25 results about "Contact mechanics" patented technology

The invention discloses a cylindrical roller modification method based on a non-uniform rational B-spline curve, and relates to the technical field of bearing design. According to the method, a bearing contact mechanical model considering the roller modification effect is constructed, a modification contour is constructed based on a non-uniform rational B-spline curve (NURBS curve), an optimization model with the basic reference rated life of a bearing as a target function is established on the basis of meeting geometric constraint conditions, and an optimization algorithm is adopted for solving to obtain a final modification curve. The established contact mechanical model comprises a bearing static balance model and a roller-raceway contact mechanical model and is used for calculating load distribution and contact stress under the unbalance loading working condition. Compared with a traditional symmetrical logarithmic modification method, the problem that the axial stress of the roller is not uniform under unbalance loading can be effectively solved, the uniformity of contact stress distribution is improved, and the fatigue life of the bearing is prolonged.

The present application relates to the technical field of seepage mechanics, and particularly relates to a conical sealing surface leakage rate calculation method based on Darcy's law, comprising the following steps: a W-M function is used to simulate the random topography of the workpiece surface at a microscale, and a normalization method is used to generate surface point cloud data meeting roughness requirements; according to the surface point cloud data, a contact mechanics model is used to solve the change law between the contact state and the external load, and according to the Hertz contact theory, the contact between the rough surfaces is reconstructed as the contact between a rigid plane and a flexible rough surface; the surface is discretized into a three-dimensional grid model, the effective porosity is screened and calculated by using the connected domain discrimination method; a micro-leakage rate calculation method for the conical sealing surface in the flared pipe joint is obtained based on the effective porosity and the seepage mechanics theory algorithm; the leakage rate of the conical sealing interface is calculated, and the sealing performance of the interface is quantitatively evaluated. The present application improves the comprehensiveness and accuracy of the sealing performance evaluation.

This invention relates to a method for modeling the vibration of rolling bearings considering non-ideal Hertzian contact, belonging to the field of bearing vibration modeling technology, and includes the following steps: S1: Obtaining the basic geometric and material parameters of the rolling bearing; S2: Calculating the angular range of the load zone of the rolling bearing; S3: Calculating the geometric parameters of the contact between the rolling elements and the healthy raceway; S4: Calculating the mechanical parameters of the contact between the rolling elements and the healthy raceway; S5: Calculating the cage angular velocity parameters; S6: Calculating the angular position and angular velocity parameters of the rolling element's circumferential motion; S7: Calculating the deformation and contact force generated by all rolling elements in contact with the healthy raceway of the bearing; S8: Calculating the time-varying mechanical parameters implied by the contact between the rolling elements and the defect; S9: Dynamic modeling of the vibration excitation mechanism of the rolling bearing defect.

The application discloses a shield machine main drive sealing performance prediction method and device under actual complex service conditions, and relates to the field of mixed lubrication. The method takes a rotary lip seal as a research object, is based on a two-dimensional axisymmetric finite element model of a shield machine main drive rotary lip seal, and combines solid mechanics, lubricating oil film fluid mechanics, sealing lip surface micro-convex body contact mechanics, sealing lip surface normal and tangential elastic deformation, and thermodynamic analysis to quantitatively analyze data representing sealing performance of the shield machine main drive seal under actual complex service conditions, such as viscous friction and friction torque under different pressure differentials. The application can predict the sealing performance of the shield machine main drive seal under actual complex service conditions.

The application discloses a gas turbine pull rod rotor wheel disc vibration analysis method, system and device, relates to the technical field of gas turbines, and comprises the following steps: constructing a three-dimensional finite element dynamics equation of a rotating component; considering rough contact characteristics of a contact interface, combining a micro contact mechanics model of the contact interface and a rough consolidated interface contact mechanics model based on a statistical theory, and deducing contact stiffness of adjacent contact units; considering stress strengthening effects, iteratively calculating a stress stiffening matrix and a contact stiffness matrix; considering local contact nonlinearity of a center pull rod end surface tooth structure, constructing an end surface tooth contact model considering collision separation; and adopting a degree of freedom reduction method to solve vibration response of the three-dimensional finite element dynamics equation; and the method can greatly retain geometric characteristics, contact surface characteristics and load actions of an original model without simplifying the pull rod rotor by establishing a vibration analysis model.

The present application relates to concrete conveying technical field, especially to a kind of concrete self-slip conveying slow descending device design method, comprising: obtaining the real coarse aggregate sample of concrete to be conveyed and concrete mix proportion;Numerical modeling: the physical modeling of different types of slow descending device is carried out to obtain slow descending device numerical model;Based on the real coarse aggregate sample, construct coarse aggregate numerical model;Parameter calibration: the contact mechanics characteristic parameters between coarse aggregate, mortar particle and steel pipe wall are calibrated using physical experiment and numerical simulation combined calibration method;Slow descending device design: based on the contact mechanics characteristic parameters obtained by calibration and actual construction demand, the type of slow descending device is selected, and the parameters of slow descending device are determined, and the design of slow descending device is completed.The present application determines the best slow descending device type of concrete to be conveyed by comparing and analyzing the efficiency difference of different types of slow descending device, so as to adapt to the concrete conveying operation of hundred-meter high-fall condition, effectively control the balance of concrete segregation and pipe wall wear.

The invention discloses a cross-scale calculation method for contact pressure and contact area of a rough surface, and the method comprises the steps: constructing a contact stiffness model of a surface local region based on a microcosmic contact mechanics theory, and building a global weak form equation of a cross-scale contact problem according to a variational principle; secondly, establishing a discretization calculation model containing roughness contribution through a finite element method and a contact judgment criterion; and finally, a contact nonlinear iterative solution algorithm is established based on a Newton-Raphson algorithm and an improved Aikine acceleration method, and contact pressure distribution, a real contact area, a contact object displacement field and the like can be calculated. According to the method, the influence of surface microstructure parameters, contact object macroconfiguration and material parameters is considered, a conventional finite element method is expanded, contact cross-scale calculation between rough surfaces is realized, and theoretical and technical bases are provided for frictional wear, sealing analysis and the like of contact parts of a mechanical system.

The embodiment of the application provides a sealing surface contact analysis method, device and computer equipment, the method comprises the following steps: obtaining original surface information of a sealing surface pair to be analyzed; the sealing surface pair to be analyzed comprises a first rough surface and a second rough surface which are in pressure contact; obtaining equivalent surface information of an equivalent surface pair corresponding to the sealing surface pair to be analyzed according to the original surface information; the equivalent surface pair comprises an equivalent rough surface and a rigid plane; and performing contact analysis on the sealing surface pair to be analyzed according to the equivalent surface information. Since the actual contact area of the sealing surface pair to be analyzed and the equivalent surface pair is the same under the same external force, the contact mechanics analysis of the sealing surface to be analyzed can be performed according to the equivalent surface information, the stress contact condition of the sealing surface pair to be analyzed is obtained, the contact mechanics analysis process between the two rough surfaces is simplified, and the analysis efficiency is improved.

The invention discloses a dynamic thermal-mechanical contact stiffness prediction and digital twinning system and method based on a physical information hybrid neural network. Fractal elastic-plastic contact analysis, a physical information neural network and Transform time sequence prediction are fused. The method comprises the following steps: firstly, describing surface roughness and elastic-plastic deformation through a fractal model; then, PINN is used for embedding contact mechanics, heat conduction and an energy balance equation as physical constraints, so that the physical consistency of prediction is ensured; meanwhile, long-term time sequence dependence of load and temperature change is captured by adopting Transform; and finally, outputting a high-precision rigidity prediction value through adaptive weighted fusion. The system is deployed in an edge cloud collaborative digital twin architecture, and edge real-time low-delay reasoning and cloud continuous model optimization are realized. According to the method, the contact rigidity prediction precision, the adaptive capacity and the physical credibility under the dynamic working condition are remarkably improved, and an effective solution is provided for real-time state monitoring and intelligent compensation of a precise spindle-bearing system.

The invention discloses an explicit-implicit mechanism driven thermal performance analysis method for a coordinate grinding machine under multi-process conversion, and relates to the technical field of equipment thermal performance analys.The method comprises the steps that firstly, based on thermodynamic laws of heat conduction, heat convection and process intermittent heat shock, elastic mechanics and contact mechanics theories are combined; establishing an explicit thermodynamic mechanism equation of the key component of the grinding machine under multiple processes; carrying out multi-process actual measurement and simulation data iterative optimization, and carrying out symbolization, symmetry and dimensionless processing to obtain a multi-process unified explicit thermal differential control equation; with the deviation between theoretical prediction and actual measurement data as a target, an implicit mathematical expression is obtained through analysis; and finally, taking the implicit expression as a compensation item to be fused with the explicit equation, and carrying out iterative correction through an alternating optimization mechanism until the prediction precision of the thermal field reaches the standard. The method gives consideration to physical consistency and prediction precision, can accurately predict the complete thermal field distribution of the machine tool based on sparse thermal sensing data, and provides reliable theoretical support for guaranteeing the machining precision of the machine tool.

The invention discloses a strength detection tool and method for a composite cabin for an unmanned aerial vehicle. The detection tool comprises a cabin connecting plate, an end fixing device, a force application adjusting device and a deformation measuring structure. The force application adjusting device comprises a one-way stress application structure, a torsional stress application structure and a stress transmission structure. The stress transmission structure is provided with a special-shaped stress plate, a one-way stress transmission piece and a torsional stress transmission assembly. Particularly, a multi-linkage test structure is arranged, and conversion from torsional moment to radial one-way pressure is realized through geometric constraint and contact mechanics principles. According to the detection method, a step-by-step loading and multi-direction detection mode is adopted, initial detection, surface change detection and multi-direction comprehensive detection are achieved, and the preset deformation quantity is rapidly achieved through a displacement control mode by means of the qualified deformation quantity value detected last time. According to the invention, bending moment and torque load detection in four directions of 0 degree, 90 degrees, 180 degrees and 270 degrees can be completed through one-time clamping.

The application discloses a highway side slope compensation tensioning equipment slip clamp parameter calculation method, equivalent slip teeth are regarded as contact bodies acting on a working anchor; the contact between the slip teeth and the working anchor is equivalent to plane strain, and then a slip tooth-working anchor friction contact model is constructed; when the deformation energy of a metal material reaches the deformation energy required by metal material yielding, the metal material will yield or brittlely break; a slip tooth-yield strength model is constructed in this way; and the slip clamp with parameters meeting stress requirements is selected in combination with the need of an engineering safety factor. The method combines geotechnical engineering theory, Hertz contact mechanics theory, tribology and elastic-plastic mechanics theory to first provide a calculation method of a clamp of a highway side slope engineering prestressed anchor cable compensation tensioning equipment; the clamp material of the anchor cable compensation tensioning equipment is improved through calculation, the equipment range is improved, the anchor cable with a larger tonnage in the original design is applicable, the fatigue life of the slip clamp is increased, and the design parameters are optimized.

The application discloses a high-load roller bearing structure and material fatigue strength optimization and performance evaluation method, and relates to the technical field of bearing design and manufacturing. The method comprises the following steps: obtaining structure geometric parameters, heat treatment process parameters and chemical composition data of the bearing; calculating the hardening layer depth, surface hardness and residual stress distribution based on physical metallurgical rules; converting the microstructure features into the contact fatigue limit and stress correction factor; establishing a slice method contact mechanics model to solve the contact load distribution; taking the structure geometric parameters and heat treatment process parameters as double design variables, and taking the maximum fatigue life and the minimum heat treatment process cost as double objectives to construct a multi-objective optimization function; solving the Pareto optimal solution set by using a non-dominated sorting genetic algorithm; and evaluating the candidate schemes and generating an optimization report. The application solves the technical problem that the structure design and the heat treatment process are mutually separated and cannot be optimized in a cooperative manner in the prior art.

The invention relates to the technical field of computer-aided engineering, in particular to an asphalt pavement compression resistance analysis system based on dynamic simulation, which comprises a tire load discretization module used for performing contact mechanical pre-calculation and mapping to generate a grounding pressure distribution cloud picture according to three-dimensional scanning geometric data of a tire, and node pressure values in the grounding pressure distribution cloud picture are extracted, and the node pressure values are arranged according to the geometric features of the tire pattern. According to the method, the accumulation degree of internal damage of the material can be represented from the double dimensions of energy dissipation and shape distortion, the growth rate slope of a hysteretic loop geometric distortion index relative to the loading cycle number is monitored, the slope abrupt change coordinate is positioned, and the acute capture of the compressive fatigue life end inflection point is realized; the judgment logic based on evolution rate mutation is more accurate than pure stress threshold judgment, so that the reliability of prediction of the compressive fatigue life of the asphalt pavement structure is improved.

The invention relates to the technical field of concrete conveying, in particular to a design method of a concrete self-sliding conveying descent control device, which comprises the following steps: acquiring a real coarse aggregate sample and a concrete mix proportion of to-be-conveyed concrete; numerical modeling: performing physical modeling on different types of descent control devices to obtain numerical models of the descent control devices; constructing a coarse aggregate numerical model based on the real coarse aggregate sample; parameter calibration: calibrating contact mechanical characteristic parameters among the coarse aggregate, the mortar particles and the steel pipe wall by adopting a physical experiment and numerical simulation combined calibration method; and the descent control device is designed, specifically, the type of the descent control device is selected based on the contact mechanical characteristic parameters obtained through calibration and actual construction requirements, parameters of the descent control device are determined, and design of the descent control device is completed. The optimal descent control device type of the to-be-conveyed concrete is determined by comparing and analyzing the efficiency difference of different types of descent control devices, so that the method can adapt to concrete conveying operation under the hectometer-level high-fall working condition, and balance between concrete segregation and pipe wall abrasion is effectively controlled.

The invention relates to the field of pressure sensor design, and particularly discloses a pressure sensor microstructure design method based on hyperelastic contact mechanics, which comprises the following steps: fitting a plurality of hyperelastic constitutive models through a stress-strain curve obtained by an experiment, comparing the experiment and simulation results of hyperelastic micro-convex body contact, and selecting an optimal constitutive model; fitting an analytic solution of the superelastic micro-convex body contact, and verifying the applicability of the analytic solution to different superelastic micro-convex body contact problems; the structure forward design meeting the requirements of target sensitivity, pressure measurement range and linearity is realized; obtaining a sensitivity curve through an electric contact experiment, and verifying the feasibility of the design method; based on an application scene and material performance, a sensitivity upper limit which can be realized by the method is given. The method has an important engineering application value in the field of flexible electronics, and has the outstanding advantages that the microstructure parameters can be directly calculated according to the target performance requirements of the pressure sensor, and accurate mapping of'performance requirements-structure parameters' is realized.

The present application relates to the technical field of computer aided engineering, specifically to an asphalt pavement compression resistance analysis system based on dynamic simulation, which comprises a tire load discretization module, which is used to generate a contact mechanics pre-calculation and map a ground pressure distribution cloud map according to three-dimensional scanning geometric data of a tire, extract node pressure values in the ground pressure distribution cloud map, and arrange the node pressure values according to tire pattern geometric characteristics.In the present application, the cumulative degree of internal damage of materials can be characterized from the dual dimensions of energy dissipation and shape distortion, the growth rate slope of the hysteresis loop geometric distortion index relative to the number of loading cycles can be monitored, and the slope mutation coordinates can be located, thereby achieving sensitive capture of the compression fatigue life ending inflection point.This discrimination logic based on evolution rate mutation is more accurate than simple stress threshold determination, thereby improving the reliability of asphalt pavement structure compression fatigue life prediction.

The present application relates to the technical field of rolling bearing, in particular to a rolling bearing slip state analysis method considering raceway waviness, comprising the following steps: S1: establishing a waviness model of a wavy surface with time-varying curvature radius; S2: calculating time-varying displacement excitation based on contact geometry kinematics theory; S3: calculating time-varying stiffness based on Hertz contact theory and nonlinear characteristics of contact stiffness; S4: calculating displacement relationship and acting force of each bearing component; S5: calculating bearing nonlinear dynamics differential equation; S6: analyzing the influence of wavy amplitude and wavy order on slip through a bearing slip effect calculation method of time-varying displacement and time-varying stiffness coupling based on kinematics relationship, contact mechanics characteristics and multi-body dynamics; the present application provides a wavy bearing slip dynamics model based on time-varying displacement and time-varying stiffness coupling.

The invention provides a method and device for improving powder distribution compactness and efficiency of additive manufacturing powder, and relates to the technical field of additive manufacturing process optimization and computer simulation crossing. The method comprises the steps that a 3D printing equipment model is established and imported into EDEM software; the equipment model comprises structural parameters of a powder spreading mechanism, a scraper, a powder spreading bin and a powder supply bin, and physical attribute parameters of set powder particles, including particle size distribution, density, elastic modulus, Poisson's ratio and an inter-particle contact mechanical model. And the differences of the fine powder and the coarse powder in flowability and stacking compactness can be effectively considered. On one hand, the problems of fine powder agglomeration and dust raising are avoided, and the stability of powder distribution is improved; and on the other hand, the flow blocking phenomenon of coarse powder in the spreading process is improved, the surface of a powder bed is smoother, and the overall uniformity and density are remarkably improved.

The present application relates to the field of pressure sensor design, and specifically discloses a pressure sensor microstructure design method based on super-elastic contact mechanics, several super-elastic constitutive models are fitted through stress-strain curves obtained by experiments, the optimal constitutive is selected by comparing the experimental and simulation results of super-elastic micro-protrusion contact; the analytical solution of super-elastic micro-protrusion contact is fitted, and its applicability to different super-elastic micro-protrusion contact problems is verified; the structure forward design meeting the requirements of target sensitivity, pressure measurement range and linearity is realized; the sensitivity curve is obtained through the electrical contact experiment, and the feasibility of the design method is verified; based on the application scene and material performance, the upper limit of the sensitivity that can be achieved by the method is given. The method has important engineering application value in the field of flexible electronics, and its outstanding advantage lies in that the microstructure parameters can be directly calculated according to the target performance requirements of the pressure sensor, realizing the accurate mapping of "performance requirements-structure parameters".

The invention provides a low-speed flexible shaft-bearing system rotation error prediction method based on assembly deviation. The method comprises the following steps: firstly, acquiring initial poses of an inner ring and an outer ring under a global / local coordinate system; the pose, the geometric tolerance and the assembly deviation are mapped to a Hertz contact model, a bearing static contact mechanical model is established, and contact deformation and stress of a rolling body are calculated; shell flexible deformation caused by an axial load is introduced under a displacement pre-tightening working condition, a shafting mechanical equilibrium equation is constructed, and a system equilibrium attitude is obtained through nonlinear iteration solution; and calculating the variable rotating angle of the instantaneous rotating shaft relative to the ideal shaft determined by the center connecting line of the left and right inner rings under different rotating angles, and representing the rotating error by using the root mean square of the variable rotating angle. According to the method, the assembly deviation and the pre-tightening and structure flexible coupling effect are considered in a unified mode, and the rotation error of the low-speed flexible shaft system can be quantitatively predicted.

The invention discloses a method for calculating parameters of a slip clamp of road slope compensation tensioning equipment. A slip insert is equivalent to a contact body to act on a working anchorage device; enabling the contact between the slip insert and the working anchorage device to be equivalent to plane strain, and further constructing a slip insert-working anchorage device friction contact model; when the deformation of the metal material can reach the deformation energy required by the yield of the metal material, the metal material can yield or be subjected to brittle failure; constructing a slip insert-yield strength model according to the slip insert-yield strength model; and selecting the slips of which the parameters meet the stress requirements in combination with the engineering safety factor requirements. According to the method, the geotechnical engineering theory, the Hertz contact mechanics theory, the tribology and the elastic-plastic mechanics theory are combined, and the calculation method of the road slope engineering pre-stressed anchor cable compensation tensioning equipment clamp is provided for the first time; according to the method, anchor cable compensation tensioning equipment clamp materials are improved through calculation, the equipment range can be increased, the method is suitable for anchor cables with larger tonnage in original design, the fatigue life of a slip clamp is prolonged, and design parameters are optimized.

A shell-imitated rubber bushing design method based on a microcosmic contact mechanical model belongs to the technical field of rubber bushings, and comprises the following steps: designing a shell-imitated rubber knuckle bearing with a steel-rubber-steel interface synergistic structure; the method comprises the following steps: performing a uniaxial tensile test on a rubber bushing material to obtain stress-strain data, processing the test data by using a fitting tool, and selecting a rubber constitutive model according to a deviation value between a fitting curve and a test curve; performing contact stress analysis and static stiffness calculation on the bionic rubber bushing; the radial contact area of the rubber bushing is calculated, and the steel-rubber interface contact area is optimized by controlling the geometric angle and radius of a steel layer; and importing a single stress-strain result obtained by finite element analysis into fatigue analysis software, and predicting the fatigue life of the rubber bushing. The shell bionic structure is applied to the heavy-duty truck chassis rubber bushing, and the technical problems that an existing heavy-duty truck rubber bushing is insufficient in rigidity and prone to failure due to fatigue under high-strength dynamic loads are solved.

The application provides a floating wind power multi-field coupling calculation method based on SPH-DEM, and belongs to the field of ocean wind power engineering. The method simulates the hydrodynamics of seawater by SPH, analyzes the contact mechanics behavior of the floating body and the anchor chain by DEM, integrates the MoorDyn module to calculate the anchor chain tension, and constructs a fluid-structure-anchor chain coupling framework. The implementation includes: establishing the SPH and DEM models, setting the boundary and initial parameters; using GPU parallel technology to perform fluid, structure and anchor chain simulation; realizing multi-physical field coupling through data interaction, and dynamically adjusting the step length to ensure the stability of the calculation combined with the CFL criterion. Compared with the CFD and FEM methods, the method has both efficiency and accuracy, is suitable for response analysis and stability evaluation of floating wind power in extreme sea conditions, and the innovation lies in breaking through the multi-scale coupling calculation problem and realizing the collaborative calculation of the structure and the mooring system in a complex sea area.