203 results about "Contact model" patented technology

The invention relates to a buried end cable wear prediction method and system based on multi-physics field coupling simulation, and belongs to the field of cable wear prediction. The method comprises the following steps: collecting and preprocessing hydrological environment data; carrying out three-dimensional ocean flow field modeling and fluid-solid coupling analysis; cable dynamic response simulation; cable and support structure contact modeling: applying the dynamic response of the cable to modeling of a contact area, and establishing a time-varying contact model by adopting an improved Hertz contact theory; abrasion loss calculation, wherein a dynamic Archard abrasion model is adopted to calculate the local abrasion volume; and fusing and visualizing multi-physics field data. Through a Navier-Stokes equation and a fluid-structure interaction algorithm, ocean current dynamic pressure, shear stress and cable mechanical response are interacted in real time, and the defect that a traditional static load model ignores fluid-structure bidirectional coupling is overcome; an improved Hertz contact model is adopted, the contact radius and the slip speed are introduced, and the over-underestimation problem of a traditional static contact hypothesis on abrasion loss prediction is solved.

The invention relates to a rigid-flexible trans-mass self-adaptive robot force position and rigidity collaborative optimization method and system, and relates to the technical field of robot control, and the method comprises the steps: firstly, carrying out the linearization processing of a robot dynamic model through a semi-implicit integral method, and obtaining a robot dynamic model; and in combination with an extended Kalman filter, stiffness parameters in the contact operation process are estimated in real time, a dynamic stiffness sensing model is constructed, and the system response capability is effectively improved. Then, a rigidity parameter is embedded into a Hertz contact model, the dependence of a traditional model on prior information of a contact surface is broken through, a dynamic interaction model between the robot and an operation object is established, and high-precision real-time sensing of normal force and friction force is achieved. And finally, under a nonlinear model predictive control framework, multi-dimensional physical constraints are constructed based on the contact force, the position and the contact rigidity, an optimal control model is obtained, control input is dynamically and adaptively updated through rolling optimization, and the stability and the control precision of the robot in rigid-flexible heterogeneous contact operation are improved.

The present invention belongs to the field of mechanical engineering, and particularly relates to an equivalent model of a knocking kinematic pair of a continuous elastic body and a modeling method thereof. An equivalent model is established for the knocking kinematic pair in a continuous elastic body mechanical structure or system, that is, the non-linear mapping relationship between the knocking pulse force and the knocking initial velocity. By assuming that the knocking force pulse is a half-cycle sine wave, and simultaneously using the Hertz contact model and the origin transfer function or impulse response function of the mechanical structure at the knocking contact point to express the contact mechanical properties of the knocking pair material pair and the impedance properties of the mechanical structure at the knocking part, the relationship between the output and input of the non-linear equivalent model, that is, the knocking pulse force and the knocking initial velocity, is derived. Through the method of the present invention, the problem of rapid prediction of the knocking force pulse of a continuous elastic body mechanical structure can be solved.

The invention discloses a three-dimensional fluid-solid coupling simulation method and device for a rod falling behavior of a control rod drive line, and relates to the technical field of simulation of the rod falling behavior of the control rod drive line. Fluid boundary updating in the rod falling process of the control rod is processed through a structural grid and dynamic grid layer laying technology on the basis of computational fluid dynamics and multi-body dynamics theories; a modal synthesis method and a Hertz contact model are adopted to solve the problems of flexibility and contact friction of a large-length-diameter-ratio moving part, key factors including fluid resistance and mechanical friction resistance influencing rod falling simulation accuracy are calculated, fluid-solid coupling is achieved through one-way data transmission, three-dimensional fluid-solid coupling of the rod falling behavior of the control rod drive wire is achieved, and the control rod drive wire rod falling simulation accuracy is improved. The accuracy of a simulation result is improved, the degree of dependence on a prototype test is reduced, and a technical basis is provided for researching the rod falling behavior of the reactor control rod drive wire.

A nuclear main pump double-cone sealing leakage detection method based on a bolt load and a sealing contact model relates to the technical field of double-cone sealing leakage detection.The method comprises the steps that firstly, the bolt load is substituted into a mapping model of the bolt load and gasket sealing surface contact pressure, and the sealing surface contact pressure is obtained; dividing calculation units for the sealing contact surface, and completing the construction of a gasket sealing rough contact surface model of a single calculation unit; a finite element simulation method is used for obtaining a sealing contact surface entity after compression deformation; the deformed sealing contact surface entity is subjected to micro fluid leakage calculation in Fluent fluid simulation software, and the leakage rate of a single calculation unit is obtained; finally, the leakage rate of the whole double-cone sealing structure is obtained according to division of the calculation units. By acquiring the king bolt load and the sealing contact model, tiny leakage detection of the double-cone sealing structure is achieved, and the method has the advantages of being high in accuracy, simple in test, high in environmental adaptability and the like.

The invention discloses an aggregate random distribution concrete PFC (Power Factor Correction) simulation method, which comprises the following steps: a model selection step: determining a parallel bonding model as a mechanical model for concrete material simulation; a cement mortar matrix generation step of generating a cement mortar matrix by using particles in a set size range in a set space range based on the model, and setting pore density, particle density and contact model parameters; a coarse aggregate random distribution simulation step: randomly covering and grouping original particles in the matrix in a grouping and range mode; a concrete numerical model construction step: determining particle classification so as to distinguish cement mortar and coarse aggregate; and a model reliability verification step: comparing indoor test results through a uniaxial compression test. According to the method, the simulation accuracy is improved, the randomness of aggregate is reduced, the model reliability is ensured, the matrix simulation refinement degree is improved, and a method is provided for concrete modeling and performance research.

The invention relates to a dynamic characteristic modeling method and system for an alternating impact disassembling operation robot, and relates to the technical field of robot control, and the method comprises the steps: firstly, comprehensively considering the dynamic characteristics of a robot joint side and a motor side, building a torque-driven flexible joint dynamic model, and determining the influence of joint flexibility on impact response; secondly, estimating normal impact force and tangential friction force by adopting an exponential inelastic continuous contact model, constructing an alternating impact dynamic model, and quantifying momentum change and a nonlinear dynamic effect in the impact process; and finally, a multi-space dynamic characteristic coupling model is established, the interaction mechanism of the joint space, the impact contact space and the task space is systematically analyzed, the accurate speed after impact is output, an impact force control strategy is generated, the dynamic response precision of the robot under the alternating impact operation is improved, the active utilization of the robot on the impact effect is achieved, and the reliability of the robot is improved. And the stability, the accuracy and the high efficiency of the disassembling operation are ensured.

The invention belongs to the technical field of crossing of artificial intelligence and computational mechanics, and particularly relates to an artificial intelligence-based MPM simulation method and system for a mold bag sand cofferdam, a three-dimensional simulation system of the mold bag sand cofferdam is constructed in combination with an MPM method, and the penetration state of sand and geotechnical cloth is detected in an accelerated manner by utilizing a penetration tracking algorithm and spatial Hash. An artificial intelligence algorithm is introduced, a reward function is designed with minimum penetration depth and penetration times as targets, penetration prediction of MPM particles is driven, the speed and stress of the MPM particles are further dynamically regulated and controlled on the basis of a predicted contact model and the artificial intelligence algorithm, penetration is prevented, numerical stability is ensured, and the prediction accuracy of the MPM particles is improved. The calculation precision is improved by adopting implicit integration and gradient descent methods; and bidirectional coupling of the sand and the geotechnical cloth is realized through a visualization module. The problems that in a traditional method, coupling simulation of sandy soil and a flexible structure is low in efficiency, easy to penetrate, unstable in numerical value and the like are solved, and the accuracy and reliability of simulation analysis of the mold bag sand cofferdam structure under the complex working condition are remarkably improved.

Provided are a method and apparatus for calibrating contact parameters of electrode materials, and a computer storage medium. The method includes the following operations. A discrete element simulation test is performed on an electrode material based on a calibration model and calibration ranges of contact parameters of the electrode material when an axial force-displacement curve of a target pellet of the electrode material meets an adaption condition of the contact model; then a simulated axial pressure-axial strain relationship of the electrode material is acquired based on a target discrete element simulation parameter of the electrode material; whether the contact parameters are calibrated successfully is judged based on this relationship; and when the contact parameters are calibrated successfully, calibration results of the contact parameters are determined.

The invention provides a root-soil mixture impact penetration sounding dynamic response prediction method. The method comprises the following steps: firstly, constructing a discrete element model of a root-soil mixture, and constructing a root system structure with high simulation characteristics in the discrete element model; and fine simulation of interaction of the root system and the soil particles under the impact penetration power load is realized in combination with a contact model for simulating mechanical properties of the root-soil mixture, so that impact penetration penetration prediction of the root-soil mixture is finally realized. According to the method, various behaviors such as contact, friction, stripping and tearing between root-soil particles can be dynamically simulated on a microcosmic level, the behaviors are coupled into an integral model of impact penetration sounding, and the penetration resistance mechanism of a root-soil mixed medium can be accurately captured through the method, so that the penetration resistance of the root-soil mixed medium is accurately determined. And a reference is provided for abnormal identification and correction of the penetration signal.

The invention discloses a simulation method for inherent microfractures in rock based on a discrete element method, which comprises the following steps of: constructing a discrete element numerical model sample, performing static equilibrium calculation on the sample by adopting a linear model, applying fixed confining pressure to an initial sample, and performing servo calculation; a Flat-joint contact model is added, and contact bonding mesoscopic parameters are set for static balance calculation; modifying bonding contact into non-bonding contact, adding a contact gap and performing static balance calculation; carrying out a loading test; processing a test result to obtain mechanical parameters of the sample, comparing the mechanical parameters of the numerical model test with the mechanical parameters of the rock sample obtained by the indoor test, if the two mechanical parameters are matched, outputting the result, and terminating the simulation process, otherwise, modifying the contact bonding mesoscopic parameters. And reloading the test until the mechanical parameters of the numerical test are matched with the mechanical parameters of the indoor test. According to the method, the inherent micro-fracture in the rock is simulated, and the defects of a conventional model in a discrete element method are overcome.

The invention discloses straight fluted tap tapping based on an oblique angle cutting model, and relates to a straight fluted tap mechanical modeling and torque prediction method. The method aims at solving the problems that in the tapping process of the straight fluted tap, the cutting torque time is too long, and the precision of a calculation result is low. The method comprises the following steps: step 1, establishing a straight fluted tap tapping bevel angle cutting model; 2, establishing a straight fluted tap cutting edge mechanical model; 3, establishing a workpiece geometric model; 4, calculating a unit mechanical model according to the step 2 and the step 3; 5, performing overall mechanical model calculation according to the tool and workpiece contact mechanical model; and 6, finite element simulation of the tool and workpiece contact model is carried out. Through comparison of a simulation result and a calculation result, the accuracy of the method is verified. Through comparison with simulation time of a single linear model, high efficiency of the torque prediction method based on the bevel angle cutting model is verified. The method is applied to the field of tapping manufacturing.

The invention discloses a gas turbine pull rod rotor wheel disc vibration analysis method, system and device, and relates to the technical field of gas turbines.The method comprises the steps that a three-dimensional finite element kinetic equation of a rotating part is constructed; the contact stiffness of adjacent contact units is deduced by considering the rough contact characteristic of the contact interface and combining a microscopic contact mechanical model of the contact interface and a rough consolidation interface contact mechanical model based on the statistical theory; a stress strengthening effect is considered, and a stress stiffness matrix and a contact stiffness matrix are iteratively calculated; a central pull rod end face tooth structure considering local contact nonlinearity is constructed, and an end face tooth contact model considering collision separation is constructed; carrying out vibration response solution on the three-dimensional finite element kinetic equation by adopting a degree-of-freedom reduction method; according to the method, the vibration analysis model is established, the pull rod rotor does not need to be simplified, and geometric features, contact surface features and load effects of an original model can be reserved to a great extent.

The invention belongs to the field of geologic disaster prevention and control of geotechnical engineering, and provides a multi-scale numerical simulation method for a slope instability mechanism of a ductile shear zone, which comprises the following steps: acquiring physical and mechanical parameters of a rock-soil body material, and establishing a numerical model based on a particle flow discrete element method; a Johnson-Kendall-Robert contact model is adopted as a contact model between particles, the contact force between the particles is calculated, and meanwhile, a pressure interference parameter is defined to control the limit value of normal contact rigidity; performing dynamic modeling of the discrete element particle system based on a particle generator; static modeling of a discrete element particle system is carried out based on a Lagrange body continuous unit component; the acting force of discrete element particles is converted into equivalent grid node force through an equivalent node force conversion method, and surface attributes of all unit sets possibly involved in contact are defined in a solver.

The invention discloses a flexible biological and interception model construction method based on particle contact and a simulation device, and the method comprises the steps: carrying out the improved contact model parameter determination based on various parameters of a marine organism according to a discrete element particle contact model of a target marine organism; and the flexible contact model is combined with the particle replacement model to generate a flexible target marine organism discrete element model, a target marine organism group is constructed, and a finite element / discrete element coupling calculation method is utilized to perform simulation evaluation on the interception efficiency of the interception net on the target marine organisms. The discrete element particle contact model combines the characteristics of efficient calculation of discrete elements and flexibility of biological materials, can accurately and quickly simulate and obtain the results of deformation, breakage, escape and the like of marine organisms under the action of the blocking net, and analyzes the interaction mechanism of the blocking net and the marine organisms according to the results. According to the method, the blank of describing the biological material by discrete elements can be filled, and the research on the marine organism intercepting mechanism of the intercepting net is facilitated.

The invention discloses a simulation analysis method of flexible particles based on a bonding combination hyper-ellipsoid model. The simulation analysis method comprises the following steps: determining shapes, sizes, positions, numbers and material attributes of first-level sub-particles forming the flexible particles according to real flexible particles; determining the shape, the size, the position and the number of second-level sub-particles forming each first-level sub-particle, and constructing the first-level sub-particles through a hyper-ellipsoid model; according to the determined position and material attribute of the first-level sub-particle, setting a bonding bond model for the contact model of the material attribute of the adjacent first-level sub-particle; corresponding coordinate positions, rotation angles and material attributes are given to the first-level sub-particles, and the first-level sub-particles are combined to form a bonding combination hyper-ellipsoid model of the flexible particles; and applying the bonded combined hyper-ellipsoid model to a flexible particle system in a discrete unit analogue simulation industrial process to obtain a simulation result. According to the simulation method, accurate modeling of the flexible particles is achieved, the motion law of the flexible particles is obtained, and the authenticity of the simulation result of the flexible particle system is improved.

The invention discloses an involute helical gear forming grinding force prediction method, which comprises the following steps: firstly, based on a helical gear forming grinding space motion relationship, establishing a helical tooth surface model comprising an involute surface and a tooth root transition curved surface, and constructing a geometric contact model of a grinding wheel and a gear; then, tooth surface deformation data obtained after heat treatment are obtained through a three-coordinate measuring machine, coordinate mapping is carried out, and the grinding depth and contact parameters are corrected; on the basis, a grinding force integral model considering the heat treatment influence is established by combining a plane grinding mechanism, and integral calculation is carried out on tangential and normal grinding force of a tooth surface involute section, a transition arc section and a tooth bottom section; finally, actual measurement data are obtained through a grinding experiment, and model parameter calibration is completed. According to the method, dynamic and accurate prediction of tangential and normal grinding force in the bevel gear forming and grinding process can be achieved, and a reliable basis is provided for mechanical behavior analysis and process optimization in the gear machining process.

The invention discloses an efficient identification method for connection rigidity of a steel pipe pole of a power transmission line, which relates to the field of structural health monitoring, and comprises the following steps: constructing a multi-scale finite element model of the steel pipe pole, acquiring displacement and frequency response of the structure to carry out parameter sensitivity analysis, and screening key correction parameters; constructing a key parameter-structure response sample data set, and training and optimizing an FEA-Net neural network model; and constructing a Bayesian correction framework, solving posterior probability distribution by adopting a TMCMC algorithm, and realizing the probabilistic identification of the connection stiffness and the systematic correction of the finite element model. By constructing a local refined contact model, a bolt pretightening force-connection rigidity corresponding relation is established, and an effective means is provided for verifying whether the rigidity of the corrected model is matched with the rigidity of an actual structure or not. The structure rigidity damage position can be accurately recognized, the rigidity degradation degree can be quantified, and a high-credibility model basis is provided for safety evaluation, digital twinborn construction and operation and maintenance decision making of engineering structures such as electric transmission line steel pipe poles and the like.

The invention relates to the technical field of optical machining, in particular to a polishing surface roughness prediction method based on a robot flexible ball head tool, which comprises the following steps: firstly, establishing a microscopic contact model of the flexible ball head tool and a workpiece, and determining first pressure distribution of a contact area between the flexible ball head tool and the workpiece; vibration of the flexible ball head tool is converted into pressure fluctuation of the flexible ball head tool, total pressure distribution during machining is obtained, and then second pressure distribution is formed; in combination with the second pressure distribution and the relative speed model during machining of the flexible ball head tool, a material removal rate model during machining of the flexible ball head tool is obtained; performing path integration on the material removal rate model to obtain the surface height change of the workpiece in the machining process; and the surface roughness of the machined workpiece is obtained by combining the original surface height and the surface height change of the workpiece. According to the method, the quantitative relation between the vibration parameters and the surface roughness is disclosed, and a theoretical basis is provided for optimizing polishing process parameters and controlling the surface quality.

This invention discloses a method for calculating the contact magnetoelectric coupling variables of a piezoelectric matrix containing piezoelectric magnetic particles. This method, which pertains to the field of novel contact applications for magnetoelectric functional devices, includes a general model for achieving the functional properties of MEE composite materials through contact loading. Using a contact model of a MEE composite material containing piezoelectric magnetic particles in a piezoelectric matrix as an example, the method employs finite element numerical simulation based on the constitutive models of the piezomagnetic and piezoelectric phases and multi-physics field coupling theory to systematically reveal the mechanism by which the magnetoelectric coupling variables are controlled by force loading.

The application discloses a short-fiber reinforced ablative material bulk ablation simulation method, and belongs to the technical field of multifunctional composite materials and structure numerical simulation.The application comprises the following steps: constructing a discrete system composed of a series of spherical particle units by using a discrete element method; calculating the contact area, contact force and connecting force of the particle units by using a Hertz-Mindlin contact model and a parallel-bond model at each calculation time step; calculating the temperature of the particle units by using an energy conservation principle and a Fourier heat conduction law; calculating the displacement and angular displacement of the particle units by continuously integrating the momentum conservation equation twice; updating the velocity, displacement and diameter of each particle unit, and updating the porosity and pore pressure of the discrete system; iteratively solving and visualizing until a specific condition is met, and ending the simulation.The application characterizes the internal structure features of the short-fiber reinforced ablative material by using the discrete element method, so that the numerical simulation accuracy of the ablation process is improved, and the possibility of capturing the micro ablation mechanism is provided.

The application discloses a wheel fatigue life prediction method based on a rolling contact fatigue simulation technology, and comprises the following steps: establishing a finite element model of a wheel-axle-rail, performing grid encryption on a wheel-rail contact area, and performing static strength checking to obtain an initial finite element model meeting static force requirements; establishing a wheel-rail rolling contact model based on the initial finite element model, describing rolling motion of the wheel by using a hybrid Lagrangian / Eulerian description or a co-rotating coordinate system, and applying a wheel non-circularity excitation spectrum in explicit dynamics analysis to calculate a dynamic contact stress field under different axle loads and friction coefficients; and based on the dynamic contact stress field, a multi-axle fatigue damage model is used in combination with a linear cumulative damage criterion to calculate fatigue life, and an abrasion correction coefficient and a residual stress correction coefficient are introduced to correct the calculation results. The application significantly improves the prediction accuracy of fatigue defects such as wheel peeling, cracking and polygonization.

A method for constructing a dynamic model of a coupled system of high-speed railway train-track-substructure includes: experimentally obtaining key technical parameters with nonlinear and frequency-varying characteristics in the high-speed railway infrastructure system; constructing a novel wheel-rail contact model suitable for higher speed levels and integrating it into the vehicle-track coupled dynamic model; constructing a train vehicle model and track structure model based on the principles of multi-rigid-body dynamics and the finite element method; and using a self-developed program to realize the dynamic modeling of the train-track system; taking the ballastless track structure, subgrade, bridge, and tunnel structures of high-speed railways as research objects, and applying a finite element simulation platform to realize the construction of a refined finite element model of the track-substructure structure; this invention achieves a breakthrough in the theoretical modeling of the vehicle-track-substructure system of higher speed railways, providing a research method and platform for deepening the understanding of the coupled dynamic mechanism of complex systems of high-speed railway infrastructure with speeds of 400 km / h and above.

The application discloses a kind of discrete element modeling methods of multi-layer interpenetrating shear mixing drill and soil body, comprising: S1, the design parameter of multi-layer interpenetrating shear mixing drill is obtained, design parameter includes the pitch of blade, inclination, shape, size and quantity;Multi-layer interpenetrating shear mixing drill includes inner drill rod, multiple pairs of inner blades and outer frame arranged on inner drill rod;The outer frame includes multiple pairs of outer blades, two side plates and a collar arranged at intervals, and each pair of outer blades and each pair of inner blades are arranged at intervals;S2, the modeling of multi-layer interpenetrating shear mixing drill is carried out to obtain drill model;S3, establish soil model, import drill model, distribute contact model, and construct the coupling discrete element model between multi-layer interpenetrating shear mixing drill and soil particles;S4, simulation is carried out using coupling discrete element model, and quantitative analysis is carried out on mixing effect according to simulation result.The coupling discrete element model constructed by the above method has reliability and engineering applicability, and provides quantifiable basis for drill structure optimization.

The invention discloses a flexible wiping method and system of a flexible joint space robot based on dynamic adaptive impedance control, and the method comprises the steps: firstly, building a contact model between the flexible joint space robot and a wiped target; then, self-adaptive impedance control for dynamically updating impedance parameters is designed; and finally, performing comparison simulation on classical constant impedance, fixed update rate adaptive impedance control and dynamic update rate adaptive impedance control, and verifying the effectiveness of the method combining the dynamic update rate adaptive impedance control and singular perturbation control on friction force compliance control in the wiping process of the flexible joint space manipulator by a simulation result. The method is used for the field of on-orbit wiping of the flexible joint space robot, and accurate compliance force control can be conducted on the flexible joint space robot rapidly, efficiently and accurately; when the flexible joint space robot executes a task, necessary guarantee can be provided for the flexible joint space robot, and it is ensured that the space robot and a wiping target are not damaged, and meanwhile a good cleaning effect is obtained.

The invention discloses a gear pair meshing stiffness calculation method considering a thermoelastic coupling effect, which relates to the field of gear transmission, and comprises the following steps: establishing a gear temperature field model and a contact model by utilizing a finite element method, obtaining a gear heat conduction matrix and a structural stiffness matrix, and calculating to obtain gear meshing stiffness and tooth surface load distribution based on an actual tooth surface equation. Calculating tooth surface heat flux density based on tooth surface load distribution, tooth surface friction coefficient and relative sliding speed of each meshing position to obtain a gear thermal load matrix, calculating to obtain an equivalent node load matrix according to a gear heat conduction matrix and the thermal load matrix, and calculating to obtain tooth surface thermal deformation by combining the equivalent node load matrix with a gear structure stiffness matrix. And repeating the steps to obtain the meshing rigidity of the gear pair under the thermoelastic coupling effect. According to the method, the gear contact state iterative solution model based on the potential energy method, the matrix polycondensation method and the slicing thought is established, the requirement for computing equipment is lowered, and the solution efficiency is improved.

The present invention discloses a method for simulating the fluidity of a composite material filled with multi-particle diameter fillers. The method comprises: setting filler geometry information, and dividing unit grids according to the maximum filler particle size; determining filler physical property parameters and filler-filler, filler-wall contact models according to discrete element simulation, and defining a particle generator and model boundary conditions; using a particle diameter growth method to generate a random distribution structure of particles, and setting the initial velocity of the linear distribution of particles; determining a matrix material density and viscosity model, setting boundary conditions, and simulating the three-dimensional Couette flow of the matrix material at a given shear rate; using discrete element software to generate a dynamic link library file, and importing a coupling file; using computational fluid dynamics software to set coupling parameters, and importing a coupling file; combining computational fluid dynamics software with discrete element software for coupling calculation, and calculating the viscosity of the composite material. The present invention can more accurately and comprehensively analyze the viscosity variation law of composite materials filled with fillers of various shapes.

A method for stress concentration checking of the relief groove of the slewing bearing nose ring of an offshore crane, the method includes establishing a finite element model of the slewing bearing nose ring based on a computer, establishing a non-linear contact model, checking the contact strength of the nose ring mesh model, designing and checking the corner of the relief groove, and checking the fatigue strength of the corner of the relief groove; in application, by establishing a rolling element model, a nose ring model and a corner model of the relief groove, and discretizing them into meshes to generate a mesh discrete model of the slewing bearing nose ring, then loading the load to obtain the stress at the corner of the local relief groove, then establishing a non-linear contact model between the rolling element mesh model and the nose ring mesh model, solving to obtain the contact stress, and comparing the contact stress, the stress at the corner of the relief groove with the allowable stress, and finally performing a fatigue life simulation on the nose ring model to complete the checking work. Therefore, the present invention not only has a relatively concentrated and accurate evaluation result, but also has a relatively accurate calculation result.

The invention relates to a concrete structure fault movement damage simulation method based on damage contact constitutive, which belongs to the technical field of geotechnical engineering numerical simulation, and has the technical key points that the method is based on a plastic damage constitutive theory proposed by A.D.Jefferson and is combined with a discrete element method to simulate the fault movement damage of a concrete structure. A contact model suitable for cracking evolution of the concrete lining structure under the fault shearing condition is constructed; the method comprises the following steps: establishing a contact surface force-displacement increment relationship and a failure criterion by introducing parameters such as normal rigidity, tangential rigidity, tensile strength, cohesive force, a friction angle and fracture energy, carrying out secondary development coding based on a 3DEC development port by utilizing a C + + language, and generating a constructed DLL module file; by constructing a typical engineering numerical model, the development process of concrete cracks under fault movement is simulated, and sensitivity analysis is carried out. The method can accurately capture a structural damage path and a stress concentration part, and is suitable for engineering application scenes such as tunnel crossing fault and high-stress area support optimization.

The invention provides a method and system for improving the wheel-rail relation of a fixed frog based on rim groove depth design, and relates to the technical field of fixed frogs. The method comprises the steps that profile design data and wheel tread parameters of a wing rail-point rail of the fixed frog are obtained; according to the profile design data and the wheel tread parameters, wheel-rail contact traces are fitted, the wheel pair side roll angle is calculated through a minimum distance method, and contact geometric parameters are obtained; determining an initial optimization interval according to the contact geometric parameters and the limit value of the wheel-rail contact geometric relationship design index; processing the initial optimization interval based on a preset wheel set-frog rolling contact model to obtain a calculation result; and evaluating according to a calculation result to obtain a rim groove design scheme and a depth value. According to the method, the wheel-rail relation of the fixed frog area is systematically improved through collaborative design of the depth of the rim groove and the frog profile in combination with contact geometric analysis and multi-target dynamics optimization.