49 results about "Finite element computation" patented technology

The application belongs to the field of computational mechanics, and discloses a scale order reduction near-field finite element calculation acceleration method and implementation method for structure fracture analysis.The acceleration method comprises the following steps: firstly, geometric modeling is performed on a target structure; secondly, the split finite element is recorded as a fine scale element and constitutes a fine scale grid; thirdly, based on a spatial neighborhood relationship, the fine scale element is collected into a coarse scale element and constitutes a coarse scale grid; fourthly, an equivalent shape function of the coarse scale element is obtained; fifthly, the overall stiffness matrix and the load vector of the coarse scale grid are calculated; sixthly, the overall node displacement of the coarse scale and fine scale grid is solved; seventhly, it is judged whether the current loading step or time step reaches the maximum loading step or time step; if yes, the displacement nephogram and equivalent damage nephogram of the target structure are output; if not, the key state of all fine scale near-field elements is updated; and finally, the implementation method is that the acceleration method is taken as a core calculation module to be implemented in different scenes.The application significantly improves the calculation efficiency of near-field dynamics in large-scale simulation analysis.

This invention discloses a rapid electromagnetic-thermal coupling optimization method for permanent magnet motors considering demagnetization. Specifically, it involves finding an initial topology for the permanent magnet motor that satisfies the temperature rise condition after electromagnetic-thermal coupling calculations, and obtaining the average temperature rise of each component of the motor. This temperature rise is then fixed in the parametric electromagnetic model of the motor, and the motor efficiency is calculated using LHS sampling and finite element method. or With the degree of demagnetization D m Furthermore, a demagnetization penalty term is introduced into the efficiency calculation. D m Mapped to a 01 array, denoted as D m_01 Using efficiency data and demagnetization data D m_01 The Kriging response surface and the decision tree response surface were trained separately. Using demagnetization as a constraint, the motor efficiency was optimized and validated using NAGA-II. If the accuracy of the efficiency response surface was insufficient, it was trained and optimized again to enhance its predictive ability in the high-efficiency region of the motor. Electromagnetic-thermal coupling calculations were performed using the highest-efficiency topology predicted by the efficiency response surface to obtain the efficiency. or re .like or re If the requirements are met, the optimization ends; if not, a new round of optimization begins, and this cycle continues.

This invention discloses a three-dimensional finite element simulation method for underground caverns that considers the dynamic evolution of surrounding rock deformation parameters. Based on triaxial loading and unloading tests of the surrounding rock in an underground cavern, the method first obtains the evolution equations of the surrounding rock deformation parameters under different stress paths, then constructs a three-dimensional finite element calculation model of the underground cavern. Through secondary development technology of finite element software, the evolution equations are embedded into the simulation process, realizing real-time dynamic adjustment of the deformation modulus and Poisson's ratio of the surrounding rock as the stress state changes during excavation. During the simulation, the method cyclically executes "stress monitoring - path judgment - parameter calculation - model assignment - convergence calculation" according to the excavation step sequence until the cavern excavation is completed. This invention restores the deterioration law of surrounding rock parameters under unloading during underground cavern excavation, improves the fit between numerical simulation results and engineering reality, and provides a reliable basis for the stability analysis of the surrounding rock and the design of excavation and support schemes for underground caverns.

The application discloses a kind of based on residual stress threshold value corrosion cracking resistance heat treatment optimization method, belong to heat treatment numerical simulation research technical field, to solve the problem of high risk of stress corrosion cracking in weld heat-affected zone.Method includes determining the postweld residual tensile stress of inner wall weld heat-affected zone according to the cylindrical structure and physical properties of different materials;Four-point bending specimen is prepared, and target sample is prepared by annealing and bending moment loading;Residual tensile stress is loaded and finite element calculation is carried out for loading displacement;The residual stress threshold value of corrosion cracking is defined by electrochemical test on target sample;According to residual stress threshold value and combined with heating strip width basic formula, heat-mechanical coupling finite element simulation is carried out, and the optimized width correction coefficient is screened, to obtain the adaptive heating strip width design formula and complete optimization.The application can accurately determine the residual stress threshold value, optimize the heating strip width, improve the corrosion cracking resistance of component, and has economy and industrial value.

This invention relates to a method and system for improving the constructability of inclined 3D printed concrete based on finite element simulation. The method includes: modeling the inclined 3D printed structure, performing strip division, segment division, and mesh division to obtain the target model, constructing a set of elements and nodes for each segment, and setting the model parameters of the target model; activating the element set, nozzle constraints, and extrusion pressure of the corresponding segment segment by segment, assigning age variables to the activated nodes, and applying gravity to the activated parts; performing finite element calculations on the segment-by-segment activation process until the structure is significantly damaged, obtaining the maximum printable height and corresponding deformation before damage; adjusting the process parameters, remodeling if the initial inclined 3D printed geometry changes, otherwise resetting the process parameters until the maximum printable height is maximized and the corresponding deformation is minimized. Compared with the prior art, this invention improves the current situation where existing models have insufficient fidelity in reproducing the inclined 3D printed concrete process and low prediction accuracy.

This invention provides a finite element method for modeling wind turbine hubs, comprising the following steps: acquiring a 3D model and importing it into finite element software for preprocessing to establish a finite element model; coupling the bearing mounting surface nodes of the main shaft to the geometric center through a rigid domain and applying constraints to the coupled nodes; establishing bolted connections between the pitch bearing and the hub, and between the blade root and the pitch bearing, and applying preload to the bolts; establishing a rigid connection between the blade root center and the blade root end face, and applying a load to the blade root center; using a simplified slice model to simulate the stiffness, clearance, and profile of the rollers within the finite contact length of the rolling elements; and numerically compensating for the clearance and profile of the slice springs using stiffness curves. This method overcomes the limitations of existing hub finite element models, such as inaccurate pitch bearing contact angle capture, unclear pitch gear meshing load transmission, and the influence of boundary conditions and bolted connections on the hub stress distribution, resulting in a more accurate stress distribution for the hub.

The application provides a fatigue crack life prediction method and system based on a physical information neural network, comprising: a data acquisition step: through finite element numerical simulation, crack length and fatigue life expansion data under different working conditions are acquired; a data set construction step: a data set for training a neural network is constructed according to the expansion data; a neural network construction step: according to the data set, a physical information neural network is constructed and trained to obtain a physical information neural network model; a life prediction step: inputting working condition parameters to be measured into the physical information neural network model, fatigue crack prediction results are obtained and outputted. The application solves the problems of long time consumption of finite element calculation and data dependency of a data-driven model, and realizes accurate prediction of fatigue crack expansion residual life under a small sample.

This invention relates to the fields of materials science and parts forming and manufacturing technology, and discloses a method and system for cross-scale prediction of material mechanical properties. The method includes: acquiring EBSD data of the modeling material; extracting first-class microscale features (crystal orientation, phase distribution) and second-class microscale features (SF, TF, grain size, texture); constructing an RVE model based on the first-class features; embedding the crystal plastic constitutive model for finite element calculation to obtain the macroscopic mechanical response and grain-scale stress-strain distribution; combining the calculated data, selecting at least one feature from the two classes as input to establish a quantitative prediction model for macroscopic mechanical properties; for the target material, acquiring its EBSD data and extracting corresponding features, and applying the model to predict macroscopic mechanical properties. This invention achieves direct quantitative prediction from microscopic mechanisms to macroscopic properties, reducing reliance on large-scale experiments and providing an efficient and reliable tool for materials design and process optimization.

The application provides a kind of integrated intelligent design method of electric truck aluminum alloy frame, belongs to the technical field of automobile structure design.The method comprises the following steps: establishing a collaborative parametric finite element model of the frame, unifying the structural size, section shape and bolt connection parameters as design variables, and obtaining a performance sample set; based on MLP, an agent model is constructed to predict the frame mass, fatigue life, modal, displacement and stress response; a PPO-enhanced NSGA-III algorithm is used for multi-objective optimization, and the PPO dynamically adjusts the crossover and mutation parameters to obtain a Pareto candidate solution; and then the CRITIC-TOPSIS algorithm is used to select the best design scheme. The application can reduce the amount of repeated finite element calculation, improve the efficiency of high-dimensional multi-objective optimization, and achieve the collaborative balance between frame lightweight, stiffness, strength, modal performance and fatigue life.

The application discloses a smooth finite element-Newmark calculation method for underwater target transient acoustic scattering, and belongs to the technical field of underwater transient acoustic scattering numerical simulation. First, a calculation domain of an underwater transient acoustic scattering field is discretized into a standard quadrilateral element grid, and an acoustic pressure field interpolation format is constructed. The quadrilateral element is divided into multiple smooth domains, a smooth acoustic pressure gradient field is obtained through acoustic generalized gradient smoothing technology, and a smooth acoustic pressure gradient matrix is obtained through Gaussian integration. A system matrix equation is constructed in combination with a transient acoustic scattering control equation and a Galerkin weighted residual value method. A parameter-optimized Newmark time integration method is used to complete time domain discretization and recursive solving, and numerical results of the transient acoustic scattering field are obtained. The application softens the system stiffness matrix through gradient smoothing technology, reduces spatial discretization error, eliminates time domain false numerical damping, and has higher precision than the standard finite element method under the same grid, thereby providing an efficient and reliable scheme for underwater transient acoustic scattering engineering calculation.

The application belongs to the technical field of three-dimensional electromagnetic radiation numerical solution, and relates to an electromagnetic radiation simulation analysis method based on local grid self-adaptive division. Firstly, the application carries out finite element modeling on a target antenna, introduces PML boundary and wave port excitation to establish a corresponding finite element calculation domain model, and adopts tetrahedral grid division to classify the calculation domain model; then finite element electromagnetic radiation simulation analysis is carried out to obtain finite element solution, and error estimation and encryption strategy are used to give the encryption size of the grid nodes in the non-PML region; finally, the grid is encrypted, finite element electromagnetic radiation simulation analysis is carried out again, and the process is repeated until the overall solution error is less than the set error limit, the final calculation grid is obtained, and finite element electromagnetic radiation simulation analysis is carried out. The application only encrypts the tetrahedral grid in the non-PML calculation domain, ensures the original characteristics of the tetrahedral grid in the PML calculation domain, and realizes the rapid simulation design of the antenna radiation characteristics while ensuring the calculation accuracy.

The application relates to the technical field of tumor hyperthermia, in particular to a temperature field acquisition method and device for tumor thermal ablation surgery, wherein the method comprises the following steps: segmenting a three-dimensional tumor model from a three-dimensional magnetic resonance image in a target liver; calculating the centroid position of the three-dimensional tumor according to the three-dimensional tumor, and solving the ellipsoid parameters of the three-dimensional tumor; querying a preset database by using the ellipsoid parameters to obtain the closest ellipsoid data, and acquiring the current temperature field distribution from the closest ellipsoid data. Therefore, the problems in the prior art that the finite element calculation is huge in amount, time-consuming, and the temperature field cannot be acquired and monitored in real time, the accuracy and real-time performance of the surgery are reduced, and the requirements of the tumor thermal ablation surgery cannot be met are solved.

The application discloses a thermal-mechanical fatigue crack propagation rate testing method based on rigidity and crack tip strain field, comprising the following steps: firstly, a relationship function between normalized crack length and normalized rigidity is established through finite element calculation; secondly, DIC speckle preparation is carried out for observing crack propagation and strain field analysis; then, a thermal-mechanical fatigue test is carried out, crack length is calculated based on rigidity change results of the test, an a-N relationship curve is drawn combined with DIC synchronous observation results, and comparative analysis is carried out; finally, crack propagation rate is calculated through a three-point moving average secant method, and the size of a plastic zone at a crack tip is determined according to DIC strain field analysis, so that the accurate test of the crack propagation rate is realized. The application can effectively test the fatigue crack propagation behavior under the thermal-mechanical coupling effect, and accurately obtain the thermal-mechanical fatigue crack propagation rate combined with the crack tip strain field measurement method, so as to provide test data support for damage tolerance design and structure integrity evaluation of high-temperature pressure-bearing equipment.

This invention discloses an intelligent optimization algorithm for curved fiber wing that integrates physical information buckling proxy, relating to the field of aircraft design technology. The method includes: equivalently planarizing the spatially twisted quadrilateral; deriving the Jacobian matrix through a double-triangle affine mapping to construct a variable stiffness total potential energy functional; embedding the mechanical control equations using a physical information neural network (PINN) to quickly solve for the buckling critical load factor and modes, replacing traditional finite element calculations; parameterizing the fiber path and thickness to construct design variables; and employing a multi-stage adaptive differential evolution algorithm for global optimization, integrating process, static / dynamic aeroelasticity, and strength constraints. This invention achieves a closed-loop modeling-evaluation-optimization process, significantly reducing computational costs while maintaining mechanical consistency, solving the convergence problem of high-dimensional variable coupling, and greatly improving the automation and engineering efficiency of curved fiber wing design.

The application discloses a tapered roller bearing entity simulation method and device, equipment and medium, and relates to the technical field of wind power generation. According to the scheme, a TRB entity model is constructed, and a frictional contact is set between a large-end spherical base surface of a tapered roller and a large flange of an inner ring, so that the contact pressure of the large flange and the roller posture are truly reflected. The central region of the large-end spherical base surface is connected to the corresponding position of the large flange of the inner ring only through a spring unit, and the included angle between the axis of the spring unit and the vertical central section of the tapered roller is less than a preset threshold value, so that the constraint direction is concentrated on the local limiting direction of the spherical base surface and the large flange, and the non-physical rigid body drift in the frictional contact establishment process is inhibited. The spring counterforce is less than the contact force of the corresponding tapered roller, and the spring unit is not connected to the outer ring of the bearing, so that it is only used for numerical stability and does not participate in the main load transmission, and does not interfere with the main bearing contact between the roller and the raceway, so that the convergence stability of the finite element calculation is significantly improved while the contact authenticity is ensured.

The application discloses a kind of whole hollow composite multi-point low-speed impact damage behavior prediction methods, belong to the field of impact simulation analysis of composite material structure.The method of the present application comprises: according to CT scanning, the establishment whole hollow composite cell model, based on cell model establishes panel micro model and divides tetrahedron grid, gives material attribute, to meet displacement continuity and stress continuity, obtains panel mechanical parameter, based on the obtained panel mechanical parameter establishes macroscopic micro-coupling finite element model, to model is applied first and second low-speed impact load and carries out finite element calculation, obtains damage behavior.The present application can accurately predict the damage behavior of whole hollow composite under multiple low-speed impact load, and can provide theoretical basis for composite structure design and engineering application.

This invention proposes a centering method and system for a single-bearing stern tube ship propulsion system. First, a method for characterizing the main engine's attitude adjustment is established. Second, a model structure relating the adjustment and verification quantities for centering the single-bearing stern tube ship propulsion system is proposed. Finally, the values ​​of key verification quantities under different main engine attitudes are calculated using finite element analysis. A training sample set is obtained and used to train the relational model, which is then applied in the finite element model to verify its effectiveness in guiding actual centering. This invention eliminates reliance on human experience, transforming manual decision-making into model-based decision-making, and improving the accuracy and efficiency of centering adjustments for ship propulsion systems.

A large thin-walled part overall deformation sub-region compensation method based on space-time interaction. The influence range of space-time interaction on deformation in the region is demarcated, and a deformation reference point is set in the region; considering the influence of initial stress release and processing stress introduction, an interaction model between regions is established; an analytical method of space-time interaction coefficient is proposed, and the offset value of the reference point is solved by using finite element analysis means; the compensation region is divided by the gradient of the offset value change, the boundary intersection points of the region are defined as characteristic reference points, the characteristic reference point positions are obtained by in-machine measurement method, and the difference between the characteristic reference point positions and the finite element calculation positions is calculated to correct the region compensation value; the processing code in the region is offset as a whole according to the compensation value, and the overall deformation compensation of the large thin-walled part is completed. The invention proposes the concept of space-time interaction coefficient, and the overall offset of the region processing track completes digital processing, which is simple in whole process operation, high in automation degree and effectively improves the machining precision, and meets the demand of overall deformation precision control of large thin-walled parts.

The application discloses a smooth finite element-Bathe calculation method for underwater target transient acoustic scattering, and belongs to the technical field of underwater transient acoustic scattering numerical simulation. Firstly, a sound scattering field calculation domain is discretized into a quadrilateral element grid, and an acoustic pressure field interpolation format is established; then, an element smooth domain is divided, a smooth acoustic pressure gradient matrix is obtained through acoustic generalized gradient smoothing technology, and a system matrix equation is constructed in combination with a transient acoustic scattering control equation and a Galerkin weighted residual value method; time domain discretization is completed through the Bathe time integration method, and iterative solution is carried out, so that full-time domain numerical results of the transient acoustic scattering field are obtained. Through the gradient smoothing technology, the spatial discretization error is reduced, error cooperative suppression is realized in combination with the frequency self-adaptive numerical damping of the Bathe integration method, the precision is higher and the stability is better than those of the standard finite element method under the same grid, and an efficient and reliable scheme is provided for underwater transient acoustic scattering engineering solution.

This invention provides a finite element parametric modeling method for a manned lunar rover's metal mesh wheel, comprising the following steps: Step S1, providing model parameters for the woven wheel; Step S2, obtaining the curve parametric equations describing the position and shape of each metal wire; Step S3, calculating the intersection points between every two metal wires, and determining the position coordinates of the metal wires in contact state based on their spatial position and diameter; Step S4, calculating the node information and element information of the finite element model; Step S5, generating a text-formatted finite element model file; Step S6, importing the model into finite element calculation software, setting loads and boundary conditions, and performing calculations. This invention directly generates a finite element mesh based on the geometric characteristics of the metal wires, greatly shortening the modeling time; it achieves parametric finite element modeling, enabling the generation of new finite element models based on information such as weaving angle, number of metal wires, mesh size, and wheel cross-section, which is highly beneficial for rapid iteration in the wheel design stage.

The present disclosure provides a mechanics calculation method and apparatus for a pipeline. The method includes: generating a pipe-beam model formed by connecting a plurality of pipe-beam elements; generating a target shell component mesh model formed by joining a plurality of shell elements; replacing, with the target shell component mesh model, a pipe-beam element at a corresponding position in the pipe-beam model to form a hybrid model; performing finite element calculation on the hybrid model to obtain a displacement of each node of the hybrid model; calculating nodal internal forces of the pipe-beam elements based on nodal displacements of the pipe-beam elements; calculating stresses of the respective shell elements based on mesh nodal displacements of the target shell component mesh model; and calculating stresses of the pipe-beam elements based on the nodal internal forces of the pipe-beam elements.

The genetic algorithm-based large prestressed continuous beam aqueduct optimization design method of the application comprises the following steps: constructing multi-dimensional design variables and generating a high-fidelity training data set; adopting hybrid coding chromosome to represent design individuals, executing geometric interference self-healing logic and engineering modulus normalization; constructing a full working condition matrix, converting concrete shrinkage, concrete creep and prestress long-term loss into response correction amounts respectively and establishing a constraint judgment library; training an agent model as a transient evaluation engine; adopting an adaptive genetic algorithm for global optimization, maintaining a Pareto non-inferior solution set; screening the optimal scheme for high-fidelity review and selective incremental learning. The application realizes millisecond-level reasoning through an AI agent model, solves the bottleneck of frequent calling of finite element calculation in traditional methods, ensures the constructability of the scheme through self-healing logic and modulus normalization, guarantees the whole life cycle performance through full working condition time-varying effect evaluation, and forms a closed-loop evolution through active learning and high-fidelity review, thereby improving the optimization efficiency and search depth on the premise of ensuring safety and compliance.

This invention relates to the field of bridge design and construction technology, specifically to an integrated method for determining construction parameters of tied-arch bridges based on multi-stage collaborative simulation. The method includes constructing a finite element model A based on the structural dimensions and load parameters of the arch ribs, tie beams, and hangers of the tied-arch bridge; iteratively calculating the target cable force vector of the hangers based on finite element model B; calculating the target internal force vector of each hanger after installation based on finite element model C and the target cable force vector; determining the initial tension force vector of the hangers based on finite element model A and the target internal force vector; installing each hanger in the tensioning sequence in finite element model D; applying tension force to each hanger according to the initial tension force vector; calculating the stress-free cutting length of each hanger; extracting the deflection deformation data of the tie beam under a dead load + 0.5 times the vehicle live load through finite element calculation; and setting the pre-camber of the tie beam and arch rib based on the deformation data.

This invention relates to the fields of building information modeling (BIM) and digital twin technology, specifically a building lifecycle management system based on digital twins, comprising: an ideal benchmark reconstruction unit: fusing BIM and real-time meteorological environmental data to perform finite element calculations to generate a dynamic ideal field benchmark; a defect parameter injection unit: extracting disturbance operators and superimposing them onto the BIM to generate a theoretically damaged simulation state; a dual-track difference extraction unit: extracting the real residual tensor from the difference between the real-time sampling stream and the dynamic ideal benchmark, and extracting the theoretical residual tensor from the difference between the simulation state and the dynamic ideal benchmark; a coupled verification and decision unit: calculating the similarity comparison threshold and outputting the structural defect tracing results; and a dynamic adaptive feedback unit: updating the disturbance operators and adjusting the sampling frequency. This invention removes environmental noise, reveals the characteristics of weak structural defects, and reduces false alarms and missed alarms under extreme weather conditions.

This invention relates to the field of ship design technology and discloses a rudder system optimization design method based on nonprobabilistic reliability theory, comprising the following steps: S1: Determine the mechanical performance design values ​​of key components of the rudder system based on nonprobabilistic reliability indices, conduct parameter sensitivity analysis to determine the sensitive variables affecting the rudder stock torque, construct a parameterized model library, and generate a sample space through automated simulation scripts; S2: Call the parameterized model library to generate a three-dimensional model, perform finite element calculations of the rudder-propeller combination, simulate the hydrodynamic performance of the rudder system under different rudder angle conditions, and compare and analyze the results with reference data and standard calculations. By integrating nonprobabilistic reliability theory and comparing nonprobabilistic reliability indices and convex set models, parameter uncertainties are effectively handled, the reliability of the rudder system design is improved, and the optimization ideas of portal frame structures are used to reduce design constraints and improve efficiency.

The invention belongs to the technical field of high-frequency transformer simulation, and discloses a high-frequency transformer electric field, magnetic field, temperature field and force field analysis method and simulation device. Comprising the steps of obtaining a high-frequency transformer electromagnetic structure and establishing a three-dimensional high-frequency transformer prototype model; segmenting the three-dimensional high-frequency transformer prototype model into basic units and determining information of each basic unit; performing calculation based on the basic unit information to obtain static field and magnetic field finite element calculation results of the high-frequency transformer; calculating to obtain a temperature-fluid field and force field finite element calculation result of the high-frequency transformer; and setting boundary conditions of a temperature field and a force field based on finite element calculation results of the temperature-fluid field and the force field of the high-frequency transformer, and carrying out iterative solution on the electromagnetic-thermal-fluid-force field by using a solver to obtain distribution of an electric field, a magnetic field, the temperature field and the force field of the whole high-frequency transformer. Reference is provided for calculation of the electric field, the magnetic field, the temperature field and the force field of the high-frequency transformer.

The application discloses a near-field dynamics-finite element coupling method and system, relates to the technical field of quasi-brittle material failure prediction and mechanical numerical simulation, and comprises the following steps: the method is simple to calculate, a finite element method is completely used in a structure solving process, a near-field dynamics-finite element coupling region is used as a "submodel" and does not directly participate in calculation; displacement calculated by the finite element method is applied as a boundary condition on the boundary of the coupling region, and near-field dynamics model calculation is carried out; when a crack appears in the near-field dynamics model, element deletion is carried out on the finite element unit according to the length of the crack, so that the structural stiffness decline caused by crack propagation is realized. The coupling model can predict the damage of brittle materials, simulate spontaneous initiation and propagation of cracks, and compared with a pure near-field dynamics model, the coupling model can greatly improve the calculation efficiency.

The application discloses a rotor modification-based permanent magnet motor vibration noise suppression method, which comprises the following steps: creating a permanent magnet built-in rotor modification slot parameterized finite element model; adjusting the range of modification slot parameters to obtain a plurality of rotor modification slot parameterized geometric models; automatically generating parameterized rotor models under different modification slot parameter combinations by using an automatic program and finite element software, and performing stress distribution calculation under rated speed and peak speed working conditions; for the model meeting the structural strength, determining the first modification slot size based on electromagnetic finite element calculation of air gap node electromagnetic force distribution under the no-load working condition of the motor; further determining the second modification slot size based on electromagnetic finite element calculation of air gap node electromagnetic force distribution under the load working condition of the motor; and verifying the vibration noise of the optimal rotor modification slot scheme based on acoustic simulation software. The method can effectively improve the air gap magnetic flux waveform and reduce the radial electromagnetic force wave, and realizes the low noise of the motor under multi-working condition operation.