analogous to image restoration.

The invention provides a digital prototyping design integrated development method which comprises the steps of: establishing a digital prototyping parameterization design model and a digital prototyping finite-element analysis optimization model in a database; synchronously sharing same parameters between the models; calling the digital prototyping parameterization design model in the database for carrying out parameterization design; changing parameters of the digital prototyping parameterization design model according to object characteristics and synchronously changing same parameters in the digital prototyping finite-element analysis optimization model; calling the digital prototyping finite-element analysis optimization model in the database for carrying out finite-element analysis optimization design; and extracting parameters of the digital prototyping finite-element analysis optimization model from the database, automatically forming a finite-element analysis command stream, generating a structure geometrical model, establishing a finite-element model, carrying out structure analysis optimization, and correcting corresponding parameters after analysis optimization. The invention provides a digital prototyping design integrated development method and system which are used for reducing workload of product design.

The invention discloses a method for dynamic modeling on an entire numerical control machine tool based on kinetic parameters of a joint part and analyzing and optimizing dynamic performance and an implementation scheme. The method disclosed by the invention takes a certain type of a vertical machining center as an example, dynamic model building and parameter identification are carried out on a bolt joint part, a guide rail sliding block joint part, a ball screw joint part and a bearing joint part, the dynamic performance of the entire numerical control machine tool is analyzed by combining finite element analysis software, an optimization object is established on the basis, a multi-objective optimization model is constructed, and the best optimization configuration is solved, so that the dynamic performance of the entire numerical control machine tool is optimized. Achievements of the method disclosed by the invention can be used for solving problems finite element analysis and optimization on the dynamic performance of the entire numerical control machine tool, and technical support is provided for improving processability of the numerical control machine tool.

The invention relates to a probabilistic finite element method (PFEM)-based steel-bride fatigue reliability evaluation method, in particular to a fatigue reliability evaluation method by combining dynamic weighing data (WIM) of a car and the analysis of the PFEM, which aims at solving the problems that the bridge structure health monitoring cost is higher and the stress measuring point distribution is limited, and utilizes the real WIM data to statistically analyze car load and establishes a probabilistic distribution model of a car type, road distribution, axle weight and wheel-base. Finite element method analysis software is used for establishing a numeric model of a bridge. A probabilistic finite element program is compiled, stress amplitude and stress cyclic quantity of a key part under the random car load effect are extracted through the sampling, loading and finite element analysis to be statistically counted. The fatigue reliability calculation is performed according to the statistical result, and the reliability attenuation trend of the evaluated part in the subsequent application process is predicted. By adopting the method, a feasible analysis tool is provided for the fine fatigue evaluation of complicated steel-bridge details.

The invention relates to a finite element analysis-based variable-element permanent magnet synchronous motor modeling method which comprises the following steps of constructing a three-dimensional finite element electromagnetic field simulation model of a permanent magnet synchronous motor, and performing transient field road coupling analysis on the three-dimensional finite element electromagnetic field simulation model to obtain a large quantity of characteristic parameters; creating an improved permanent magnet synchronous motor voltage equation and a torque equation; constructing a simulation model of the permanent magnet synchronous motor according to an improved permanent magnet synchronous motor math model; leading all the obtained characteristic parameters into corresponding ports of the simulation model to construct a finite element analysis-based variable-element permanent magnet synchronous motor dynamic simulation model. The permanent magnet synchronous motor model modeled by the method disclosed by the invention comprehensively considers the magnetic field saturation effect, the d-q axis cross coupling effect, the eddy current effect, the hysteresis effect and the like; the instantaneity is considered, and the accuracy of the permanent magnet synchronous motor model is improved; the permanent magnet synchronous motor model is particularly suitable for the research on the dynamic processes such as power failure-bepelt and three-phase sudden short circuit of the permanent magnet synchronous motor.

The invention relates to a correction method for preventing excessive stress concentration of teeth roots and jaws in the process of orthodontic treatment, belonging to the technical field of orthodontics of teeth. The correction method comprises the following steps of: establishing an automatic-matching 3D (three dimensional) integrated tooth-jaw model; carrying out stepwise virtual correction on the 3D integrated tooth-jaw model; applying 3D finite-element analysis to determine the dynamic change of stress distribution of the teeth roots and the jaws in the whole process of the virtual correction and guarantee that the stress of the teeth roots and the jaws in correction is in the safety range; and manufacturing a clinical correction device by a fast laser forming technology. By the individualized correction device designed and manufactured by a computer in an auxiliary manner, the positions and the routes of movement of the teeth roots can be controlled. By expression and verification, the correction method can duplicate the condition of virtual correction in actual treatment, realizes good position relation among the teeth roots, the teeth and the jaws in the correction process, and is beneficial to reducing and eliminating absorption of the teeth roots and the alveolar bones due to excessive stress concentration in the process of orthodontic treatment and reducing and avoiding recurrence after correction.

The invention relates to a method for quantitatively analyzing material interface properties by combining non-destructive testing and definite element modelling. In the method, by loading a composite material, a non-destructive testing system records a loading variable; and at the same time, a finite element method correspondingly simulates the whole loading process of a test piece according to intrinsic properties, modulus, tensile strength, Poisson ratio and the like of the material so as to find a simulation state corresponding to the non-destructive testing variable and further obtain comprehensive analysis results, including various physical quantities reflecting the material interface properties such as friction coefficient between fibers and a matrix, stress, straining, counterforce and the like, in the simulation state. The non-destructive testing high-precision method verifies partial parameters of finite element analysis, and the finite element analysis provides more comprehensive analysis results. The method has the advantages of high sensitivity, credible quantitative values and no need of damaging an adhesive layer.

The invention discloses a three-point support optimization design method of a machine tool bed based on a response surface model. The method comprises the steps that a simplified model of a bed structure is established in CAD (Computer-Aided Design) software; three-point support limiting positions are found; a variable design space and an optimization objective are determined; test sample points for statics analysis are selected from the design space, and subjected to the statics analysis by finite element analysis software; a response value is calculated and extracted; a second-order response surface model, reflecting an input-output relation of structural design, of deformation at guide rails of the bed is established according to the response value; an optimal solution of the response surface model is acquired by a genetic algorithm; based on the established second-order response surface model, three-point support positions when the deformation of the guide rails is minimum are found; a practical model of the bed is subjected to the statics analysis; and the reliability of three-point support optimization design is verified. With the adoption of the method, the deformation of a machine tool is reduced; the machining precision of the machine tool is improved; the three-point support optimization efficiency and the optimization precision are improved; and the problems that the calculation amount is large, the efficiency is low, and an optimal result cannot be ensured easily in the existing optimization technique are solved.

The invention discloses an additive manufacturing-based product lightweight design method. The method comprises the following steps: 1, establishing a parametric porous structure database, and establishing corresponding relationships between various parametric structures and mechanical property; 2, carrying out finite element analysis on an original product model structure; 3, adjusting a parametric unit structure to satisfy difference demands, for the mechanical property, of different mesh regions in the product; 4, carrying out filling replacement on the regions with excess performance in the products by using a lightweight unit structure; 5, carrying out mechanical property check on a lightweight product structure through finite element analysis. According to the method disclosed in the invention, the finite element analysis and the gradient distribution design of a parametric porous structure are combined, and different lightweight strategies are adopted in allusion to the performance demands of different parts of function parts under the premise of satisfying the mechanical property, so that the reasonable and efficient lightweight design is realized, and lightweight products can be prepared by using an additive manufacturing method.

Systems and methods of simulating an explosion in time-marching finite element analysis are disclosed in the present invention. According to one aspect, a method is configured for increasing user (e.g., engineer or scientist) productivity by reducing computation time of simulating fluid-structure interaction due to an explosion. The method comprises a creation of a finite element analysis model that includes structure, surrounding fluid, a blast source of the explosion and a single layer of ambient elements each having a segment representing a boundary of the fluid facing the blast source. Each ambient element is associated with a particular finite element representing the fluid at the boundary. The ambient elements are configured to be situated between the blast source and the structure such that the simulation can be carried on a set of boundary conditions specified thereon. The boundary conditions comprise a set of nodal velocities that are determined from the empirical formula (e.g., Friedlander equation).

The invention discloses an automatic data conversion method between a three-dimensional modeling software and a finite element analysis software, which comprises the following steps of starting the finite element analysis software, loading the model and performing finite element analysis; starting the three-dimensional modeling software in the finite element analysis software; reading files and performing finite element analysis in the finite element analysis software; saving the result in format of data file by utilizing a data post-processing module and the read and write function of the finite element analysis software; and circularly running the above processes by utilizing the process control command of the finite element analysis software. The automatic data conversion method achieves seamless integration of the powerful modeling function of the three-dimensional modeling software and the finite element function of the finite element analysis software and provides a scientific, high-efficiency and reliable solution for design and analysis of a complicated mechanical system, thereby increasing the product design accuracy and design efficiency.

Systems and methods of limiting contact penetration in numerical simulation of non-linear structure response using implicit finite element analysis are described. According to one aspect, a finite element analysis (FEA) model of a structure is defined as a number of nodes and elements based on geometry and material properties of the structure. A time-marching analysis of the FEA model is then performed. The time-marching analysis results contain a number of solutions of non-linear structure response at respective time steps. Solution at each time step requires at least one iteration to compute. Non-linear structure response is determined in the following manner: 1) determining a search direction; 2) calculating a contact penetration parameter in the search direction; and 3) finding a minimum energy imbalance location along the search direction as a solution which is further restricted by the CPP such that contact penetration of the structure is substantially limited.

The invention discloses a finite element theory based direct current magnetic bias suppression method under the condition of multiple direct-current falling points, and belongs to the field of direct current electric fields. According to the method, direct current electric fields are calculated with a finite element analysis method, the resistance in the direction parallel to the axis is obtained by calculating the radial resistance of the assigned specified soil grid, the distribution tendency of voltages and currents in the assigned direction is obtained, the current fields in different current falling points are determined, and the CDEGS software is adopted as a verification means; the current distribution curves corresponding to a plurality of directions are obtained to serve as the technical base for adopting the corresponding direct current magnetic bias suppression scheme in the following steps. Magnetic bias current calculating sub-models oriented to different power transmission systems can be respectively formed, the coverage range of the direct current magnetic bias research and the direct current magnetic bias suppression scheme is widened, and the simulating calculating efficiency is greatly improved. The method can be widely applied to the field of design, running and management of extra-high-voltage direct current power transmission lines.

Methods, systems and computer program products for assessing residual life of an airfoil, which would experience high cycle fatigue failure under at- or near-resonance vibration condition, are provided. The method includes receiving, at a processing system, at least one vibration response parameter associated with the airfoil. The method processes at least one cracked airfoil finite element model. Processing the cracked airfoil finite element model includes accessing the cracked airfoil finite element model, computing a modal stress intensity factor (SIF) of the cracked airfoil finite element model using fracture mechanics based finite element analysis, and computing a vibratory SIF based, at least in part, on the modal SIF and the at least one vibration response parameter. The method then computes a residual life indicator of the airfoil based, at least in part, on the vibratory SIF.

The invention provides a structure optimization design method which comprises the following steps: establishing an optimization design objective function and constraint conditions; establishing structure optimization design regions; initializing an optimization model; carrying out structural finite element analysis on the model, and calculating values of the objective function and the constraint equation according to the analysis result; analyzing the shape sensitivity, and updating the model in an appropriate evolution algorithm according to the analysis result; and carrying out other operations to ultimately obtain the optimal structure model. The invention also provides a software system using the optimization design method. The software system sufficiently implements the optimization algorithm and simultaneously provides a favorable user interface and a data interface. The optimization design method and system provided by the invention can be directly used for computer-aided design, has low grid dependence and is applicable to various common objects.

The invention belongs to the field of power system overhead transmission line tower safety monitoring, and provides a transmission tower online safety monitoring system and method for stress measuring. Firstly, stress sensors are installed on the key parts of a tower, and installation points can be obtained through finite element analysis and load application. Measurement values of the stress sensors are transmitted to a background server through the internet, the background server works out the reliability of each section of main material in real time according to each group of data together with the mean value and the variance of the strength of steel materials, and therefore the overall reliability of the tower can be obtained. The transmission tower online safety monitoring system and method have the following advantages that the problem of real-time tower stress monitoring is solved, and the stress distribution situations of the key parts can be monitored in real time; the safety state of the tower can be estimated in real time and serious accidents such as collapse can be effectively prevented under severe working conditions; research results are wide in application and can be directly applied to various tower shapes.

A method for defining at least one parameter for a finite elements analysis (FEA) calculation in a computer-assisted drafting (CAD) program comprises the steps of determining a body for which said parameter is to be defined, said body being a entity processed by said CAD program; and using at least one graphical function of said CAD program to define a region within a face of said body, said region being used to define a load/support condition for said FEA calculation. A computer program product and an apparatus comprise corresponding features. The present invention provides an improved way of defining parameters like load or support conditions for an FEA calculation in a CAD program.

The invention discloses a method for automatically converting data between dynamics analysis software and finite element analysis software, comprising the following steps of: starting the finite element analysis software to perform model flexiblization and outputting a modal neutral file (MNF); starting the dynamics analysis software, loading a virtual prototype model, reading the MNF, performing kinematics and dynamics analysis and outputting a load file; applying a load in the load file to a flexible body, performing stress and strain analysis on the flexible body and outputting stress and strain data; and circularly performing the steps and outputting an optimal operating condition and the stress and strain data. The method for automatically converting data can really integrate the powerful finite element function of the finite element analysis software and the powerful dynamics analysis function of the dynamics analysis software for combined application and provide an automatic, simple, convenient, high-efficiency and reliable realization means for achieving the mechanical property analysis and the operating condition analysis of a mechanical system.