Clutch pressure plate thermal deformation simulation method, system, equipment and medium

Abstract

The invention provides a clutch pressure plate thermal deformation simulation method, system and device and a medium, and belongs to the technical field of automobile clutches. A three-dimensional model of a dry diaphragm spring clutch is obtained, and a clutch heat engine coupling deformation finite element model is established; setting a constraint set point at a preset position; calculating the density of heat flow applied to the friction surface of the pressure plate; respectively calculating a pressure plate temperature field simulation result and a pressure plate thermal mechanical coupling deformation simulation result; outputting a calculation result as a simulation result file; and configuring the thermomechanical coupling deformation simulation result of the pressure plate to the temperature distribution cloud chart of the pressure plate, respectively extracting and analyzing the axial displacement of the inner side and the outer side of the friction surface of the pressure plate, and calculating to obtain the thermomechanical coupling deformation of the pressure plate. According to the method, multiple aspects such as heat flow density application, heat conduction, mechanical load application and heat engine coupling are comprehensively considered, the actual working condition of the clutch can be reflected, and the design and optimization requirements of the clutch are met.

Description

Technical Field

[0001] The present invention belongs to the technical field of automotive clutches, and particularly relates to a method, system, device and medium for simulating the thermal deformation of a clutch pressure plate. Background Art

[0002] During the engagement process of the clutch, the diaphragm spring applies a pressing force to the pressure plate, and the power is transmitted to the gearbox through the sliding friction of the pressure plate, flywheel and friction plate. However, a large amount of heat is generated during the sliding friction process, causing the temperature of the pressure plate to rise sharply, resulting in thermal deformation of the pressure plate in the form of inward convexity. The thermal deformation of the pressure plate will cause uneven contact during the sliding friction of the friction pair, generating local high-pressure areas, resulting in local high temperatures, and ultimately leading to thermal ablation of the clutch. Therefore, the thermal deformation amount of the clutch needs to be controlled within a reasonable range.

[0003] In the related art, when analyzing the thermal deformation amount of the clutch, the thermal analysis and the mechanical deformation analysis are separated, ignoring the interaction between the temperature field and the mechanical load, such as the change in contact pressure caused by thermal expansion, which in turn affects frictional heat generation. This leads to distortion of the physical field simulation results. For example, using steady-state thermal analysis cannot accurately simulate the transient change of the heat flux density during the clutch engagement-separation process. As a result, the simulation structure of the thermal deformation of the clutch pressure plate cannot meet the requirements. Summary of the Invention

[0004] The present invention provides a method for simulating the thermal deformation of a clutch pressure plate. By simulating the thermal deformation of the clutch pressure plate, problems existing in the pressure plate design can be discovered in time, avoiding failures such as thermal ablation during actual use, thereby improving the design reliability of the clutch pressure plate.

[0005] The method includes: obtaining three-dimensional models of the pressure plate, driven plate assembly, and flywheel of a dry diaphragm spring clutch, and establishing a finite element model of the pressure plate temperature field; Based on the obtained three-dimensional models of the pressure plate, driven plate assembly, and flywheel of the dry diaphragm spring clutch, establishing a finite element model of the thermo-mechanical coupling deformation of the clutch, and setting constraint set points at preset positions; Based on the operating conditions of the dry diaphragm spring clutch, determining the contact pressure p, rotational speed n, engagement time t1, and friction coefficient μ of the friction surface of the clutch pressure plate, and calculating the heat flux density ψ applied to the friction surface of the pressure plate; Based on the heat flux density and the finite element model of the pressure plate temperature field, calculating the simulation results of the thermo-mechanical coupling deformation of the pressure plate under different analysis step temperature fields; Based on the finite element model of the thermo-mechanical coupling deformation of the clutch, calculating the thermal deformation amount of the pressure plate at different analysis steps, and outputting the calculation results as a simulation result file; Configure the simulation results of the thermo-mechanical coupling deformation of the pressure plate into the temperature distribution contour map of the pressure plate, display the maximum and minimum values of the axial displacement in the temperature distribution contour map, extract the axial displacement amounts on the inner and outer sides of the friction surface of the pressure plate in the analysis step respectively, and calculate the thermo-mechanical coupling deformation amount of the pressure plate.

[0006] It should be further noted that the calculation formula for the heat flux density ψ is: ψ = p × n × t1 × μ.

[0007] It should be further noted that the methods for calculating the simulation results of the thermo-mechanical coupling deformation of the pressure plate under the temperature fields of different analysis steps include: Step S201: Apply the calculated heat flux density to the friction surface of the pressure plate within the engagement time t1. Step S202: Do not apply the heat flux density within the heat transfer time t2, and only conduct heat transfer inside the pressure plate. Step S203: Repeat the calculation steps S201 and S202 until the temperature of the pressure plate rises from the initial temperature to the preset temperature, and obtain the simulation results of the temperature field distribution of the pressure plate under different analysis steps.

[0008] It should be further noted that the steps for calculating the thermal deformation amount of the pressure plate in different analysis steps based on the finite element model of the clutch thermo-mechanical coupling deformation and outputting the calculation results as simulation result files further include: Step S204: Apply a specified pre-compression force in the axial direction at the axial direction of the pressure plate pressing force constraint set point P5 to establish pre-contact between the pressure plate and the friction plate and between the friction plate and the flywheel. Step S205: Apply a specified diaphragm spring pressing force in the axial direction at the axial direction of the pressure plate pressing force constraint set point P5. Step S206: Apply a preset engine torque in the rotational direction around the axis at the flywheel inner side constraint set point P2 and the pressure plate constraint set point P4 respectively. Step S207: Read the temperature fields of the pressure plate generated in steps S201 to S203 in all or some of the analysis steps, and input them one by one into step S206 after loading the mechanical load in the finite element model of the clutch thermo-mechanical coupling deformation to obtain the simulation results of the thermo-mechanical coupling deformation of the pressure plate under the temperature fields of different analysis steps.

[0009] It should be further noted that in the method, the flywheel outer side constraint set point P1, the flywheel inner side constraint set point P2, the large steel sheet constraint set point P3, the pressure plate constraint set point P4, and the pressure plate pressing force constraint set point P5 are defined respectively. Set the outer flywheel constraint set point P1 and the inner flywheel constraint set point P2 as fully free constraints, and set the large steel sheet constraint set point P3 as the other five degrees of freedom constraints except axial translation; set the pressure plate constraint set point P4 as the other four degrees of freedom constraints except axial translation and rotation about the axis; Establish contact constraints between the pressure plate and the friction plate, and between the flywheel and the friction plate, and establish binding constraints between the friction plate, the wave washer, and the large steel sheet; Configure the material property parameters, set the constraints and loads, and calculate the finite element model of the pressure plate temperature field according to steps S201 to S203 to obtain the calculation results of the pressure plate temperature field; Calculate the finite element model of the clutch thermal-mechanical coupling deformation according to steps S204 to S207 to obtain the calculation results of the pressure plate thermal deformation; Configure the calculation results of the pressure plate temperature field and the pressure plate thermal deformation as the simulation result file; Retrieve the displacement distribution nephogram in the axial direction of the pressure plate friction surface, display the maximum and minimum values of the axial displacement in the figure, and extract the axial displacement amounts on the inner and outer sides of the pressure plate friction surface respectively; Subtract the axial displacement amount on the outer side of the pressure plate friction surface from the axial displacement amount on the inner side of the pressure plate friction surface to obtain the thermal-mechanical coupling deformation amount of the pressure plate.

[0010] Furthermore, it should be noted that the steps of configuring the material property parameters, setting the constraints and loads also include: Define the contact constraints between the pressure plate and the friction plate, and between the flywheel and the friction plate, and establish binding constraints between the contact surfaces of the friction plate, the wave washer, and the large steel sheet; Define the bolts as the constrained fixed components; Set the material properties based on the elastic modulus, Poisson's ratio, density, coefficient of thermal expansion, and thermal conductivity; Set the optional time increment of the analysis step to 10s, or 20s, or 50s; Define the loading methods of the analysis step to include: pre-tightening force, torque, and temperature field.

[0011] Furthermore, it should be noted that the method also includes: applying a heat flux density that varies linearly with time on the pressure plate friction surface ; , where, t ≤ t P ; t is used to describe the time during the entire heat conduction process; Based on the process of heat diffusing from the high-temperature region to the low-temperature region inside the pressure plate material, etc., obtain the change of the temperature inside the pressure plate with time and space within a preset time period through the following transient heat conduction calculation formula; The transient heat conduction calculation formula is: ; is the density, is the specific heat capacity, and T represents the temperature, indicating the temperature value at a certain point in three-dimensional space at a certain moment; Repeat the above process until the temperature of the pressure plate reaches the preset target value; In the method, a pre-contact axial force of 100 N is applied at the pressure plate clamping force constraint set point P5; the dynamic diaphragm spring clamping force is input according to the clutch model; Torques NB = F·r around the axial direction are applied at the flywheel inner side constraint set point P2 and the pressure plate constraint set point P4; Map the temperature field results to the mechanical model, and calculate the stress of the thermoelastic material under force and temperature changes through the following formula to obtain the coupling effect of thermal expansion and mechanical stress; ; where C is the elastic stiffness matrix, is the strain, is the coefficient of thermal expansion, and I is the unit tensor; Based on the output pressure plate axial displacement nephogram, calculate the thermal deformation amount Bq as: Bq = B1 + B2; B1 is the deformation amount generated under mechanical stresses such as the diaphragm spring clamping force and engine torque; B2 is the deformation amount generated by thermal expansion.

[0012] This application also provides a clutch pressure plate thermal deformation simulation system, which includes: A pressure plate temperature field model establishment module, which is used to obtain the three-dimensional models of the pressure plate, driven plate assembly, and flywheel of the dry diaphragm spring clutch, and establish a finite element model of the pressure plate temperature field; A constraint set point configuration module, which is used to obtain the three-dimensional models of the pressure plate, driven plate assembly, and flywheel of the dry diaphragm spring clutch to establish a finite element model of the clutch thermo-mechanical coupling deformation, and set constraint set points at preset positions; A parameter calculation module, which is used to determine the contact pressure p, rotational speed n, engagement time t1, and friction coefficient μ of the clutch pressure plate friction surface in combination with the operating conditions of the dry diaphragm spring clutch, and calculate the heat flux density ψ applied to the pressure plate friction surface; A simulation parameter calculation module, which is used to calculate the simulation results of the pressure plate thermo-mechanical coupling deformation under different analysis step temperature fields in combination with the heat flux density and the finite element model of the pressure plate temperature field; A simulation processing module, which is used to calculate the thermal deformation amount of the pressure plate at different analysis steps in combination with the finite element model of the clutch thermo-mechanical coupling deformation, and output the calculation results as a simulation result file; The deformation amount calculation module is used to configure the thermo-mechanical coupling deformation simulation result of the pressure plate into the temperature distribution nephogram of the pressure plate, display the maximum and minimum values of the axial displacement in the temperature distribution nephogram, respectively extract the axial displacement amounts on the inner and outer sides of the friction surface of the pressure plate in the analysis step, and calculate the thermo-mechanical coupling deformation amount of the pressure plate.

[0013] According to another embodiment of the present application, an electronic device is provided, including a memory, a processor, and a computer program stored on the memory and executable on the processor. When the processor executes the program, the steps of the clutch pressure plate thermal deformation simulation method are implemented.

[0014] According to still another embodiment of the present application, a storage medium is further provided, on which a computer program is stored. When the computer program is executed by a processor, the steps of the clutch pressure plate thermal deformation simulation method are implemented.

[0015] As can be seen from the above technical solutions, the present invention has the following advantages: The present application provides a method for dynamically associating a temperature field with mechanical deformation by establishing a thermo-mechanical coupling deformation finite element model, solving the problem of distorted physical field simulation results. By means of step-by-step cyclic loading of heat flow and heat transfer, the dynamic evolution process of the temperature field of the pressure plate can be captured. By configuring the extreme values of axial displacement through the temperature distribution nephogram and extracting the displacement amounts on the inner and outer sides of the friction surface, the structural information of the pressure plate is analyzed.

[0016] The present application also dynamically couples the transient temperature field, that is, linear heat flow loading and intermittent heat transfer, with preloading force, spring force, and torque, truly reflecting the mutual feedback of heat and force in the clutch engagement-separation cycle. By adjusting parameters such as the friction coefficient, contact pressure, and engine torque, different models of clutches can be adapted. And by extracting the axial displacement amounts on the inner and outer sides of the friction surface, the warping mode of the pressure plate is clarified, providing direct data support for optimizing the thickness distribution and heat dissipation structure of the pressure plate.

[0017] The present application establishes the outer flywheel constraint set point P1, the inner flywheel constraint set point P2, the large steel sheet constraint set point P3, the pressure plate constraint set point P4, and the pressure plate clamping force constraint set point P5 to realize the equivalent conversion of concentrated load and distributed load, simplify the complex contact boundary conditions, and improve the calculation efficiency. By superimposing and displaying the temperature distribution nephogram and the extreme values of axial displacement, the correlation between the high-temperature region and the maximum deformation region is analyzed. By respectively extracting the axial displacement amounts on the inner and outer sides of the friction surface of the pressure plate, the thermo-mechanical coupling deformation amount of the pressure plate is identified, solving the problems of low accuracy, narrow working condition coverage, and poor result practicability in the thermal deformation simulation of the clutch pressure plate. Description of the Drawings

[0018] To more clearly illustrate the technical solutions of the present invention, the accompanying drawings required in the description will be briefly introduced below. Obviously, the accompanying drawings in the following description are only some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other accompanying drawings can be obtained based on these drawings.

[0019] Figure 1 It is a flow chart of the clutch pressure plate thermal deformation simulation method; Figure 2 It is a schematic diagram of one side of the three-dimensional model of the dry diaphragm spring clutch pressure plate; Figure 3 It is a schematic diagram of the other side of the three-dimensional model of the dry diaphragm spring clutch pressure plate; Figure 4 It is a schematic diagram of the finite element model of the clutch thermo-mechanical coupling deformation; Figure 5 It is a schematic diagram of the three-dimensional model of the driven plate assembly; Figure 6 It is a schematic diagram of the three-dimensional model of the flywheel; Figure 7 It is a schematic diagram of setting the constraint set points on the outer side of the flywheel; Figure 8 It is a schematic diagram of setting the constraint set points on the inner side of the flywheel; Figure 9 It is a schematic diagram of setting the constraint set points of the large steel sheet; Figure 10 It is a schematic diagram of setting the constraint set points of the pressure plate; Figure 11 It is a schematic diagram of setting the constraint set points of the pressure plate clamping force; Figure 12 It is a schematic diagram of the electronic device. Specific embodiments

[0020] The clutch pressure plate thermal deformation simulation method provided in this application performs simulation based on the thermal deformation of the dry diaphragm spring clutch pressure plate. This application first obtains the three-dimensional models of the clutch-related components and establishes a finite element model of the pressure plate temperature field; then based on these three-dimensional models, a finite element model of the clutch thermo-mechanical coupling deformation is established and constraint points are set; subsequently, relevant parameters are determined according to the operating conditions, and the heat flux density of the pressure plate friction surface is calculated; then, the simulation results of the pressure plate thermo-mechanical coupling deformation are calculated using the heat flux density and the temperature field model, and at the same time, the thermal deformation amount of the pressure plate is calculated through the thermo-mechanical coupling deformation model and the result file is output; finally, the simulation results are configured into the temperature distribution cloud map, the maximum and minimum values of the axial displacement are displayed, and the axial displacement amounts on the inner and outer sides of the friction surface are extracted to obtain the thermo-mechanical coupling deformation amount of the pressure plate.

[0021] Through the system's modeling and calculation process, this application can simulate the thermal deformation of the pressure plate of a dry diaphragm spring clutch, providing quantitative simulation data support for the design optimization of the clutch.

[0022] The following will describe in detail the specific process of the thermal deformation simulation method of the clutch pressure plate. For the purpose of illustration rather than limitation, specific details such as specific system structures and technologies are proposed to thoroughly understand the embodiments of this application. However, those skilled in the art should clearly understand that this application can also be implemented in other embodiments without these specific details.

[0023] Statements such as "an embodiment" or "some embodiments" described in this application mean that specific features, structures, or characteristics described in that embodiment are included in one or more embodiments of this application. Thus, statements such as "in one embodiment", "in some embodiments", "in other some embodiments", "in still other embodiments" that appear in different places in this application do not necessarily refer to the same embodiment, but mean "one or more but not all embodiments", unless otherwise specifically emphasized in other ways.

[0024] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0025] Please refer to Figure 1 The following is a flowchart of the thermal-mechanical coupling deformation simulation method of the clutch pressure plate in a specific embodiment. The method includes: S101: Obtain the three-dimensional models of the pressure plate, driven plate assembly, and flywheel of the dry diaphragm spring clutch, and establish a finite element model of the pressure plate temperature field.

[0026] For this embodiment, the three-dimensional models of the pressure plate, driven plate assembly, and flywheel of the dry diaphragm spring clutch can be constructed based on, for example, SolidWorks or UG. Optionally, the three-dimensional model of the driven plate assembly of the dry diaphragm spring clutch can be configured based on the three-dimensional model of the friction plate, wave washer, and large steel sheet; or configured through the three-dimensional model of the friction plate and the wave large steel sheet.

[0027] As shown in the appendix Figure 2 and Figure 3Shown is the three-dimensional model of the pressure plate of a dry diaphragm spring clutch, and a finite element model of the temperature field of the pressure plate is established. The three-dimensional model of the pressure plate is imported into the finite element analysis software. By defining material parameters such as thermal conductivity and specific heat capacity, and dividing the mesh, a finite element model of the temperature field of the pressure plate is established.

[0028] It should be noted that in this embodiment, modeling can be carried out in three-dimensional modeling software according to design drawings or actual measured dimensions. In the finite element analysis software, material parameters are set according to the material property manual, and mapped mesh division is used to generate the mesh. In this way, the temperature distribution of the pressure plate during the working process can be accurately simulated, which is convenient for understanding the root cause and distribution law of frictional heat generation.

[0029] S102: Based on the obtained three-dimensional models of the pressure plate of the dry diaphragm spring clutch, the three-dimensional model of the driven plate assembly, and the three-dimensional model of the flywheel, a finite element model of the thermo-mechanical coupling deformation of the clutch is established, and constraint set points are set at preset positions.

[0030] In this embodiment, a finite element model of the thermo-mechanical coupling deformation of the clutch is established based on the obtained three-dimensional models of the pressure plate of the dry diaphragm spring clutch, the three-dimensional model of the driven plate assembly, and the three-dimensional model of the flywheel.

[0031] In this embodiment, the three-dimensional models of the pressure plate, the driven plate assembly, and the flywheel are assembled in the finite element analysis software to establish a finite element model of the thermo-mechanical coupling deformation of the clutch. According to the actual working constraint conditions of the clutch, constraint set points are set at preset positions, such as the connection part between the flywheel and the engine, the connection part between the pressure plate and the clutch cover, etc., to simulate the actual constraint situation.

[0032] Such as Figure 4 is a schematic diagram of the finite element model of the thermo-mechanical coupling deformation of the clutch, such as Figure 5 is a schematic diagram of the three-dimensional model of the driven plate assembly, such as Figure 6 is a schematic diagram of the three-dimensional model of the flywheel. The finite element model of the thermo-mechanical coupling deformation of the clutch established in this embodiment includes the outer constraint set point P1 of the flywheel, the inner constraint set point P2 of the flywheel, the constraint set point P3 of the large steel sheet, the constraint set point P4 of the pressure plate, and the constraint set point P5 of the pressure plate clamping force, specifically as Figures 7 to 11 shown.

[0033] It should be noted that in the established finite element model of the thermo-mechanical coupling deformation of the clutch, a contact constraint (Contant Pair constraint) is established between the pressure plate and the friction plate, a contact constraint (Contant Pair constraint) is established between the flywheel and the friction plate, and a binding constraint (Tie constraint) is established between the contact surfaces of the friction plate, the wave washer, and the large steel sheet (friction plate, wave large steel sheet).

[0034] In this embodiment, model assembly is carried out in finite element software. By using the constraint definition function, constraint set points are set at specified positions to restrict the corresponding degrees of freedom, such as translational and rotational degrees of freedom. In this way, establishing an accurate finite element model of thermo-mechanical coupling deformation and reasonably setting the constraint set points can truly simulate the mechanical and heat transfer interactions of the clutch during operation, making the simulation results closer to the actual working conditions.

[0035] For this embodiment, in the established finite element model of thermo-mechanical coupling deformation of the clutch and the finite element model of the pressure plate temperature field, the material property parameters of each part need to be input. Exemplarily, the material property parameters of the pressure plate include: thermal conductivity, specific heat capacity, density, elastic modulus, Poisson's ratio, and coefficient of thermal expansion.

[0036] In the established finite element model of thermo-mechanical coupling deformation of the clutch in this embodiment, the mesh types of at least the pressure plate and the upper friction plate can be set as second-order meshes, and the mesh types of the remaining parts are set as first-order meshes. In the established finite element model of the pressure plate temperature field, the mesh type of the pressure plate is set as a second-order mesh to meet the requirements of simulation calculation.

[0037] S103: Based on the operating conditions of the dry diaphragm spring clutch, determine the contact pressure p, rotational speed n, engagement time t1, and friction coefficient μ of the friction surface of the clutch pressure plate, and calculate the heat flux density ψ applied to the friction surface of the pressure plate.

[0038] In this embodiment, based on actual working condition tests or referring to relevant industry standards, parameters such as the contact pressure p, rotational speed n, engagement time t1, and friction coefficient μ of the dry diaphragm spring clutch in different working scenarios can be determined. Then, using the heat flux density ψ calculation formula, the heat flux density ψ applied to the friction surface of the pressure plate is calculated.

[0039] The calculation formula for the heat flux density ψ is: ψ = p × n × t1 × μ.

[0040] In this way, this embodiment can calculate the heat flux density, thereby being able to determine the heat load borne by the pressure plate during operation and providing data for the calculation of thermo-mechanical coupling deformation.

[0041] S104: Based on the heat flux density and the finite element model of the pressure plate temperature field, calculate the simulation results of the thermo-mechanical coupling deformation of the pressure plate under different analysis step temperature fields.

[0042] In this embodiment, the calculated heat flux density is applied as a load to the finite element model of the pressure plate temperature field. Different analysis steps are set in the finite element analysis software to simulate the temperature change process of the pressure plate at different times or under different working conditions. The simulation results of the thermo-mechanical coupling deformation of the pressure plate under different analysis step temperature fields are obtained through heat conduction calculation.

[0043] In this embodiment, when defining the heat flux density load, analysis step parameters such as time step size and analysis type can be set, and then the thermal analysis calculation is started to obtain the temperature field distribution and the results of thermo-mechanical coupling deformation. In this way, the thermo-mechanical coupling deformation of the pressure plate under different working conditions can be simulated.

[0044] S105: Based on the finite element model of the clutch thermo-mechanical coupling deformation, calculate the thermal deformation of the pressure plate at different analysis steps, and output the calculation results as a simulation result file.

[0045] In this embodiment, based on the established finite element model of the clutch thermo-mechanical coupling deformation, different analysis steps can be set in the finite element analysis software to calculate the thermal deformation of the pressure plate at each analysis step. The calculated thermal deformation data is sorted and output to generate a simulation result file. The simulation result file can be a text file, a chart file, etc.

[0046] S106: Configure the simulation results of the pressure plate thermo-mechanical coupling deformation to the temperature distribution nephogram of the pressure plate, display the maximum and minimum values of the axial displacement in the temperature distribution nephogram, respectively extract the axial displacement amounts on the inner and outer sides of the friction surface of the pressure plate at the analysis step, and calculate the thermo-mechanical coupling deformation amount of the pressure plate.

[0047] In this embodiment, the simulation results of the pressure plate thermo-mechanical coupling deformation can be imported into the post-processing module of the finite element analysis software and configured with the temperature distribution nephogram of the pressure plate. The maximum and minimum values of the axial displacement are displayed in the temperature distribution nephogram. The axial displacement amounts on the inner and outer sides of the friction surface of the pressure plate at the analysis step are respectively extracted through the post-processing tool, and finally the thermo-mechanical coupling deformation amount of the pressure plate is calculated according to the extracted data. In this way, the thermo-mechanical coupling deformation can be intuitively displayed in the temperature distribution nephogram, which is convenient for users to understand the relationship between the deformation characteristics of the pressure plate and the temperature distribution, and provides a reference basis for the optimization design and performance evaluation of the clutch.

[0048] Based on the above embodiments, in order to further improve the reliability and simulation effectiveness of the clutch pressure plate thermal deformation simulation method provided in the above embodiments, the following is an implementable manner. In this embodiment, based on the calculated heat flux density and the finite element model of the pressure plate temperature field, the calculation steps of the pressure plate thermal deformation are as follows: Step S201: Apply the heat flux density calculated according to the above heat flux density ψ calculation formula to the friction surface of the pressure plate within the engagement time t1, and the process of applying the heat flux density is linearly increasing or linearly decreasing.

[0049] In this embodiment, during the time period t1 when the clutch is engaged, the heat flux density value can be calculated according to the previously obtained calculation formula of the heat flux density ψ, and the heat flux density is loaded onto the friction surface of the pressure plate. The process of applying the heat flux density exhibits the characteristics of linear increase or linear decay, so as to simulate the change of heat flux generation during the actual clutch engagement process.

[0050] Step S202: No heat flux density is applied during the heat transfer time t2, and only heat transfer occurs inside the pressure plate.

[0051] In this embodiment, a heat transfer analysis step with a time length of t2 can be set. According to the temperature field result obtained in step S201, the temperature distribution inside the pressure plate can be obtained through Fourier's law.

[0052] Step S203: Repeat calculation step S201 and calculation step S202 until the temperature of the pressure plate rises from the initial temperature to the specified temperature, and obtain the simulation results of the temperature field distribution of the pressure plate under different analysis steps. The initial temperature can be set to 20 °C or 70 °C. The specified temperature after rising can be 200 °C or 300 °C.

[0053] The execution method here can set the initial temperature and the specified temperature. Use a loop execution program to sequentially execute step S201 and step S202 in each loop. After each loop ends, check whether the maximum temperature or the average temperature of the pressure plate reaches the specified temperature. If it does not reach, continue the loop; if it reaches, stop the loop and save the temperature field distribution results under different analysis steps.

[0054] Optionally, the initial temperature of the pressure plate can be set to 20 °C or 70 °C. The specified temperature to which it rises is 200 °C or 300 °C. The following calculates the thermal deformation amount of the pressure plate through step S204 based on the clutch thermo-mechanical coupling deformation finite element model.

[0055] Step S204: Apply a specified pre-compression force in the axial direction of the pressure plate clamping force constraint set point P5. The pre-compression force can be set to 100 N to establish pre-contact between the pressure plate and the friction plate, and between the friction plate and the flywheel.

[0056] Step S205: Apply a specified diaphragm spring clamping force in the axial direction of the pressure plate clamping force constraint set point P5.

[0057] Step S206: Apply a specified engine torque in the axial rotation direction of the flywheel inner side constraint set point P2 and the pressure plate constraint set point P4 respectively.

[0058] It should be noted that at the inner flywheel constraint set point P2 and the pressure plate constraint set point P4, engine torque is applied in the axial rotation direction to simulate the situation where the power output by the engine is transmitted to the clutch. Clutches of different models are adapted to different magnitudes of engine torque, so the torque magnitude needs to be determined according to specific circumstances.

[0059] In this embodiment, the engine torque magnitude can be determined according to the specific clutch model. At the inner flywheel constraint set point P2 and the pressure plate constraint set point P4 respectively, the degrees of freedom of axial rotation are defined and the corresponding magnitude of engine torque is applied.

[0060] Among them, the magnitudes of the loads applied in calculation steps S5 and S6 are different for dry diaphragm spring clutches adapted to different engine torque magnitudes and need to be determined according to the specific clutch model.

[0061] Step S207: Read the pressure plate temperature fields of all or some of the analysis steps generated in calculation steps S201 to S203, and input them one by one into the calculation results after loading the mechanical load in the clutch thermo-mechanical coupling deformation finite element model to calculate and obtain the pressure plate thermo-mechanical coupling deformation simulation results under the temperature fields of different analysis steps.

[0062] It should be noted that in steps S204 and S205, the constraint set point P1 and the constraint set point P2 are set to constrain all degrees of freedom. For the convenience of explanation, all degrees of freedom refer to 6 degrees of freedom, that is, it is defined that degree of freedom one, degree of freedom two, and degree of freedom three respectively represent the translational degrees of freedom of the set point along the x, y, and z axes; degree of freedom four, degree of freedom five, and degree of freedom six respectively represent the rotational degrees of freedom of the set point around the x, y, and z axes.

[0063] In this embodiment, the constraint set points P3 and P4 of the present embodiment constrain the other five degrees of freedom except axial translation.

[0064] In step S206, the other five degrees of freedom of the constraint set points P1 and P2 except for axial rotation are constrained, the other five degrees of freedom of the constraint set point P3 except for axial translation are constrained, and the other four degrees of freedom of the constraint set point P4 except for axial translation and axial rotation are constrained.

[0065] It should be noted that in this embodiment, in a finite element calculation software, a finite element model of the pressure plate temperature field and a finite element model of the clutch thermal-mechanical coupling deformation can be established, a three-dimensional mesh model can be imported, constraint set points P1 to P5 can be established, contact surfaces can be selected, contact and binding constraints can be established, material property parameters can be input, a calculation analysis step can be established, constraints and loads can be set in each analysis step, the finite element model of the pressure plate temperature field can be calculated according to steps S201 to S203 to obtain the calculation results of the pressure plate temperature field at different analysis steps, and then the finite element model of the clutch thermal-mechanical coupling deformation can be calculated according to steps S204 to S207 to obtain the calculation results of the thermal deformation amount of the pressure plate at different analysis steps. After the calculation is completed, a simulation result file is output.

[0066] The steps of configuring material property parameters and setting constraints and loads in this embodiment further include: defining that the contact constraint between the pressure plate and the friction plate, and the contact constraint between the flywheel and the friction plate, and establishing a binding constraint between the contact surfaces of the friction plate, the wave washer, and the large steel plate; setting material properties based on elastic modulus, Poisson's ratio, density, coefficient of thermal expansion, and thermal conductivity; setting the time increment of the analysis step to 10 s, or 20 s, or 50 s; defining the loading methods of the analysis step including: pressing force, torque, and temperature field.

[0067] It can be seen that the method of this embodiment can accurately predict the thermal deformation of the pressure plate by accurately simulating the heat transfer and mechanical load effects during the actual working process of the clutch. The influence of thermal deformation on the clutch performance can be fully considered in the design stage, the structure and material selection of the clutch can be optimized, and the reliability of the clutch can be improved. By analyzing the thermal deformation of the pressure plate, the influence of thermal deformation on performance indicators such as the torque transmission capacity, friction plate wear, and separation characteristics of the clutch can be understood. Based on the analysis results, the working parameters and structure of the clutch can be optimized to improve the comprehensive performance of the clutch.

[0068] This embodiment can, based on the simulation result file obtained in step S203, retrieve the temperature distribution contour map of the pressure plate, display the maximum temperature in the map, and extract the highest temperature of the pressure plate friction surface at a specified analysis step.

[0069] For this embodiment, the method for extracting the thermal-mechanical coupling deformation amount of the pressure plate is based on the simulation result file obtained in step S207, retrieve the displacement distribution contour map in the axial direction of the pressure plate friction surface, display the maximum and minimum values of the axial displacement in the displacement distribution contour map, and respectively extract the axial displacement amounts of the inner side, which can be the minimum value, and the outer side, which can be the maximum value, of the pressure plate friction surface at a specified analysis step. Subtract the axial displacement amount of the outer side of the pressure plate friction surface from the axial displacement amount of the inner side of the pressure plate friction surface to obtain the thermal-mechanical coupling deformation amount of the pressure plate.

[0070] As an embodiment of the present application, a heat flux density that varies linearly with time can be applied to the pressure plate friction surface ; where \(t\leq t_{}\) P ; \(t\) is used to describe the time in the whole heat conduction process.

[0071] Based on the process of heat diffusing from the high - temperature region to the low - temperature region inside the pressure plate material, etc., the change of the temperature inside the pressure plate with time and space within a preset time period is obtained through the following transient heat conduction calculation formula.

[0072] The transient heat conduction calculation formula is: ; \(\rho\) is the density, \(c_p\) is the specific heat capacity, \(T\) represents temperature, which is the temperature value at a certain point in three - dimensional space at a certain moment. Repeat the above process until the temperature of the pressure plate reaches the preset target value.

[0073] In the method, a pre - contact axial force of 100 N is applied at the pressure plate clamping force constraint set point \(P5\); the dynamic diaphragm spring clamping force is input according to the clutch model.

[0074] Torques \(N_B = F\cdot r\) around the axial direction are applied at the flywheel inner side constraint set point \(P2\) and the pressure plate constraint set point \(P4\); Map the temperature field results to the mechanical model, and calculate the stress of the thermo - elastic material when stressed and temperature - changed through the following formula to obtain the coupling effect of thermal expansion and mechanical stress.

[0075] ; where \(C\) is the elastic stiffness matrix, \(\varepsilon\) is the strain, \(\alpha\) is the coefficient of thermal expansion, \(I\) is the unit tensor; Based on the output of the pressure plate axial displacement nephogram, calculate the thermal deformation amount \(B_q\) as: \(B_q = B_1 + B_2\); \(B_1\) is the deformation amount generated under the action of mechanical stresses such as the diaphragm spring clamping force and engine torque; \(B_2\) is the deformation amount generated by thermal expansion.

[0076] It can be seen that in this embodiment, the simulation result file obtained by combining the above calculation process with steps S206 and S207 is used. The result of step S207 is subtracted from the result of step S206, and then the displacement distribution nephogram in the axial direction of the pressure plate friction surface is retrieved. The maximum and minimum values of the axial displacement are displayed in the figure, and the axial displacement amounts on the inner and outer sides of the pressure plate friction surface at the specified analysis step are extracted respectively. The axial displacement amount on the inner side of the pressure plate friction surface is subtracted from the axial displacement amount on the outer side of the pressure plate friction surface to obtain the thermal deformation amount of the pressure plate. In this way, the mechanical behavior of the material under the combined action of heat and mechanical loads can be accurately described during the thermal-mechanical coupling solution process. The thermal expansion effect caused by temperature change is coupled with the mechanical stress, so as to simulate the stress and deformation conditions of the pressure plate during actual operation, improving the accuracy of the simulation results. Moreover, during the calculation process, multiple aspects such as heat flux density application, heat conduction solution, mechanical load application, and thermal-mechanical coupling are comprehensively considered, which can accurately reflect the actual working conditions of the clutch and meet the design and optimization requirements of the clutch.

[0077] It should be understood that the magnitudes of the sequence numbers of the steps in the above embodiments do not mean the order of execution is prior or subsequent. The execution order of each process should be determined according to its function and internal logic, and should not constitute any limitation to the implementation process of the embodiments of the present invention.

[0078] The following are embodiments of the clutch pressure plate thermal deformation simulation system provided by the embodiments of the present disclosure. This system and the clutch pressure plate thermal deformation simulation method of the above embodiments belong to the same inventive concept. For the details not described in detail in the embodiments of the clutch pressure plate thermal deformation simulation system, reference can be made to the embodiments of the clutch pressure plate thermal deformation simulation method.

[0079] The system includes: A pressure plate temperature field model establishment module, configured to obtain three-dimensional models of the pressure plate, driven plate assembly, and flywheel of a dry diaphragm spring clutch, and establish a finite element model of the pressure plate temperature field.

[0080] A constraint set point configuration module, configured to establish a finite element model of clutch thermal-mechanical coupling deformation based on the three-dimensional models of the pressure plate, driven plate assembly, and flywheel of the dry diaphragm spring clutch obtained, and set constraint set points at preset positions.

[0081] A parameter calculation module, configured to determine the contact pressure p, rotational speed n, engagement time t1, and friction coefficient μ of the clutch pressure plate friction surface in combination with the service conditions of the dry diaphragm spring clutch, and calculate the heat flux density ψ applied to the pressure plate friction surface.

[0082] A simulation parameter calculation module, configured to calculate the simulation results of the thermal-mechanical coupling deformation of the pressure plate under different analysis step temperature fields in combination with the heat flux density and the finite element model of the pressure plate temperature field.

[0083] A simulation processing module, which is used to calculate the thermal deformation amount of the pressure plate at different analysis steps in combination with the finite element model of the clutch thermal-mechanical coupling deformation, and output the calculation result as a simulation result file.

[0084] A deformation amount calculation module, which is used to configure the simulation result of the thermal-mechanical coupling deformation of the pressure plate into the temperature distribution nephogram of the pressure plate, display the maximum and minimum values of the axial displacement in the temperature distribution nephogram, respectively extract the axial displacement amounts on the inner and outer sides of the friction surface of the pressure plate at the analysis step, and calculate the thermal-mechanical coupling deformation amount of the pressure plate.

[0085] As Figure 12 shown, the present application also provides an electronic device, including a display module 103, a memory 102, a processor 101, and a computer program stored on the memory and executable on the processor 101. When the processor 101 executes the program, the steps of the clutch pressure plate thermal deformation simulation method are implemented.

[0086] In the embodiments of the present invention, the electronic device includes, but is not limited to, a laptop computer, a desktop computer, a workbench, a personal digital assistant, a server, a blade server, a mainframe computer, and other suitable computers. The electronic device can also represent various forms of mobile devices, such as personal digital processing, cellular phones, smart phones, wearable devices, and other similar computing devices. The components shown herein, their connections and relationships, and their functions are merely examples and are not intended to limit the implementation of the embodiments of the present application described herein and / or claimed.

[0087] In the embodiments of the present application, the processor 101 can be implemented by using at least one of an application specific integrated circuit (ASIC), a programmable logic device (PLD), a field programmable gate array (FPGA), a processor, a controller, a microcontroller, a microprocessor, and an electronic unit designed to execute the functions described herein. In some cases, such an implementation can be implemented in the controller. For a software implementation, an implementation of a process or function can be implemented with a separate software module that allows execution of at least one function or operation. The software code can be implemented by a software application (or program) written in any suitable programming language. The software code can be stored in the memory and executed by the controller.

[0088] The display module 103 is used to display the information input by the user or the information provided to the user. The display module 103 may include a display panel, and the display panel can be configured in the form of a liquid crystal display (LCD), an organic light-emitting diode (OLED), etc.

[0089] The memory 102 can be used to store software programs and various data. The memory 102 may include a high-speed random access memory, and may also include a non-volatile memory, such as at least one magnetic disk storage device, a flash memory device, or other volatile solid-state storage devices.

[0090] This application also provides a storage medium, on which a computer program is stored. When the computer program is executed by a processor, the steps of the clutch pressure plate thermal deformation simulation method are implemented.

[0091] The storage medium can adopt any combination of one or more readable media. The readable media can be a readable signal medium or a readable storage medium. The readable storage medium can be, for example but not limited to, an electrical, magnetic, optical, electromagnetic, infrared, or semiconductor system, apparatus, or device, or any combination of the above. More specific examples (non-exhaustive list) of the readable storage medium include: an electrical connection having one or more wires, a portable disk, a hard disk, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or flash memory), an optical fiber, a portable compact disk read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination of the above.

[0092] The above description of the disclosed embodiments enables those skilled in the art to implement or use the present invention. Various modifications to these embodiments will be obvious to those skilled in the art, and the general principles defined herein can be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention will not be limited to these embodiments shown herein, but will be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A method for simulating the thermal deformation of a clutch pressure plate, characterized in that the method Including: Obtain the three-dimensional models of the pressure plate, driven disc assembly, and flywheel of the dry diaphragm spring clutch, and establish a finite element model of the pressure plate temperature field; Based on the obtained three-dimensional models of the pressure plate, driven disc assembly, and flywheel of the dry diaphragm spring clutch, establish a finite element model of the thermo-mechanical coupling deformation of the clutch, and set constraint set points at preset positions; Based on the operating conditions of the dry diaphragm spring clutch, determine the contact pressure p, rotational speed n, engagement time t1, and friction coefficient μ of the friction surface of the clutch pressure plate, and calculate the heat flux density ψ applied to the friction surface of the pressure plate; Based on the heat flux density and the finite element model of the pressure plate temperature field, calculate the simulation results of the thermo-mechanical coupling deformation of the pressure plate under different analysis step temperature fields; Based on the finite element model of the thermo-mechanical coupling deformation of the clutch, calculate the thermal deformation of the pressure plate at different analysis steps, and output the calculation results as a simulation result file; Configure the simulation results of the thermo-mechanical coupling deformation of the pressure plate into the temperature distribution contour map of the pressure plate, display the maximum and minimum values of the axial displacement in the temperature distribution contour map, respectively extract the axial displacement amounts on the inner and outer sides of the friction surface of the pressure plate at the analysis step, and calculate the thermo-mechanical coupling deformation amount of the pressure plate.

2. The method for simulating the thermal deformation of the clutch pressure plate according to claim 1, wherein: The calculation formula for the heat flux density ψ is: ψ = p × n × t1 × μ.

3. The method for simulating the thermal deformation of the clutch pressure plate according to claim 1 or 2, wherein: The manner of calculating the simulation results of the thermo-mechanical coupling deformation of the pressure plate under different analysis step temperature fields in step includes: Step S201: Apply the calculated heat flux density to the friction surface of the pressure plate within the engagement time t1; Step S202: Do not apply heat flux density within the heat transfer time t2, and only perform heat transfer inside the pressure plate; Step S203: Repeat calculation steps S201 and S202 until the temperature of the pressure plate rises from the initial temperature to the preset temperature, and obtain the simulation results of the temperature field distribution of the pressure plate at different analysis steps.

4. The method for simulating the thermal deformation of the clutch pressure plate according to claim 3, wherein: The step of calculating the thermal deformation of the pressure plate at different analysis steps based on the finite element model of the thermo-mechanical coupling deformation of the clutch and outputting the calculation results as a simulation result file further includes: Step S204: Apply a specified pre-compression force in the axial direction of the pressure plate clamping force constraint set point P5 to establish pre-contact between the pressure plate and the friction plate and between the friction plate and the flywheel; Step S205: Apply a specified diaphragm spring clamping force in the axial direction of the pressure plate clamping force constraint set point P5; Step S206: Apply a preset engine torque in the axial rotation direction to the inner constraint set point P2 of the flywheel and the pressure plate constraint set point P4 respectively; Step S207: Read the temperature fields of the pressure plate generated in steps S201 to S203 in all or some analysis steps, and input them one by one into step S206 after loading the mechanical load in the finite element model of the thermo-mechanical coupling deformation of the clutch to obtain the simulation results of the thermo-mechanical coupling deformation of the pressure plate under different analysis step temperature fields.

5. The method for simulating the thermal deformation of the clutch pressure plate according to claim 4, wherein: In the method, the outer flywheel constraint set point P1, the inner flywheel constraint set point P2, the large steel sheet constraint set point P3, the pressure plate constraint set point P4, and the pressure plate clamping force constraint set point P5 are respectively defined; Set the outer flywheel constraint set point P1 and the inner flywheel constraint set point P2 as full-degree-of-freedom constraints, and set the large steel sheet constraint set point P3 as the other five degrees of freedom constraints except axial translation; Set the pressure plate constraint set point P4 as the other four degrees of freedom constraints except axial translation and rotation about the axis; Establish contact constraints between the pressure plate and the friction plate, and between the flywheel and the friction plate, and establish binding constraints between the friction plate, the wave washer, and the large steel sheet; Configure the material property parameters, set the constraints and loads, and calculate the finite element model of the pressure plate temperature field according to steps S201 to S203 to obtain the calculation result of the pressure plate temperature field; Calculate the finite element model of the clutch thermo-mechanical coupling deformation according to steps S204 to S207 to obtain the calculation result of the pressure plate thermal deformation; Configure the calculation result of the pressure plate temperature field and the calculation result of the pressure plate thermal deformation as a simulation result file; Retrieve the displacement distribution nephogram in the axial direction of the pressure plate friction surface, display the maximum and minimum values of the axial displacement in the figure, and extract the axial displacement amounts on the inner and outer sides of the pressure plate friction surface respectively; Subtract the axial displacement amount on the outer side of the pressure plate friction surface from the axial displacement amount on the inner side of the pressure plate friction surface to obtain the thermo-mechanical coupling deformation amount of the pressure plate.

6. The clutch pressure plate thermal deformation simulation method according to claim 5, characterized in that The step of configuring the material property parameters and setting the constraints and loads further includes: Define the contact constraint between the pressure plate and the friction plate, the contact constraint between the flywheel and the friction plate, and establish a binding constraint between the contact surfaces of the friction plate, the wave washer, and the large steel sheet; Set the material properties based on elastic modulus, Poisson's ratio, density, thermal expansion coefficient, and thermal conductivity; Set the time increment of the analysis step to 10s, or 20s, or 50s; Define the loading methods of the analysis step including: diaphragm spring clamping force, torque, and temperature field.

7. The clutch pressure plate thermal deformation simulation method according to claim 5, characterized in that The method further includes: applying a heat flux density that linearly changes with time to the friction surface of the pressure plate ; , where t ≤ t P ; t is used to describe the time in the whole heat conduction process; Based on the process of heat diffusion from the high-temperature region to the low-temperature region inside the pressure plate material, the change of the temperature inside the pressure plate with time and space within a preset time period is obtained through the following transient heat conduction calculation formula; The transient heat conduction calculation formula is as follows: ; is the density, is the specific heat capacity, and T represents the temperature, indicating the temperature value at a certain point in three-dimensional space at a certain moment; Repeat the above process until the pressure plate temperature reaches the preset target value; In the method, a pre-contact axial force of 100N is applied at the pressure plate clamping force constraint set point P5; Input the dynamic diaphragm spring clamping force according to the clutch model; Apply a torque NB = F·r about the axis at the inner flywheel constraint set point P2 and the pressure plate constraint set point P4; Map the temperature field results to the mechanical model and calculate the stress of the thermoelastic material under force and temperature change through the following formula , and obtain the coupling effect of thermal expansion and mechanical stress; ； where C is the elastic stiffness matrix, is the strain, is the coefficient of thermal expansion, and I is the unit tensor; Based on the output axial displacement nephogram of the pressure plate, calculate the thermal deformation amount Bq as: Bq = B1 + B2; B1 is the deformation amount generated under the action of mechanical stresses such as diaphragm spring clamping force and engine torque; B2 is the deformation amount generated by thermal expansion.

8. A clutch pressure plate thermal deformation simulation system, characterized in that, The system is used to implement the clutch pressure plate thermal deformation simulation method according to any one of claims 1 to 7; The system includes: The pressure plate temperature field model establishment module is used to obtain the three-dimensional models of the pressure plate, the driven plate assembly, and the flywheel of the dry diaphragm spring clutch, and establish a finite element model of the pressure plate temperature field; The constraint set point configuration module is used to establish a finite element model of the clutch thermo-mechanical coupling deformation based on the three-dimensional models of the pressure plate, the driven plate assembly, and the flywheel of the dry diaphragm spring clutch obtained, and set constraint set points at preset positions; The parameter calculation module is used to determine the contact pressure p, rotational speed n, engagement time t1, and friction coefficient μ of the friction surface of the clutch pressure plate in combination with the operating conditions of the dry diaphragm spring clutch, and calculate the heat flux density ψ applied to the friction surface of the pressure plate; The simulation parameter calculation module is used to calculate the simulation results of the thermo-mechanical coupling deformation of the pressure plate under the temperature field of different analysis steps in combination with the heat flux density and the finite element model of the pressure plate temperature field; The simulation processing module is used to calculate the thermal deformation amount of the pressure plate at different analysis steps in combination with the finite element model of the clutch thermo-mechanical coupling deformation, and output the calculation results as a simulation result file; The deformation amount calculation module is used to configure the simulation results of the thermo-mechanical coupling deformation of the pressure plate to the temperature distribution cloud map of the pressure plate, display the maximum and minimum values of the axial displacement in the temperature distribution cloud map, respectively extract the axial displacement amounts on the inner and outer sides of the friction surface of the pressure plate at the analysis step, and calculate the thermo-mechanical coupling deformation amount of the pressure plate.

9. An electronic device, comprising a memory, a processor, and a computer program stored on the memory and executable on the processor, wherein When the processor executes the program, it implements the steps of the clutch pressure plate thermal deformation simulation method according to any one of claims 1 to 7.

10. A storage medium having a computer program stored thereon, characterized in that, When the computer program is executed by the processor, it implements the steps of the clutch pressure plate thermal deformation simulation method according to any one of claims 1 to 7.

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