A method and device for simulating flat tensile strength of a flat joint

Abstract

The application provides a flat tensile strength simulation analysis method and device of a flat joint, wherein the method comprises the following steps: intercepting part of the flat joint in a buckling state as an analysis model, and respectively modeling the inner tooth, outer tooth and base cloth of the analysis model; setting the contact parameters and material parameters of each part of the analysis model; setting the coordinate system of the analysis model; selecting the loading point and constraint point of the analysis model, adding corresponding constraints to the constraint point, and applying a flat tensile strength load to the loading point to perform simulation calculation; analyzing the simulation output result of the analysis model to determine the flat tensile strength load of the flat joint; measuring the inner tooth and outer tooth closest to the loading point or constraint point, intercepting a cross section at the middle position of the tooth width at the position, and taking the Z-direction distance value between the lowest point of the inner tooth root and the highest point of the outer tooth buckling area to determine whether the distance between the two is reduced from the initial value to 0; if so, the tensile constraint reaction force at this time is determined as the flat tensile strength load.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of flat joint, in particular to a flat joint flat tensile strength simulation analysis method and device. BACKGROUND

[0002] As a specially designed part, flat joint is mainly used to achieve gas sealing effect and is widely used in national defense and civil fields. Because it can effectively prevent gas penetration, it plays an indispensable role in occasions that require sealing protection. However, due to the relatively small market demand, this technical field has not received widespread research attention.

[0003] Although flat joint plays an irreplaceable role in a specific field, there are obvious defects in its design and testing process. At present, the design of flat joint mainly depends on the production and test of physical sample parts, and this method cannot evaluate and optimize the performance of flat joint at the early stage of design. In addition, due to the small size of flat joint structure, it is difficult to accurately measure the overall strength state (such as stress, strain, etc.) of flat joint in real time in actual test, which leads to low efficiency, long cycle and high cost in the design optimization process. SUMMARY

[0004] The present application provides a flat joint flat tensile strength simulation analysis method and device to solve the defects of low efficiency, long cycle and high cost in the design optimization process in the prior art.

[0005] The present application provides a flat joint flat tensile strength simulation analysis method, characterized in that the flat joint comprises inner teeth, outer teeth and base cloth, and the base cloth is located between the inner teeth and the outer teeth.

[0006] The method comprises:

[0007] Part of the flat joint in the buckling state is intercepted as an analysis model, and the inner teeth, outer teeth and base cloth of the analysis model are respectively modeled and processed;

[0008] The contact parameters and material parameters of each part of the analysis model are set;

[0009] The coordinate system of the analysis model is set; the length direction of the flat joint is the X direction of the analysis model, the direction of the applied flat tensile strength is the Y direction, and the direction perpendicular to the X direction and the Y direction is the Z direction;

[0010] The loading point and the constraint point of the analysis model are selected, the corresponding constraint is added to the constraint point, and the flat tensile strength load is applied to the loading point to perform simulation calculation;

[0011] The simulation output result of the analysis model is analyzed to determine the flat tensile strength load of the flat joint; wherein the inner tooth and the outer tooth closest to the loading point or the constraint point are measured, a section is cut in the middle position of the tooth width at the position, the Z direction distance value between the lowest point of the inner tooth root and the highest point of the outer tooth engagement area is taken to determine, if the distance between the two is reduced from the initial value to 0, the inner tooth is defined as out of engagement, and the tensile constraint reaction force of the analysis model at this time is determined as the flat tensile strength load.

[0012] According to the flat tensile strength simulation analysis method of the flat joint provided by the application, the inner tooth, the outer tooth and the base cloth of the analysis model are respectively modeled and processed, specifically including: the inner tooth of the analysis model is subjected to finite element mesh division to obtain the finite element model of the inner tooth; the outer tooth of the analysis model is subjected to finite element mesh division to obtain the finite element model of the outer tooth; the base cloth located on the base cloth sealing surface is subjected to mesh division in an interference state, and the base cloth at other positions is subjected to mesh division in an actual size state to obtain the finite element model of the base cloth, wherein the interference state is 5% to 30% of the average size of the mesh penetrating units of the base cloth sealing surface.

[0013] According to the flat tensile strength simulation analysis method of the flat joint provided by the application, the contact parameters of each part of the analysis model are set, specifically including:

[0014] The contact parameters between the inner tooth and the base cloth, the inner tooth and the inner tooth, and the base cloth sealing surface are set, wherein the normal contact between the inner tooth and the base cloth is set, the meshing area of the inner tooth and the inner tooth is set as normal contact, and the interference contact between the base cloth sealing surfaces is set; micro spring units are respectively arranged between the inner tooth and the base cloth, between the inner tooth and the inner tooth, and between the base cloth sealing surfaces, wherein the micro spring units are used to simulate the physical contact state change of the real contact area;

[0015] The material parameters of each part of the analysis model are set, specifically including: for the metal material corresponding to the inner tooth and the outer tooth, a nonlinear plastic material is created according to the test stress-strain curve; for the part of the base cloth located outside the outer tooth, a linear elastic material is set according to the base cloth elastic modulus parameter; for the base cloth located in the clamping range of the outer tooth, a nonlinear plastic material is set according to the material stress-strain curve.

[0016] According to the flat tensile strength simulation analysis method of the flat joint provided by the application, the loading point and the constraint point of the analysis model are selected, specifically including:

[0017] The intersection point of the cutting plane located in the middle position of the analysis model and the center line of the base cloth thickness is selected as the loading point and the constraint point; wherein the loading point is located in the Y positive direction, and the constraint point is located in the Y negative direction;

[0018] Taking the loading point as a main point, taking nodes within a set range from the loading point on two sides of the truncation plane as slave points, and establishing a rigid rod element of the base cloth on two sides of the loading point.

[0019] According to the plane joint provided by the application, the constraint point is added with corresponding constraints, and the loading point is applied with a plane tensile strength load, and the method specifically comprises the following steps:

[0020] The constraint point is added with translational freedom constraints in X, Y and Z directions and rotational freedom constraints around X, Y and Z axes.

[0021] The loading point is applied with a plane tensile strength load along the Y positive direction.

[0022] According to the plane joint provided by the application, before the simulation calculation is performed, the method further comprises the following steps:

[0023] A contact analysis control card is set, wherein the contact analysis comprises geometric large deformation nonlinear analysis and material nonlinear analysis, so as to ensure the accuracy of the simulation process;

[0024] A discontinuous calculation control card and a contact stability control card of each load step are set, so as to ensure the stability of the simulation process.

[0025] According to the plane joint provided by the application, the simulation output result of the analysis model is analyzed, and the method specifically comprises the following steps:

[0026] For each node in the analysis model, the node displacement, the constraint reaction force and the concentrated force are outputted;

[0027] For the rigid rod element, the stress distribution and the strain distribution are outputted;

[0028] For the contact pair, the contact stress and the contact displacement are outputted.

[0029] The application further provides a plane joint plane tensile strength simulation analysis device, and the plane joint comprises inner teeth, outer teeth and a base cloth, the base cloth is located between the inner teeth and the outer teeth, and the device comprises:

[0030] A modeling processing module is configured to intercept part of the plane joint in a buckling state as an analysis model, and model the inner teeth, the outer teeth and the base cloth of the analysis model respectively;

[0031] A parameter setting module is configured to set contact parameters and material parameters of each part of the analysis model;

[0032] The coordinate system setting module is used for setting a coordinate system of the analysis model; a length direction of the plane combination part is used as an X direction of the analysis model, a direction of applying the flat tensile strength is used as a Y direction, and a direction perpendicular to the X direction and the Y direction is used as a Z direction;

[0033] The constraint load setting module is used for selecting a loading point and a constraint point of the analysis model, adding corresponding constraints to the constraint point, and applying a flat tensile strength load to the loading point to perform simulation calculation.

[0034] The output result analysis module is used for analyzing simulation output results of the analysis model to determine the flat tensile strength load of the plane combination part; wherein the inner tooth and the outer tooth closest to the loading point or the constraint point are measured, a section is cut at a middle position of a tooth width of the position, a Z direction distance value between a lowest point of a tooth root of the inner tooth and a highest point of a meshing area of the outer tooth is taken to determine, and if the distance between the two points is reduced from an initial value to 0, the inner tooth is defined as being out of engagement, and the tensile constraint reaction force of the analysis model at this time is determined as the flat tensile strength load.

[0035] The application further provides an electronic device, including a memory, a processor, and a computer program stored in the memory and capable of running on the processor, and the processor implements the flat tensile strength simulation analysis method of the plane combination part according to any one of the above.

[0036] The application further provides a non-transitory computer readable storage medium, which stores a computer program, and the computer program is executed by a processor to implement the flat tensile strength simulation analysis method of the plane combination part according to any one of the above.

[0037] The application further provides a computer program product, which includes a computer program, and the computer program is executed by a processor to implement the flat tensile strength simulation analysis method of the plane combination part according to any one of the above.

[0038] The flat tensile strength simulation analysis method and device of the plane combination part provided by the application can evaluate and optimize the performance of the plane combination part at the initial design stage by establishing an analysis model of the plane combination part and simulating and analyzing the flat tensile strength of the plane combination part, and the efficiency of the traditional method which depends on the production and test of a physical sample is avoided; and the simulation analysis can comprehensively and real-timely measure the strength state of the plane combination part at a microscopic level, such as stress and strain, to provide more accurate data support for design optimization, and realize high efficiency, low cost, accurate performance prediction and optimization in the design process of the plane combination part. BRIEF DESCRIPTION OF DRAWINGS

[0039] In order to make the technical solutions in the present application or the prior art clearer, the accompanying drawings needed in the embodiments or the prior art description will be briefly introduced. Obviously, the accompanying drawings in the following description are only some embodiments of the present application, and other drawings can be obtained by those skilled in the art without any creative effort.

[0040] Figure 1 is a structural schematic diagram of the planar combination provided by the present application.

[0041] Figure 2 is a flat tensile strength test schematic diagram of the air-tight zipper provided by the present application.

[0042] Figure 3 is one of the flow schematic diagrams of the flat tensile strength simulation analysis method of the planar combination provided by the present application.

[0043] Figure 4 is the second flow schematic diagram of the flat tensile strength simulation analysis method of the planar combination provided by the present application.

[0044] Figure 5 is a non-structural round corner processing schematic diagram of the external tooth provided by the present application.

[0045] Figure 6a and Figure 6b is a finite element meshing schematic diagram of the external tooth and the internal tooth provided by the present application.

[0046] Figure 7 is a finite element meshing schematic diagram of the base cloth provided by the present application.

[0047] Figure 8 is a material property setting schematic diagram of each part of the air-tight zipper provided by the present application.

[0048] Figure 9 is a structural schematic diagram of the planar combination mesh model provided by the present application.

[0049] Figure 10 is a schematic diagram of the loading point and the constraint point position of the planar combination provided by the present application.

[0050] Figure 11 is a setting model constraint schematic diagram provided by the present application.

[0051] Figure 12 is a load loading schematic diagram of the model provided by the present application.

[0052] Figure 13a~Figure 1 3 c is a flat tensile strength load determination method schematic diagram provided by the present application.

[0053] Figure 14This is a schematic diagram of the Z-axis spacing and model constraint reaction force provided by the present invention.

[0054] Figure 15 This is a schematic diagram of the tensile strength simulation analysis device for planar joints provided by the present invention.

[0055] Figure 16 This is a schematic diagram of the structure of the electronic device provided by the present invention. Detailed Implementation

[0056] To make the objectives, technical solutions, and advantages of this invention clearer, the technical solutions of this invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of this invention. All other embodiments obtained by those skilled in the art based on the embodiments of this invention without creative effort are within the scope of protection of this invention.

[0057] First, the terminology used in the embodiments of this invention will be explained illustratively.

[0058] Airtight zippers: These are zippers with a special structural design that enables them to achieve a gas-tight seal. In this embodiment of the invention, the airtight zipper has an inner and outer tooth sealing structure. The inner teeth enable the zipper to engage, while the outer teeth compress and seal the base fabric joint surface.

[0059] Tensile strength refers to the ultimate load determined when a planar joint structure of a certain length fails, as required by the "QB / T2171 Zipper Standard" which involves a planar tensile test perpendicular to the length of the planar joint.

[0060] Base fabric: refers to the substrate fabric to which the planar connector is attached and connected. In this embodiment of the invention, to achieve a sealing effect, the base fabric is made of fiber cloth coated with TPU material. In the planar connector involved in this embodiment of the invention, the base fabric is sandwiched between the outer and inner teeth at the chain tooth position. The outer teeth apply pressure to the base fabric, causing the opposing base fabrics of the planar connector to be tightly pressed together, thereby achieving the function of sealing the mating surface of the planar connector.

[0061] Internal teeth: refers to the chain tooth structure used to realize the meshing of the planar joint in the planar joint. In the embodiments of the present invention, the internal teeth are roughly "I" shaped, wherein the root "I" part is wrapped by the base fabric and then wrapped and clamped by the outer teeth, and the tip "I" part is the part where the internal teeth mesh with each other.

[0062] Outer tooth: refers to the chain tooth structure in the plane joint for pressing the base cloth to realize the sealing effect. The shape of the outer tooth involved in the embodiment of the application is approximately "C" shape, the inner tooth root "I" shape is wrapped by the base cloth and embedded in the inner cavity of the outer tooth "C" shape, to realize the fixed connection of the inner tooth and the outer tooth. After the inner tooth is engaged, the outer tooth is pulled towards the opposite outer tooth. A pair of outer teeth form two opposite "C" shapes, the base cloth is clamped by the upper and lower lips of the opposite "C" shapes, to realize the sealing function of the joint surface of the plane joint.

[0063] Finite element method: the finite element method (FEM) is a mathematical method for solving engineering problems. The basic idea is to divide the calculation domain into a finite number of non-overlapping elements, select some appropriate nodes as interpolation points for solving functions in each element, and rewrite the variables in the differential equation into a linear expression composed of the node values of each variable or its derivative and the selected interpolation function. By means of variational principle or weighted residual method, the differential equation is discretely solved.

[0064] In the embodiment of the application, the structure of the plane joint is shown as Figure 1 In this embodiment, taking the airtight zipper as an example, the plane joint 10 includes an inner tooth 101, an outer tooth 102 and a base cloth 103, and the base cloth 103 is located between the inner tooth 101 and the outer tooth 102.

[0065] When designing the airtight zipper, it is necessary to meet certain flat pull strength bearing requirements. According to the "QB / T2171 Zipper Standard", the flat pull strength test is performed on a 75mm long zipper in a closed state, a 25mm wide clamp is used to clamp the base cloth on both sides, a tensile testing machine is used to stretch the base cloth on both sides, and the test is stopped when the teeth are pulled out or the base cloth is damaged. At this time, the tensile load is the flat pull strength value, and the test is shown as Figure 2 Therefore, it is necessary to propose an analysis method that can better simulate the flat pull strength test process for the plane joint. The flat pull strength performance of the plane joint can be calculated by numerical simulation in the early stage of the design of the plane joint, and whether the performance requirements are met can be evaluated.

[0066] To this end, the embodiment of the application proposes a flat pull strength simulation analysis method for a plane joint, which uses the finite element method to realize the flat pull strength simulation analysis and evaluation of the plane joint. As shown in Figure 3 The method comprises the following steps:

[0067] 301, a part of the plane joint in the closed state is intercepted as an analysis model, and the inner tooth, the outer tooth and the base cloth of the analysis model are respectively modeled and processed.

[0068] In this embodiment, according to the design data of the flat joint, the test condition requirements in the QB / T2171 flat joint standard are combined, and a 75mm long part of the flat joint in the fastening state of the finished product is intercepted as an analysis model.

[0069] A 75mm long part in the fastening state is intercepted from the finished flat joint to ensure that it contains complete internal teeth, external teeth, and base cloth structures. Detailed geometric data is obtained using high-precision scanning or measuring equipment to ensure the accuracy of the model. The intercepted part is digitally modeled to generate the corresponding model.

[0070] 302, set the contact parameters and material parameters of each part of the analysis model.

[0071] The internal teeth, external teeth, and base cloth are meshed with finite elements. For the internal teeth and external teeth of metal materials, a nonlinear plastic material model is set according to the stress-strain curve obtained by experiment. For the base cloth, a linear elastic material is set according to its elastic modulus; for the base cloth in the wrapping and clamping range of the external teeth, a nonlinear plastic material is set. When setting the contact parameters, the interactions between the internal teeth and the base cloth, the internal teeth and the internal teeth, and the sealing surface of the base cloth are considered, and normal contact and interference contact are set respectively, and appropriate friction coefficients and contact stiffnesses are set for these contact pairs.

[0072] 303, set the coordinate system of the analysis model; the length direction of the flat joint is the X direction of the analysis model, the direction of applying the flat tensile strength is the Y direction, and the direction perpendicular to the X direction and the Y direction is the Z direction.

[0073] At the middle position of the analysis model, the intersection point with the center line of the base cloth thickness is selected as the loading point and the constraint point. The loading point is located in the Y positive direction, and the constraint point is located in the Y negative direction. The rigid rod elements of the base cloth on both sides of the loading point are established to simulate the actual loading and constraint conditions. The constraint point is added with translational freedom constraints in X, Y, and Z directions and rotational freedom constraints around X, Y, and Z axes; the loading point is applied with a flat tensile strength load along the Y positive direction.

[0074] 304, select the loading point and the constraint point of the analysis model, and add corresponding constraints to the constraint point and apply a flat tensile strength load to the loading point for simulation calculation.

[0075] At the middle position of the analysis model, the intersection point with the center line of the base cloth thickness is selected as the loading point and the constraint point. The loading point is located in the Y positive direction, and the constraint point is located in the Y negative direction. The nodes within a set range from the loading point on both sides of the cutting plane are taken as slave points, and the rigid rod elements of the base cloth on both sides of the loading point are established to simulate the actual loading and constraint conditions.

[0076] Add translation freedom constraints of X, Y, Z directions and rotation freedom constraints around X, Y, Z axes to the constraint point; apply a flat tensile strength load along the positive Y direction to the loading point.

[0077] Before performing the simulation calculation, the method further comprises: setting a contact analysis control card, wherein the contact analysis comprises geometric large deformation nonlinear analysis and material nonlinear analysis to ensure the accuracy of the simulation process; setting a discontinuous calculation control card and a contact stability control card for each load step to ensure the stability of the simulation process.

[0078] Geometric large deformation nonlinearity: This refers to the deformation of the material or structure during loading, which may be so large that the effect of deformation on stress distribution cannot be ignored. In the flat tensile strength analysis of the flat coupling, the sprocket and the base cloth of the flat coupling may undergo significant deformation.

[0079] Material nonlinearity: The stress-strain relationship of the material is not linear and may exhibit elastic, plastic, creep, and other characteristics. In the analysis of the flat coupling, the materials of the sprocket and the base cloth may exhibit nonlinear stress-strain behavior.

[0080] In finite element analysis, a load step is a stage in the analysis process used to gradually apply loads and calculate structural responses. The concept of load step allows analysts to simulate the gradual increase of loads, which is very useful when simulating load conditions that change gradually in actual working conditions. Load steps are usually associated with time, and each load step can represent a specific time period during which the applied load is constant or changes according to a certain law.

[0081] In nonlinear analysis, such as geometric nonlinear or material nonlinear analysis, the load is not applied at once, but is gradually increased through multiple load steps, with each load step applying a portion of the load. This can avoid numerical problems caused by rapid changes in load.

[0082] Specifically, the discontinuous calculation control card is used to handle discontinuities that may occur in the model, such as contact separation or material yield. The contact stability control card is used to improve the stability of the contact algorithm, especially in cases where the contact area may change significantly.

[0083] 305、analyze the simulation output results of the analysis model to determine the flat tensile strength load of the flat coupling; wherein the inner and outer teeth closest to the loading point or the constraint point are measured, a cross section is taken at the middle of the tooth width at that position, and the Z-direction distance between the lowest point of the inner tooth root and the highest point of the outer tooth engagement area is taken as the judgment value. If the distance between the two is reduced from the initial value to 0, it is defined as the inner tooth coming out, and the tensile constraint reaction force of the analysis model at this time is determined as the flat tensile strength load.

[0084] The simulation output result of the analysis model is analyzed, specifically including: for each node in the analysis model, outputting node displacement, constraint reaction force and concentrated force; for the rigid rod element, outputting stress distribution and strain distribution; for the contact pair, outputting contact stress and contact displacement.

[0085] After the simulation calculation, the simulation output result is collected and analyzed. The output result includes the displacement of each node, the constraint reaction force and the concentrated force, the stress distribution and the strain distribution of the rigid rod element, and the contact stress and the contact displacement of the contact pair. Special attention is paid to the Z-direction distance value between the lowest point of the inner tooth root and the highest point of the outer tooth engagement area. When this distance is reduced from the initial value to 0, the tensile constraint reaction force at this time is recorded as the flat tensile strength load. In addition, a relationship curve between the Z-direction spacing and the model constraint reaction force is drawn to intuitively show the performance change of the flat joint during the force process.

[0086] The flat tensile strength simulation analysis method of the flat joint provided by the embodiment of the present application can evaluate and optimize the performance of the flat joint at the initial design stage by establishing an analysis model of the flat joint and simulating the flat tensile strength of the flat joint, thereby avoiding the low efficiency of the traditional method which relies on the production and test of physical samples. The simulation analysis can comprehensively and real-timely measure the strength state of the flat joint at the micro level, such as stress and strain, thereby providing more accurate data support for design optimization and realizing high efficiency, low cost, accurate performance prediction and optimization in the design process of the flat joint.

[0087] Further, referring to Figure 4 , the inner tooth, the outer tooth and the base cloth of the analysis model are respectively modeled and processed, specifically including:

[0088] 401. The inner tooth of the analysis model is subjected to finite element mesh division to obtain a finite element model of the inner tooth.

[0089] 402. The outer tooth of the analysis model is subjected to finite element mesh division to obtain a finite element model of the outer tooth.

[0090] The non-structural round corners at the section edges in the chain tooth structure which do not affect the stress are removed. In addition, all the round corner features of the outer profile of the tooth section are retained. The non-structural round corner processing schematic diagram of the outer tooth is shown in Figure 5 .

[0091] The analysis model after the adjustment processing is subjected to finite element mesh division. The analysis model adopts hexahedron and triangular prism solid elements for modeling. When the chain tooth is a symmetrical structure in the tooth width direction or the joint direction, the mesh division is performed in a symmetrical manner. When the chain tooth has two symmetrical axes, a 1 / 4 model is divided and symmetrical processing is performed. The finite element mesh division schematic diagrams of the outer tooth and the inner tooth are respectively shown in Figure 6aand Figure 6b As shown.

[0092] 403. Mesh the base fabric located on the sealing surface of the base fabric in an interference fit, and mesh the base fabric in other locations according to the actual size, to obtain the finite element model of the base fabric. The interference fit is 5% to 30% of the average size of the interpenetrating elements of the mesh on the sealing surface of the base fabric.

[0093] In this process, the base fabric between the inner and outer teeth is first wrapped around the inner teeth, and then squeezed and clamped by the partially closed inner cavity of the outer teeth, thus achieving the tight clamping and fixation of the inner and outer teeth on the base fabric. Therefore, in addition to uneven thickness, the base fabric is also subjected to strong compressive force from the outer teeth between the inner and outer teeth. Simulating the entire process would significantly increase the computational workload and reduce model stability and convergence. To simplify the model, this invention proposes a simplified modeling method that uses the gap between the inner and outer teeth in the finished planar joint state as the geometric boundary of the base fabric within this region. Simultaneously, in contact areas where the gap between the outer teeth and the base fabric is less than a certain value, a common-node method is used to connect the outer teeth and the base fabric. Except for the common-node areas, contact relationships are established between the outer teeth and the base fabric, and between the inner teeth and the base fabric, according to their actual states. For the base fabric between the sealing surfaces of the outer teeth, a certain interference contact is considered to simulate the sealing and clamping effect. When establishing the mesh, the base fabric sealing surface is established with an interference state (the sealing surface mesh penetrates each other by 5% to 30% of the average element size) at 5% to 30% of the average element size. The geometric features of the base fabric in other locations are modeled according to their actual dimensions. A schematic diagram of the finite element mesh generation for the base fabric is shown below. Figure 7 As shown.

[0094] Specifically, setting the contact parameters of each part of the analysis model in step 302 includes: setting the contact parameters between the inner teeth and the base fabric, between the inner teeth and the inner teeth, and between the base fabric sealing surfaces, wherein the contact between the inner teeth and the base fabric is set to normal contact, the meshing area between the inner teeth and the inner teeth is set to normal contact, and the contact between the base fabric sealing surfaces is set to interference contact; micro-spring units are respectively set between the inner teeth and the base fabric, between the inner teeth and the inner teeth, and between the base fabric sealing surfaces, wherein the micro-spring units are used to simulate the physical contact state changes of the actual contact areas.

[0095] Specifically, normal contact is established between the internal teeth and the base fabric, with a friction coefficient of 0.1~0.6; normal contact is established between the internal teeth in their meshing area, with a friction coefficient of 0.05~0.35. The base fabric sealing contact surface is provided with interference fit, the interference amount being 5%~30% of the average unit size, and the contact type being face-to-face small sliding contact, with a friction coefficient of 0.05~0.35. Except for the interference fit, all the above contacts require contact adjustment tolerances.

[0096] The micro spring unit is arranged to provide additional constraints to avoid local state mutation and calculation singularity of the model when the contact state changes, such as stress and deformation process, so as to improve the convergence of the analysis model. These micro spring units can significantly improve the stability and calculation efficiency of the model without affecting the calculation results. In actual simulation analysis, the setting of the micro spring unit needs to be determined according to the specific characteristics and simulation requirements between the contact pairs, so as to ensure the accuracy and reliability of the simulation analysis.

[0097] Specifically, the material parameters of each part of the analysis model set in step 302 specifically include: for the metal material corresponding to the inner tooth and the outer tooth, creating a nonlinear plastic material according to the test stress-strain curve; for the part of the base cloth outside the outer tooth, setting a linear elastic material according to the elastic modulus parameter of the base cloth; for the base cloth in the clamping range of the outer tooth, setting a nonlinear plastic material according to the material stress-strain curve.

[0098] For the sprocket metal material, a nonlinear plastic material is created according to the test stress-strain curve. For the base cloth material, the material setting needs to be performed in two parts. The base cloth material is generally orthotropic, which is simplified as isotropic material in the calculation model, and the material parameters are the elastic modulus and stress-strain curve of the base cloth in the flat tensile strength test direction. The part of the base cloth outside the outer tooth is mainly used for transmitting tensile load, which has no significant influence on the flat tensile strength calculation result. The base cloth material in the clamping range of the outer tooth is set as a nonlinear plastic material according to the material stress-strain curve, and the material attribute setting of each part is as shown in Figure 8 .

[0099] Specifically, in order to understand the technical solutions of the embodiments of the present application, steps 1-14 are described below.

[0100] Step 1: intercept the detailed analysis model of the flat joint in the buckling state with a length of 75 mm. Remove the non-structural round corners in the sprocket structure that do not affect the stress. In addition, all the round corner features of the tooth-shaped cross section are retained, as shown in Figure 5 .

[0101] Step 2: model the inner tooth and the outer tooth of the analysis model respectively, as shown in FIG. 6.

[0102] Step 3: process the base cloth model. The base cloth on the base cloth sealing surface is modeled in an interference state with an average element size of 5%-30%, and the base cloth at other positions is modeled in an actual size state, as shown in Figure 7 .

[0103] Step 4: set the contact parameters of the inner tooth and the base cloth, the inner tooth and the inner tooth, and the base cloth sealing surface.

[0104] The normal contact is arranged between the inner teeth and the base cloth, the friction coefficient of the contact surface is 0.1-0.6, the normal contact is arranged in the meshing area of the inner teeth, and the friction coefficient of the contact surface is 0.05-0.35. The interference contact is arranged on the base cloth sealing contact surface, the interference amount is 5%-30% of the average size of the unit, the contact type is face-to-face small sliding contact, and the friction coefficient of the contact surface is 0.05-0.35. In addition to the interference contact, the above-mentioned contact needs to be provided with a contact adjustment tolerance.

[0105] Step 5: A micro-spring unit is arranged between the contacts, which is used to simulate the physical contact state change of the real contact area.

[0106] Specifically, the flat joint piece flat tensile strength analysis involves a large number of nonlinear calculations such as geometry, contact and material nonlinearity, and the contact nonlinearity is a common and frequent factor leading to model divergence. This is mainly because the model connected by pure contact changes the contact state during stress and deformation, and the local state may suddenly change and the calculation may be singular due to the lack of more constraints, thereby causing divergence. To solve this problem, the present application proposes to establish a micro-spring unit between all contact connectors that can constrain the relative rigid body motion of the two pieces, and by setting appropriate spring unit stiffness, the model convergence can be significantly improved without affecting the calculation results. The established flat joint piece grid model is as shown in Figure 9 .

[0107] Step 6: Set the material parameters of each part of the model; for the chain tooth metal material, create a nonlinear plastic material according to the test stress-strain curve; for the base cloth material, the material setting needs to be divided into two parts: for the part of the base cloth material located outside the outer teeth, set the linear elastic material according to the base cloth elastic modulus parameter; for the base cloth material in the clamping range of the outer teeth, set the nonlinear plastic material according to the material stress-strain curve, as shown in Figure 8 .

[0108] Step 7: Establish the constraint and loading unit, the loading point and the constraint point of the flat tensile strength analysis model are located on the truncated plane of half the length of the flat joint piece, and the intersection point of the plane and the center line of the base cloth thickness is taken as the loading point or the constraint point. Take this point as the main point, and the nodes within the range of 12.5mm on both sides of the base cloth cross section from the point as the from points, and establish the rigid rod units of the base cloth on both sides, and the loading point and the constraint point are as shown in Figure 10 . The constraint point is located on the other side of the flat joint piece, opposite to the loading point.

[0109] Step 8: Set the analysis coordinate system of the model. The length direction of the flat joint piece is taken as the X direction of the analysis model, the direction of the applied flat tensile strength is taken as the Y direction, and the direction perpendicular to the X direction and the Y direction is taken as the Z direction, as shown in Figure 7 .

[0110] Step 9: Set model constraints.

[0111] Add translation freedom constraints in X, Y, Z directions and rotation freedom constraints around X, Y, Z axes for the constraint point; apply a positive Y-directional tensile force load to the loading point, as shown in Figure 11 .

[0112] In finite element analysis, dof (degrees of freedom) is the freedom, and each freedom represents the movement or rotation ability in one direction. In three-dimensional space, a point has 6 degrees of freedom, corresponding to three translation directions (X, Y, Z) and three rotation directions (rotation around X axis, rotation around Y axis, rotation around Z axis). These freedoms are usually represented by numbers 1 to 6, where: dof1: X-direction translation; dof2: Y-direction translation; dof3: Z-direction translation; dof4: rotation around X axis; dof5: rotation around Y axis; dof6: rotation around Z axis.

[0113] For the constraint point, the freedom is dof123456; for the loading point, the freedom is dof1356.

[0114] Step 10: Set the contact analysis control card, which includes geometric large deformation nonlinear analysis and material nonlinear analysis to ensure the accuracy of the simulation process.

[0115] Set the discontinuous calculation control card and contact stability control card for each load step to ensure the stability of the simulation process.

[0116] Step 11: Set the calculation output. For nodes, set the output node displacement, constraint reaction force, and concentrated force; for elements, set the output stress and strain; for contact pairs, set the output contact stress and contact displacement.

[0117] Step 12: Set the load, and use 8mm forced displacement for the tensile strength analysis. Apply a Y-direction 8mm forced displacement load to the loading point and establish the corresponding solution load step. The model load loading schematic is shown in Figure 12 .

[0118] Step 13: Solve the analysis and get the output results of each concerned data.

[0119] In the plane joint tensile strength simulation analysis, the simulation output results usually include the following aspects:

[0120] Node displacement: the displacement of each node in the model after being stressed, including displacement in X, Y, Z directions.

[0121] Stress distribution: the stress state of each element in the model, including normal stress (tensile and compressive stress) and shear stress.

[0122] Strain distribution: the strain state of each element in the model, including normal strain and shear strain.

[0123] Contact stress: the stress distribution on the contact surface, especially the stress state in the contact area between the chain tooth and the base cloth.

[0124] Contact displacement: the displacement of the contact surface, including separation and slip of the contact surface.

[0125] Constraint reaction force: the reaction force generated at the constraint point due to the applied load.

[0126] Concentrated force: the size and direction of the force applied at the loading point.

[0127] Plastic strain: if the material model includes plasticity, the distribution of plastic strain is also part of the simulation output.

[0128] Energy absorption: the energy absorbed by the model during the stretching process, including elastic energy and plastic energy.

[0129] Failure mode: the failure mode that may occur in the model during the force process, such as chain tooth disengagement, base cloth tearing, etc.

[0130] Tensile strength load: determine the tensile strength load of the plane joint by analyzing the disengagement of the inner and outer teeth.

[0131] Load-displacement curve: the relationship curve between the displacement of the loading point and the constraint reaction force, used to evaluate the load-carrying capacity of the plane joint.

[0132] Contact state change: the contact state between contact pairs, such as contact area, contact pressure, etc. change over time or load.

[0133] Step 14: Tensile strength load determination method: measure the inner and outer teeth closest to the loading point or constraint point. Take a cross section at the middle of the tooth width at this position, and take the Z-direction distance between the lowest point of the inner tooth root and the highest point of the outer tooth engagement area to determine, that is, when the distance between the two is reduced from the initial value to 0, it is defined as the disengagement of the inner tooth, at this time the tensile constraint reaction force of the model is determined as the tensile strength load.

[0134] The tensile strength load determination method is shown in Figure 13a~Figure 13c , where the initial z-direction distance is shown in Figure 13b , and the disengagement z-direction distance is shown in Figure 13c .

[0135] Measure the Z-direction distance of the above measurement points and the model constraint reaction force, and output the relationship curve of the two.Figure 14 As shown in the figure, the inner tooth is out of engagement under the condition of 600N flat tensile strength load.

[0136] The flat tensile strength simulation analysis device of the plane joint provided by the embodiment of the present application is described below, and the flat tensile strength simulation analysis device of the plane joint described below can be correspondingly referred to the flat tensile strength simulation analysis method of the plane joint described above.

[0137] The embodiment of the present application provides a flat tensile strength simulation analysis device of a plane joint, referring to Figure 15 , comprising:

[0138] The modeling processing module 1501 is configured to intercept part of the plane joint in the buckling state as an analysis model, and model the inner tooth, the outer tooth and the base cloth of the analysis model respectively;

[0139] The parameter setting module 1502 is configured to set the contact parameters and material parameters of each part of the analysis model;

[0140] The coordinate system setting module 1503 is configured to set the coordinate system of the analysis model; the length direction of the plane joint is the X direction of the analysis model, the direction of the applied flat tensile strength is the Y direction, and the direction perpendicular to the X direction and the Y direction is the Z direction;

[0141] The constraint load setting module 1504 is configured to select the loading point and the constraint point of the analysis model, add corresponding constraints to the constraint point, and apply a flat tensile strength load to the loading point for simulation calculation;

[0142] The output result analysis module 1505 is configured to analyze the simulation output result of the analysis model to determine the flat tensile strength load of the plane joint; wherein the inner tooth and the outer tooth closest to the loading point or the constraint point are measured, the section is intercepted at the middle position of the tooth width at this position, and the Z direction distance value between the lowest point of the inner tooth root and the highest point of the outer tooth buckling area is taken to determine whether the inner tooth is out of engagement, if the distance between the two is reduced from the initial value to 0, the inner tooth is defined as out of engagement, and the tensile constraint reaction force of the analysis model at this time is determined as the flat tensile strength load.

[0143] Figure 16 An example of a schematic diagram of the physical structure of an electronic device is shown in FIG. Figure 16As shown, the electronic device can include a processor 1610, a communications interface 1620, a memory 1630, and a communications bus 1640, wherein the processor 1610, the communications interface 1620, and the memory 1630 complete mutual communication through the communications bus 1640. The processor 1610 can invoke a logical instruction in the memory 1630 to perform a flat coupling piece flat tensile strength simulation analysis method, which includes: intercepting part of the flat coupling piece in the buckling state as an analysis model, respectively modeling the inner teeth, outer teeth and base cloth of the analysis model; setting the contact parameters and material parameters of each part of the analysis model; setting the coordinate system of the analysis model; taking the length direction of the flat coupling piece as the X direction of the analysis model, taking the direction of applying the flat tensile strength as the Y direction, and taking the direction perpendicular to the X direction and the Y direction as the Z direction; selecting the loading point and the constraint point of the analysis model, and adding corresponding constraints to the constraint point, and applying a flat tensile strength load to the loading point to perform simulation calculation; analyzing the simulation output result of the analysis model to determine the flat tensile strength load of the flat coupling piece; wherein the inner teeth and the outer teeth closest to the loading point or the constraint point are measured, a cross section is intercepted at the middle position of the tooth width at this position, and the Z direction distance value between the inner tooth root lowest point and the outer tooth buckling area highest point is taken to judge, if the distance between the two is reduced from the initial value to 0, it is defined as the inner tooth out of the way, and the tensile constraint reaction force of the analysis model at this time is determined as the flat tensile strength load.

[0144] In addition, the logical instruction in the memory 1630 described above can be realized in the form of a software function unit and sold or used as an independent product, which can be stored in a computer readable storage medium. Based on such understanding, the technical solutions of the present application essentially or the part that contributes to the prior art or part of the technical solutions can be embodied in the form of a software product, and the computer software product stored in a storage medium includes a plurality of instructions for making a computer device (which can be a personal computer, a server, or a network device, etc.) execute all or part of the steps of the method described in various embodiments of the present application. The foregoing storage medium includes: a U disk, a mobile hard disk, a read-only memory (ROM, Read-Only Memory), a random access memory (RAM, Random Access Memory), a magnetic disk or an optical disk, and various program code storage media.

[0145] On the other hand, the present application also provides a computer program product, which includes a computer program, the computer program can be stored on a non-transitory computer readable storage medium, and the computer program can be executed by a processor to enable a computer to perform the flat tensile strength simulation analysis method of the flat coupling piece provided by the above-mentioned method.

[0146] In yet another aspect, the present application also provides a non-transitory computer readable storage medium having stored thereon a computer program, which, when executed by a processor, implements the flat tensile strength simulation analysis method of the flat joint provided by each of the above methods.

[0147] The device embodiments described above are merely illustrative, wherein the units described as separate components can or can not be physically separate, and the components displayed as units can or can not be physical units, i.e., can be located in one place, or can be distributed to multiple network units. Part or all of the modules can be selected to achieve the purpose of the embodiment scheme according to actual needs. Those skilled in the art can understand and implement it without creative labor.

[0148] From the above description of the embodiments, those skilled in the art can clearly understand that each embodiment can be realized by means of software plus the necessary general hardware platform, and of course can also be realized by hardware. Based on such understanding, the above technical solutions, essentially or in other words, the part that contributes to the prior art, can be embodied in the form of a software product, which can be stored in a computer readable storage medium, such as a ROM / RAM, a magnetic disk, an optical disk, etc., and includes a number of instructions to make a computer device (which can be a personal computer, a server, or a network device, etc.) execute the methods described in each embodiment or some parts of the embodiments.

[0149] Finally, it should be noted that: the above embodiments are only used to illustrate the technical solutions of the present application, and not to limit them; although the present application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that: it can still modify the technical solutions recorded in the foregoing embodiments, or make equivalent replacement to some technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present application.

Claims

1. A method for simulating flat tensile strength of a flat joint, characterized by, The flat coupling comprises inner teeth, outer teeth and a base cloth, and the base cloth is located between the inner teeth and the outer teeth; The method comprises: A part of the flat coupling in the buckling state is intercepted as an analysis model, and the inner teeth, the outer teeth and the base cloth of the analysis model are respectively modeled and processed; Contact parameters and material parameters of each part of the analysis model are set; A coordinate system of the analysis model is set; a length direction of the flat coupling is an X direction of the analysis model, a direction in which a flat tensile strength is applied is a Y direction, and a direction perpendicular to the X direction and the Y direction is a Z direction; Loading points and constraint points of the analysis model are selected, and corresponding constraints are added to the constraint points, and a flat tensile strength load is applied to the loading points, so as to perform simulation calculation; The simulation output result of the analysis model is analyzed, and the flat tensile strength load of the flat coupling is determined; wherein, the inner teeth and the outer teeth closest to the loading points or the constraint points are measured, a cross section is intercepted at a middle position of a tooth width of the inner teeth and the outer teeth closest to the loading points or the constraint points, a Z direction distance value between a lowest point of a tooth root of the inner teeth and a highest point of a buckling area of the outer teeth is taken for judgment, and if the distance between the two is reduced from an initial value to 0, the inner teeth are defined as being out of engagement, and a tensile constraint reaction force of the analysis model at this time is determined as the flat tensile strength load.

2. The method of claim 1, wherein, The inner teeth, the outer teeth and the base cloth of the analysis model are respectively modeled and processed, and the modeling and processing specifically comprises: The inner teeth of the analysis model are subjected to finite element mesh division, so as to obtain a finite element model of the inner teeth; The outer teeth of the analysis model are subjected to finite element mesh division, so as to obtain a finite element model of the outer teeth; The base cloth located on the base cloth sealing surface is subjected to mesh division in an interference state, and the base cloth at other positions is subjected to mesh division according to an actual size state, so as to obtain a finite element model of the base cloth, wherein, the interference state is 5% to 30% of an average size of the mesh penetrating units of the base cloth sealing surface.

3. The method of claim 1, wherein, The contact parameters of each part of the analysis model are set, and the setting specifically comprises: The contact parameters between the inner teeth and the base cloth, the inner teeth and the inner teeth, and the base cloth sealing surface are set, wherein, the inner teeth and the base cloth are set as normal contact, the meshing area of the inner teeth and the inner teeth is set as normal contact, and the base cloth sealing surfaces are set as interference contact; Micro spring units are respectively arranged between the inner teeth and the base cloth, between the inner teeth and the inner teeth, and between the base cloth sealing surfaces, wherein, the micro spring units are used for simulating the physical contact state change of the actual contact area; The material parameters of each part of the analysis model are set, and the setting specifically comprises: For the metal materials corresponding to the inner teeth and the outer teeth, nonlinear plastic materials are created according to test stress-strain curves; For the part of the base cloth outside the outer teeth, linear elastic materials are set according to the elastic modulus parameters of the base cloth, and for the base cloth located in the clamping range of the outer teeth, nonlinear plastic materials are set according to the stress-strain curves of the materials.

4. The method of claim 1, wherein, The loading points and the constraint points of the analysis model are selected, and the selection specifically comprises: An intersection point of a cutting plane located at a middle position of the analysis model and a center line of the base cloth thickness is selected as the loading point and the constraint point; wherein, the loading point is located at a Y positive direction, and the constraint point is located at a Y negative direction. The rigid rod element of the base cloth on both sides of the loading point is established by taking the loading point as a main point and taking the nodes within a set range from the loading point on both sides of the truncation plane as slave points.

5. The method of claim 1, wherein, The constraint point is added with corresponding constraints, and the loading point is applied with a flat tensile strength load, specifically including: The constraint point is added with X, Y and Z direction translation freedom constraints and rotation freedom constraints around X, Y and Z axes. The loading point is applied with a flat tensile strength load along the Y positive direction.

6. The method of flatwise tensile strength simulation analysis of plane joints according to claim 1 or 5, characterized in that, Before the simulation calculation, the method further includes: The contact analysis control card is set, wherein the contact analysis includes geometric large deformation nonlinear analysis and material nonlinear analysis, so as to ensure the accuracy of the simulation process; The discontinuous calculation control card and the contact stability control card of each load step are set, so as to ensure the stability of the simulation process.

7. The method of claim 4, wherein, The simulation output result of the analysis model is analyzed, specifically including: For each node in the analysis model, the node displacement, constraint reaction force and concentrated force are outputted; For the rigid rod element, the stress distribution and strain distribution are outputted; For the contact pair, the contact stress and contact displacement are outputted.

8. A simulation analysis device for the tensile strength of a planar joint, characterized in that, The flat joint includes inner teeth, outer teeth and a base cloth, and the base cloth is located between the inner teeth and the outer teeth. The device includes: The modeling processing module is configured to intercept part of the flat joint in the buckling state as an analysis model, and model the inner teeth, the outer teeth and the base cloth of the analysis model respectively; The parameter setting module is configured to set the contact parameters and the material parameters of each part of the analysis model; The coordinate system setting module is configured to set the coordinate system of the analysis model, wherein the length direction of the flat joint is the X direction of the analysis model, the direction in which the flat tensile strength is applied is the Y direction, and the direction perpendicular to the X direction and the Y direction is the Z direction; The constraint load setting module is configured to select the loading point and the constraint point of the analysis model, add corresponding constraints to the constraint point, and apply a flat tensile strength load to the loading point, so as to perform simulation calculation; The output result analysis module is configured to analyze the simulation output result of the analysis model, and determine the flat tensile strength load of the flat joint; wherein the inner teeth and the outer teeth closest to the loading point or the constraint point are measured, a cross section is intercepted at the middle position of the tooth width of the inner teeth and the outer teeth closest to the loading point or the constraint point, the Z direction distance value between the lowest point of the inner teeth tooth root and the highest point of the outer teeth buckling area is taken for judgment, and if the distance between the two is reduced from the initial value to 0, the inner teeth are defined as out of engagement, and the tensile constraint reaction force of the analysis model at this time is determined as the flat tensile strength load.

9. An electronic device comprising a memory, a processor, and a computer program stored on the memory and executable on the processor, characterized in that, The processor executes the program to implement the flat tensile strength simulation analysis method of the flat joint according to any one of claims 1 to 7.

10. A non-transitory computer-readable storage medium having stored thereon a computer program, characterized in that, The computer program is executed by the processor to implement the flat tensile strength simulation analysis method of the flat joint according to any one of claims 1 to 7.

Images