11 results about "Infinite element" patented technology

The invention discloses a construction method of an anchoring anchor rod crack defect guided wave detection numerical model, and belongs to the field of anchor rod nondestructive detection.According to the constructed numerical model, finite element-infinite element coupling is adopted for optimizing the surrounding rock stratum boundary, the problem of boundary multi-reflection echoes caused by artificial boundary truncation is solved, and the detection accuracy is improved. The workload of overall grid division is reduced; the method improves the calculation efficiency while guaranteeing the propagation precision, and effectively simulates the guided wave propagation behavior in the infinite boundary of the surrounding rock stratum. The numerical model constructed by the method is used for detecting the crack of the anchor rod under different defect degrees, so that the defect echo amplitude is in an ascending trend along with the increase of the defect degrees, and the bottom echo amplitude is in a descending trend along with the increase of the defect degrees. The numerical model constructed by the method positions the defect position of the anchor rod crack under different defect degrees, the result shows that the change of the defect degree basically does not influence the positioning of the defect position, the defect position can be accurately positioned through the one-way defect echo and the bottom echo, and the error range is less than or equal to 3%.

The invention discloses a pile-soil coupling loss prediction method based on soil layer quantification and a neural network. The method comprises the following steps: firstly, through parameterized finite element-infinite element coupling numerical simulation, extracting a pile-soil coupling loss quantitative index-transfer function amplitude ratio; converting the multi-layer soil body distribution information into standardized soil layer distribution characteristic parameters through a normalized coordinate system; then, a neural network model is constructed, pile body parameters, load parameters, characteristic frequency points and soil layer distribution characteristic parameters serve as input, and a transfer function amplitude ratio serves as an output target for training; and finally, rapid and accurate prediction of the pile-soil coupling loss is realized through the trained model. According to the method, effective quantification of complex soil layer space distribution is innovatively realized, and the problems of insufficient precision and low efficiency of a traditional method in pile-soil dynamic coupling loss prediction are solved.

The invention relates to the field of acoustic nondestructive testing, and provides a rapid analysis method, device and equipment for machining defects of remanufactured parts, and the method comprises the following steps: establishing a finite element simulation model of a part to be analyzed; meshing the finite element simulation model into a finite element mesh and an infinite element mesh; applying a preset ultrasonic excitation signal to the excitation point; calculating the propagation process of the ultrasonic excitation signal in the to-be-analyzed part through a finite element simulation model, and collecting an ultrasonic echo signal at a signal collection point; extracting a plurality of characteristic parameters related to defect states from the collected ultrasonic echo signals; and inputting the plurality of extracted feature parameters into a pre-trained deep learning prediction model to obtain a residual service duration prediction result of the to-be-analyzed part. According to the method, the problem of insufficient ultrasonic detection accuracy in the prior art is solved, and the residual service time of the remanufactured part is quickly and accurately predicted.

The invention discloses a lateral logging forward modeling simulation method and system based on finite element and infinite element coupling, and relates to the technical field of geophysical logging, the method comprises the following steps: establishing a two-dimensional lateral logging forward modeling model corresponding to an axisymmetric anisotropic stratum, carrying out grid division, and carrying out finite element calculation outside a finite element calculation area of the two-dimensional lateral logging forward modeling model; arranging a mapping infinite element as a boundary unit; calculating a total stiffness matrix; according to the total stiffness matrix, applying an equipotential boundary condition to each metal electrode of the logging instrument on a node in the two-dimensional lateral logging forward modeling model; and solving the two-dimensional lateral logging forward model after the equipotential boundary condition is applied to obtain each sub-field which is sequentially and independently emitted by each emission electrode, and synthesizing and focusing all the sub-fields to obtain lateral logging response. According to the method, the mapping infinite element is adopted as the boundary unit, the boundary unit is coupled with the finite element calculation area, and forward modeling of lateral logging can be rapidly and accurately achieved.

The invention discloses an earthquake response modeling and analysis method for a deep underground chamber structure. The method comprises the following steps: firstly, constructing a finite element and infinite element coupled three-dimensional calculation model; then, a mapping relation between the initial crustal stress data and stress field parameters is constructed, the stress field parameters are assigned to a three-dimensional calculation model, and the initial stress field parameters are iteratively corrected by applying pressure to the model; then, converting the seismic load into an equivalent acceleration load, applying the equivalent acceleration load to the boundary of the bottom of the model, and continuously spreading the equivalent acceleration load between near-field and far-field rock masses; and finally, earthquake response calculation is carried out, the displacement, stress distribution, acceleration response and development process of the chamber structure under the earthquake action are simulated, and key indexes are extracted to analyze the response rules of the chamber structure under different earthquake intensities and different burial depths. According to the method, the refinement of the model and the high efficiency of calculation are both considered, the error of cross-software operation is reduced, the working efficiency is improved, and a direct numerical basis can be provided for the aseismic design of the deeply-buried underground chamber structure.

The invention discloses a PDC drill bit shaft bottom in-situ rock breaking debris particle size measurement method and system, and relates to the technical field of shaft bottom in-situ rock breaking debris particle size measurement, and the method comprises the steps: constructing a shaft bottom in-situ finite-discrete-infinite element rock model; the in-situ stratum rock at the well bottom is regarded as an infinite boundary, and PDC tooth cutting rock breaking parameter calibration and PDC tooth rock breaking model modeling are carried out; and under the non-bilinear damage criterion, through the interaction of the in-situ finite-discrete-infinite element rock model and the PDC tooth crushing rock model, the in-situ initial rock debris particle size of the well bottom is measured, and the performance of the drilling fluid is adjusted. According to the method, the well bottom in-situ rock debris particle size is measured based on the non-bilinear damage criterion of the typical rock stress-strain curve and the well bottom in-situ finite-discrete-infinite element rock model in a coupling mode, and the reliability and accuracy of well bottom in-situ rock breaking rock debris particle size measurement are improved; and the problem of high calculation cost or sound wave effect of a finite-discrete element model is avoided.

The application discloses a high-fidelity simulation method for a magnetron sputtering cathode magnetic field based on finite element analysis, and belongs to the technical field of magnetic field simulation. The method comprises the following steps: constructing a geometric model of a magnetron sputtering cathode magnet system in a target space, and setting an analysis domain for solving in the geometric model; at least one geometric layer surrounding the analysis domain is set outside the analysis domain, and the geometric layer is explicitly defined as an infinite element domain in finite element analysis software; a structured sweep grid is applied in the infinite element domain along a coordinate stretching direction; the sweep direction of the sweep grid is consistent with the far-field decay direction of the magnetic field; a grid is applied to the analysis domain, and a static magnetic field control equation is solved to obtain the magnetic field distribution on and near the surface of a cathode target material. The above scheme improves the overall calculation efficiency while ensuring the simulation accuracy.

The invention discloses a complex site seismic oscillation input method, which comprises the following steps of: firstly, constructing a three-dimensional complex site finite element model, modifying a finite element boundary of the three-dimensional complex site finite element model into an infinite element artificial boundary, and constructing to obtain a three-dimensional complex site finite element-infinite element coupling model; then calculating to obtain an equivalent node load of any node on the regular boundary surface of the infinite element artificial boundary by combining a seismic wave acceleration time travel curve and a seismic wave incident angle, and taking the equivalent node load as seismic oscillation input of the regular boundary of the complex site; and finally, constructing a large-size model, and calculating according to the large-size model to obtain an equivalent node load of any node on the irregular boundary surface of the complex site, and taking the equivalent node load as seismic oscillation input of the irregular boundary of the complex site. According to the method, the seismic oscillation input of the regular boundary and the irregular boundary is deduced and calculated, so that the seismic oscillation input of the complex site is completed, the seismic response analysis of the complex site is realized, and a reference is provided for the anti-seismic safety evaluation of the complex site.

This invention discloses a method for analyzing the dynamic response of deep-sea pile driving soil based on ALE fluid-structure interaction and infinite element boundary, belonging to the field of marine engineering technology. It solves the technical problem of mesh distortion and hourglassing caused by severe soil compression at the pile tip during deep penetration. The key to this technical solution is the introduction of an adaptive mesh technique with an arbitrary Lagrange-Eulerian adaptive mesh control domain. By dynamically refactoring the mesh topology during the analysis step, mesh distortion and hourglassing caused by severe soil compression at the pile tip during deep penetration are effectively avoided, enabling the finite element model to stably simulate the penetration depth process.

The invention discloses a far-field noise simulation prediction model for a single-stage axial flow compressor component of a turboshaft engine, relates to the technical field of engine noise prediction, and aims at solving the problems that a traditional noise prediction method is large in computing resource consumption and limited in simulation precision. The far-field noise simulation prediction model comprises a geometric modeling module used for constructing a geometric model; the flow field calculation module is used for constructing a flow field calculation model; the flow field solving module is used for executing steady-state flow field steady solution and transient flow field unsteady solution; the acoustic calculation module is used for constructing an acoustic calculation model, and the sound source mapping module is used for selecting a large turbulence energy area in a flow field as a Lightthill body sound source and mapping flow field data to the sound source; and the sound propagation calculation module is configured to set a gas compressor fluid domain as a finite element grid area, and an infinite element two-dimensional surface grid unit is arranged at the outlet boundary so as to calculate the sound pressure level frequency spectrum of the far-field monitoring point. According to the method, on the premise that the precision is guaranteed, efficient prediction of the far-field noise of the gas compressor is achieved with low cost.

The application relates to the technical field of geotechnical engineering anti-seismic analysis, in particular to a three-dimensional layered ground seismic vibration input method based on an infinite element artificial boundary, which comprises the following steps: solving a three-dimensional layered ground seismic equivalent node force expression considering the infinite element artificial boundary under a free field; establishing a three-dimensional layered ground model mixed with infinite elements and finite elements, obtaining the numbering, spatial coordinates and equivalent node area of each boundary node at the boundary of the finite domain, and calculating the ground stress field node force matched with the initial stress field; calculating the seismic equivalent node force of the grid node at the junction of the infinite and finite grids, batch modifying the layered ground model calculation file, and realizing the initial static force and seismic force input of each boundary node. The seismic vibration equivalent node force obtained by the application has high precision, conforms to the propagation characteristics of the seismic wave in the layered ground, and realizes batch application of the seismic node force of the heterogeneous ground, and has simplicity and operability.