Clutch friction plate groove shape optimization method, device, equipment and medium

Abstract

The invention provides a clutch friction plate groove shape optimization method, device, equipment and medium, belongs to the technical field of clutch friction plates, and simulates the surface temperature field and stress field distribution of a wet clutch friction pair based on fluid thermosetting coupling simulation; friction heat is simulated through heat-engine coupling of the static simulation module, and the heat is transmitted to the fluid simulation module; convective heat transfer is simulated by utilizing flow-heat coupling of the fluid simulation module, and heat flux is transferred to the statics simulation module; the fluid thermosetting coupling calculation is realized circularly and repeatedly, the influence of different groove shapes on the clutch is analyzed according to the temperature information, the strength information and the heat exchange information, the most appropriate groove shape is selected, and the working performance and reliability of the clutch are improved.

Description

Technical Field

[0001] The present invention belongs to the technical field of clutch friction plates, and in particular relates to a clutch friction plate groove shape optimization method, device, equipment and medium. Background Art

[0002] Wet clutches are widely used in automatic transmissions. Wet clutches include friction plates (consisting of friction base plates and friction paper bases), dual steel plates, inner hubs, outer hubs, retaining rings or baffles, and pistons. In the related art, wet clutches produce friction and a large amount of heat during the gear shifting and engagement process of the transmission, resulting in excessive instantaneous temperature rise of the friction pair, excessive surface temperature and stress gradients, and thus local hot spots on the friction plates or steel plates, surface ablation, warping and other faults. In particular, wet clutches in automatic transmissions for high-torque commercial vehicles are prone to local hot spots on the friction plates or steel plates, surface ablation, warping and other faults due to the large torque they carry.

[0003] In the related art, the shape of the clutch friction plate groove is simulated and then selected. However, the related art only considers the simulation of solid heat conduction, which will underestimate or overestimate the temperature change near the friction plate groove caused by the flow of lubricating oil to carry away heat. It is impossible to determine the area where the temperature is too high, resulting in problems such as degradation of friction plate material performance and lubricating oil failure due to overheating. Moreover, in the related art, statics simulation software and fluid simulation software are used independently to simulate and analyze static and fluid related parameters. It is impossible to consider the mutual influence of physical processes such as friction heat generation, heat transfer between solids and fluids, and convective heat transfer, which affects the working stability and reliability of the clutch. Summary of the invention

[0004] The present invention provides a clutch friction plate groove shape optimization method. The present invention compares and analyzes the influence of different friction paper base groove types on the surface temperature field and stress field of the wet clutch friction pair, and then evaluates its temperature index and strength index, so as to provide a reference for the design of the friction plate groove shape of the wet clutch of the automatic transmission for commercial vehicles.

[0005] Methods include: S101: Simulate the temperature field and stress field distribution on the friction pair surface of the wet clutch based on the fluid-thermal-solid coupling simulation; S102: simulating friction heat by using the thermal-mechanical coupling of the statics simulation module, and transferring the heat to the fluid simulation module; S103: simulating convective heat transfer using the fluid-heat coupling of the fluid simulation module, and transferring the heat flux to the statics simulation module; S104: Repeatedly execute steps S102 and S103 to achieve fluid-thermal-solid coupling calculation, and analyze the influence of different groove shapes on the clutch based on temperature information, strength information, and heat transfer information, and select the groove shape.

[0006] Furthermore, it should be noted that the static simulation module performs mesh dissection on the wet clutch based on grid processing software; The dissection method of the friction substrate includes: cleaning the geometry to delete the fillets at the teeth, and performing topological segmentation on it using the friction paper substrate, and finally performing surface mesh and volume mesh division.

[0007] Furthermore, it should be noted that in the method, a thermal-solid coupling model is also built, the thermal-solid coupling model is imported into the static simulation module, and material parameters, interactions, and load boundaries are configured.

[0008] Furthermore, it should be noted that the material parameters include: density, specific heat capacity, thermal conductivity, thermal expansion rate, elastic modulus, and Poisson's ratio; The interactions and load boundaries include: the surfaces of the first part and the second part are used as interactions and load boundaries based on surface-to-surface binding, contact, and rigid connection; The interactions and load boundaries also include: the contact surfaces of the counter steel sheet and the outer hub and the surface of the snap ring are set in a fully constrained manner, the degrees of freedom of the piston center, the piston pressure at the piston center, and the sliding friction speed of the contact surface between the friction substrate and the inner hub are set.

[0009] Furthermore, it should be noted that in the method, a fluid-thermal coupling model is also built based on the fluid simulation module; Use grid processing software to perform mesh dissection on the groove basin of the wet clutch; Model based on the fluid simulation module and import the surface mesh; Modeling process and creating characteristic curves based on the fluid simulation module; Execute the modeling process using the fluid simulation module to convert the Part into a Region; Combine the modeling process of the fluid simulation module to perform mesh dissection, and perform secondary confirmation and optimization; Select the physical continuum model, and select a suitable physical continuum model from the physical model library of the fluid simulation module according to the actual properties, flow, and heat transfer states of the fluid in the clutch groove; Set the physical property parameters based on density, specific heat capacity, thermal conductivity, and dynamic viscosity, and configure them into the energy equation and momentum equation for solution; Set boundary conditions in the fluid simulation module for different boundaries of the groove basin; In the fluid simulation module, establish a rotational motion model and set the rotational speed parameter. If the operating speed of the clutch is constant, input a constant rotational speed value. If the speed varies with time or working conditions, write a mathematical expression according to the speed change law to simulate the motion state of the fluid in the groove driven by the rotating component under different working conditions, providing accurate initial flow conditions for subsequent fluid-thermal coupling calculations. Set the rotational motion boundary and the relative rotational speed relationship on the boundary to ensure that the shear force and velocity gradient generated by rotation can be correctly simulated when the fluid crosses the boundary, making the flow field calculation conform to the actual situation. Set the solution step size and convergence criterion.

[0010] It should be further noted that step S104 also includes: joint simulation of the statics simulation module and the fluid simulation module. Create a face set in the statics simulation module and store the coupled surfaces. Use the CAE interface of the statics simulation module to output the face set file and add keywords. Select additional physical models for the fluid domain. In the fluid simulation module, construct a physical model for the solid components of the clutch. In the fluid simulation module, import the face set file output by the statics simulation module with keywords, and use the keyword recognition function to quickly locate the three types of coupled surfaces. In the joint simulation settings interface of the fluid simulation module and the statics simulation module, determine the coupled variables transmitted between the two. In the joint simulation configuration module, set the interface of the statics simulation module for the docking interface with the fluid simulation module.

[0011] It should be further noted that the step of determining the coupled variables transmitted between the two also includes: For the pressure variable, set the output option in the fluid simulation module so that the pressure variable transmits the wall pressure data to the statics simulation module in real time. The statics simulation module sets the corresponding input interface at the receiving end, and applies the received pressure as an external load to the corresponding solid wall nodes to achieve mechanical coupling. For the heat flux variable, according to the principle of energy conservation, the convective heat transfer flux calculated by the fluid simulation module is transmitted to the statics simulation module, and the statics simulation module uses it as part of the thermal boundary condition to update the temperature field calculation of the solid components. The statics simulation module outputs the displacement information of the solid surface, and the fluid simulation module uses it to update the position of the fluid-solid coupling boundary after receiving it. The temperature information of the solid is transmitted to the fluid simulation module as the fluid thermophysical property calculation or the thermal boundary condition. Through the two-way setting of the coupling variables and their transmission mechanism, the combination of the statics and the fluid simulation module is realized.

[0012] The present application also provides a device for optimizing the groove shape of a clutch friction plate. The device includes: A simulation module that simulates the surface temperature field and stress field distribution of the wet clutch friction pair based on the fluid-thermal-solid coupling simulation; A statics simulation module for simulating frictional heat and transmitting the heat to the fluid simulation module; A fluid simulation module for simulating convective heat transfer and transmitting the heat flux to the statics simulation module; A cyclic selection module for realizing the fluid-thermal-solid coupling calculation and analyzing the influence of different groove shapes on the clutch based on the temperature information, strength information, and heat transfer information, and selecting the groove shape.

[0013] According to another embodiment of the present application, there is provided an electronic device 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 method for optimizing the groove shape of the clutch friction plate are implemented.

[0014] According to still another embodiment of the present application, there is also provided a storage medium having a computer program stored thereon. When the computer program is executed by a processor, the steps of the method for optimizing the groove shape of the clutch friction plate are implemented.

[0015] It can be seen from the above technical solutions that the present invention has the following advantages: The method for optimizing the groove shape of the clutch friction plate provided by the present application simulates the surface temperature field of the wet clutch friction pair through the fluid-thermal-solid coupling simulation, and can accurately obtain the temperature distribution of each position of the friction pair. The present application considers the interaction of various factors such as the fluid flow heat transfer, the heat conduction of the solid, and the frictional heat generation, and avoids the temperature field prediction deviation caused by only considering a single factor. The temperature field simulation involved in the present application can determine the area with too high temperature, so as to optimize the groove shape to improve the heat dissipation performance and keep the temperature of the clutch within a reasonable range during operation.

[0016] The present application also simulates the stress field distribution and can consider the combined action of various stresses such as the thermal stress caused by temperature change and the mechanical stress during the friction process. Through the stress field simulation, these potential problem areas can be found, and the groove shape can be optimized to adjust the stress distribution and improve the fatigue resistance and structural strength of the friction plate.

[0017] The loop of steps S102 and S103 in this application is repeatedly executed, realizing the collaborative work between the thermal-mechanical coupling of the statics simulation module and the fluid-thermal coupling of the fluid simulation module. That is, after the frictional heat calculated by the statics simulation module is transferred to the fluid simulation module as a heat source, the fluid simulation module can accurately simulate the temperature change and flow state of the lubricating oil according to this heat input, and then calculate the heat flux of convective heat transfer, and feedback it to the statics simulation module to update the temperature field and stress field of the solid part. Through such cyclic iteration, the simulation results of each physical field are closer to the actual situation, so as to more accurately evaluate the influence of different groove shapes on the clutch performance under the action of multi-physical field coupling. Combining with the fact that the temperature information can reflect the influence of the groove shape on the heat dissipation efficiency, considering the strength information can reflect the effect of the groove shape on the structural strength and durability of the friction plate, and for the heat transfer information, the influence of the groove shape on the lubricating oil flow and heat exchange can be evaluated. In this way, by comprehensively considering these factors, a groove shape that can achieve a better balance in terms of temperature, strength, heat transfer, etc. can be selected, realizing the optimization of the groove shape of the clutch friction plate and improving the overall performance of the clutch. Brief Description of the Drawings

[0018] In order to more clearly illustrate the technical solutions of the present invention, the drawings required to be used in the description will be briefly introduced below. Obviously, the 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 drawings can also be obtained based on these drawings.

[0019] Figure 1 It is a flowchart of the method for optimizing the groove shape of the clutch friction plate; Figure 2 It is a schematic diagram of the friction plate groove type 1; Figure 3 It is a schematic diagram of the friction plate groove type 2; Figure 4 It is a schematic diagram of the friction plate groove type 3; Figure 5 It is a schematic diagram of an interaction and load boundary; Figure 6 It is a schematic diagram of another interaction and load boundary; Figure 7 It is a schematic diagram of the imported surface mesh state; Figure 8 It is a schematic diagram of the physical continuum model; Figure 9 It is a schematic diagram of the temperature of the counter steel sheet with different groove types; Figure 10 It is a schematic diagram of the temperature of the friction plate substrate with different groove types; Figure 11 It is a schematic diagram of the steel sheet; Figure 12 Schematic diagram of stress values corresponding to different channel steel sheets; Figure 13 Schematic diagram of stress values of different channel friction plates; Figure 14 Schematic diagram of a preferred device for the groove shape of a clutch friction plate; Figure 15 Schematic diagram of an electronic device. Detailed implementation manners

[0020] The method for optimizing the groove shape of the clutch friction plate provided by this application is to solve the problems that during the gear shifting and engagement process of the wet clutch in the transmission, friction occurs and a large amount of heat is generated, resulting in too high an instantaneous temperature rise of the friction pair, too large a surface temperature and stress gradient, and local hot spots, surface ablation, and warping deformation of the friction plate or steel sheet.

[0021] The method for optimizing the groove shape of the clutch friction plate provided by this application evaluates its temperature index and strength index by comparing and analyzing the influence of different friction paper-based groove types on the surface temperature field and stress field of the wet clutch friction pair, and provides a reference for the groove shape design of the friction plate of the wet clutch for commercial vehicle automatic transmissions.

[0022] The following details the specific process of the method for optimizing the groove shape of the clutch friction 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] For the convenience of clearly describing the technical solution of this application, terms such as "first" and "second" are used to distinguish the same items or similar items with basically the same functions and effects. Those skilled in the art can understand that the terms "first" and "second" do not limit the quantity and execution order, and the terms "first" and "second" do not necessarily limit to being different.

[0024] The statements such as "an embodiment" or "some embodiments" described in this application mean that the specific features, structures, or characteristics described in the embodiment are included in one or more embodiments of this application. Thus, the statements such as "in an embodiment", "in some embodiments", "in other some embodiments", "in still other embodiments" and the like that appear in different parts of 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.

[0025] The following will clearly and completely describe the technical solutions in the embodiments of the present invention with reference to 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 of the 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.

[0026] Please refer to Figure 1 The figure shows a flowchart of a preferred method for the groove shape of a clutch friction plate in a specific embodiment. The method includes: S101: Simulate the surface temperature field and stress field distribution of the wet clutch friction pair based on fluid-thermal-solid coupling simulation.

[0027] In some embodiments, a three-dimensional geometric model of the wet clutch friction pair is established. The three-dimensional geometric model of the wet clutch friction pair can reflect the contact relationship and structural characteristics between the friction plate, the counter plate, and the two. The construction method can be completed using currently commonly used CAD software or finite element software, and the dimensions and shapes of each component can be set to be the same as those of the actual wet clutch friction pair.

[0028] In this embodiment, the established wet clutch friction pair is also configured into the static simulation module and the fluid simulation module that support fluid-thermal-solid coupling simulation. In the static simulation module and the fluid simulation module, the material properties of the model are assigned values, including parameters such as the thermal conductivity, specific heat capacity, elastic modulus, and Poisson's ratio of the friction plate and the counter plate.

[0029] This embodiment also sets boundary conditions. For the contact surface of the friction pair, the friction coefficient is also defined, and the value here can be determined comprehensively according to the mating materials of the friction plate and the counter plate and the lubrication conditions under actual working conditions. At the same time, the initial temperature, the assumed ambient temperature at the start of the simulation, and the working condition parameters such as the rotational speed and pressure are set, so as to reflect the operating state of the clutch during actual operation.

[0030] The static simulation module and the fluid simulation module of this embodiment can solve the control equations using corresponding algorithms according to the set model, material properties, and boundary conditions, and simulate the changes in the temperature field and stress field of the friction pair during the working process.

[0031] S102: Use the thermo-mechanical coupling of the static simulation module to simulate frictional heat and transfer the heat to the fluid simulation module.

[0032] Specifically, first, a thermo-mechanical coupling model is constructed in the static simulation module. The elastic modulus, Poisson's ratio, yield strength, etc. of the thermo-mechanical coupling model are given, which are consistent with the corresponding material parameters in step S101 to ensure the accuracy of the mechanical behavior simulation.

[0033] In this embodiment, the pressing force when the clutch is engaged is also set according to the actual working conditions, which is achieved by applying corresponding pressure boundary conditions on the contact surface, and the torque load is converted into a tangential force and applied to the contact area to simulate the interaction between the friction pairs.

[0034] As a way of this embodiment, when calculating the friction heat power density, the thermo-solid coupling model can reflect the heat generated due to friction during the relative sliding process of the friction pairs, providing heat source input for the thermo-mechanical coupling analysis. Considering the friction heat as an internal heat source term in the solid domain, the change of the temperature field is solved.

[0035] S103: Use the fluid-thermal coupling simulation of the fluid simulation module to simulate convective heat transfer and transfer the heat flux to the static simulation module.

[0036] In this embodiment, the fluid domain model in the clutch working cavity can be created using the fluid simulation module, including the flow space of the lubricating oil, accurately describing geometric features such as the cavity shape, inlet and outlet positions, and dimensions.

[0037] Set the fluid material properties. For the lubricating oil, determine parameters such as its density, dynamic viscosity, and specific heat capacity.

[0038] When performing fluid-thermal coupling simulation of convective heat transfer, boundary conditions are also defined. Flow rate, pressure, etc. conditions are set at the fluid inlet and outlet to simulate the actual flow situation of the lubricating oil during the clutch working process. For example, oil with a certain flow velocity flows in at the inlet, and corresponding pressure outlet conditions are set at the outlet. At the same time, at the fluid-solid coupling interface, the solid surface temperature transferred from the static simulation module is applied as a boundary condition to the fluid, enabling the fluid simulation to consider the thermal interaction with the solid.

[0039] In this embodiment, the fluid-thermal coupling solver can be used to solve the fluid flow field and at the same time solve the temperature field, considering the influence of fluid flow on heat transfer, that is, the convective heat transfer process.

[0040] S104: Repeatedly execute steps S102 and S103 to achieve fluid-thermal-solid coupling calculation, and analyze the influence of different groove shapes on the clutch based on the temperature information, strength information, and heat transfer information, and select the groove shape.

[0041] In this embodiment, after the static simulation module first completes the thermo-mechanical coupling to simulate frictional heat and the fluid simulation module completes the fluid-thermal coupling to simulate convective heat transfer, the convective heat flux obtained by the fluid simulation module is fed back to the static simulation module as a boundary condition to update its thermal boundary condition. Iterations are performed repeatedly in this way. Each iteration makes the calculation results of the temperature field, stress field, and flow field in each software closer to the actual working conditions until the difference between the calculation results of two consecutive iterations meets the set convergence criteria, such as the temperature difference being less than a certain threshold and the energy conservation error being within the allowable range. At this time, it is considered that a stable fluid-thermal-solid coupling calculation has been achieved, and the temperature field, stress field distribution, and fluid flow and heat transfer characteristics of the accurate clutch friction pair under the working state are obtained.

[0042] The above-mentioned preferred method for the groove shape of the clutch friction plate analyzes the influence of different groove shapes on the clutch based on temperature information, strength information, and heat transfer information. It can reflect the influence of the groove shape on the heat dissipation efficiency and can also reflect the effect of the groove shape on the structural strength and durability of the friction plate. This embodiment also evaluates the promotion or hindrance effect of the groove shape on the lubricating oil flow and heat exchange based on heat transfer information. By comprehensively considering these factors, a groove shape that can achieve a better balance in multiple aspects such as temperature, strength, and heat transfer can be selected, realizing the optimization of the groove shape of the clutch friction plate and improving the overall performance of the clutch.

[0043] On the basis of the above embodiment, in order to further improve the reliability of the preferred method for the groove shape of the clutch friction plate provided in the above embodiment, as an implementable manner, in one embodiment, the static simulation module performs thermo-solid coupling simulation.

[0044] When performing the simulation, a mesh processing software is used to perform mesh division on the wet clutch. In the mesh division method of the friction substrate of this embodiment, first, the geometry is cleaned to delete the fillets at the teeth, then it is topologically divided using the friction paper substrate, and finally, as Figures 2 to 4 Three groove types are shown for surface mesh and volume mesh generation.

[0045] In some specific embodiments, a thermo-solid coupling model is built based on the static simulation module. The mesh model can be imported into the static simulation module through the mesh processing software. As shown in Tables 1 and 2, the material parameters, interactions, and load boundaries of the thermo-solid coupling model are given.

[0046] Table 1

[0047] Table 2: Interactions and Load Boundaries

[0048] As Figure 5 and Figure 6The contact properties of the statics simulation module are shown. The contact thermal conductivity represents the relationship between the thermal conductivity between two contacting parts and the contact gap or contact pressure. In this paper, the contact thermal conductivity varying with the contact pressure is used. The frictional heat generation page can define the frictional heat generation efficiency and the heat distribution ratio between the contact master and slave surfaces.

[0049] In an embodiment of the present invention, based on step S103, a possible embodiment will be given below to non - restrictively elaborate on its specific implementation scheme.

[0050] S1031: Build a fluid - thermal coupling model based on the fluid simulation module.

[0051] In this embodiment, the spatial dimension used in the simulation is determined based on the modeling work interface of the fluid simulation module. For the simulation of fluid flow and heat transfer in the clutch groove, a two - dimensional axisymmetric model or a three - dimensional model can be selected according to actual needs to meet the calculation accuracy.

[0052] In this embodiment, according to the determined dimension, a geometric model representing the clutch groove watershed is created in the fluid simulation module, specifically including geometric parameters such as the depth, width, spacing, and spiral angle of the groove, and then generated through operations such as stretching and rotating by operating the fluid simulation module to obtain the groove geometric model file.

[0053] S1032: Mesh the wet clutch groove watershed using grid processing software.

[0054] As Figure 7 and Figure 8 shown, the geometric model of the clutch groove watershed created in the previous step is imported into the grid processing software. Select a suitable grid type. For the groove area with regular shape and relatively gentle flow changes, structured grids can be given priority. Optionally, for the areas with groove corners and mutation parts, unstructured grids are used to better fit the geometric shape and ensure the grid quality.

[0055] In this embodiment, the grid size is also controlled. A smaller grid size is set in the area near the friction surface of the groove, where the flow velocity changes greatly and the heat exchange is intense, to capture the detailed changes in the flow field and thermal field. While in the areas far from the key areas and with smaller gradients of the flow field and thermal field, the grid size is appropriately increased to reduce the number of grids on the premise of ensuring the calculation accuracy and improve the calculation efficiency. Through setting the global grid size parameter and combining with the definition of the local encryption area, the grid meshing operation is completed.

[0056] S1033: Model based on the fluid simulation module and import the surface grid.

[0057] In the fluid simulation module, select the clutch groove basin grid file generated and saved by the grid processing software and configure it into the current simulation process. The meshed groove basin grid model is displayed in the graphical interface, and the user needs to carefully check the integrity of the grid to ensure that there are no grid quality problems such as missing elements and overlapping nodes.

[0058] S1034: Model based on the fluid simulation module modeling process and create characteristic curves.

[0059] In this embodiment, according to the physical characteristics of the fluid flow in the clutch groove and the requirements of subsequent simulation settings, on the basis of the imported grid model, use the curve creation tool provided by the software to create characteristic curves. The creation of the curves needs to be combined with the understanding of the clutch working principle and the characteristics of fluid flow to facilitate the use of the software's drawing function to achieve.

[0060] S1035: Use the fluid simulation module to execute the modeling process and convert the Part into a Region.

[0061] In this embodiment, in the fluid simulation module, match the Parts representing the groove basin fluid domain, solid wall surface Part, etc., select the Part to be converted, and convert it into a Region. The purpose is to provide a more unified basis for subsequent operations such as setting physical models and boundary conditions, and classify geometric objects with the same physical properties or simulation processing methods into Regions to make the model structure easy to operate and maintain.

[0062] S1036: Perform mesh division in combination with the fluid simulation module modeling process, and conduct secondary confirmation and optimization.

[0063] In this embodiment, according to the imported grid information, display the grid quality statistical report, including parameter indicators such as the skewness, aspect ratio, and orthogonality quality of the grid. The user can judge whether the grid quality meets the simulation requirements. If it is found that the requirements are not met, the grid optimization tool of the fluid simulation module can be used for local optimization, such as operations such as grid smoothing and re-meshing of specific regions to ensure the reliability and accuracy of the entire groove basin grid in the simulation calculation.

[0064] S1037: Select the physical continuum model, and select a suitable physical continuum model from the physical model library of the fluid simulation module according to the actual properties, flow, and heat transfer state of the fluid in the clutch groove.

[0065] Optionally, by comparing the applicability research literature or experience of different models for similar flow problems, select the most suitable turbulence model. After selection, relevant parameters such as the empirical constants in the turbulence model need to be activated and configured in the corresponding software setting window to ensure the correct operation of the model.

[0066] S1038: Set the physical property parameters based on density, specific heat capacity, thermal conductivity, and dynamic viscosity, and configure them into the energy equation and momentum equation for solution.

[0067] It should be noted that in the material property setting module of the fluid simulation module, find the material item representing the fluid in the groove, and accurately fill in the physical property parameters such as density, specific heat capacity, thermal conductivity, and dynamic viscosity into the corresponding fields according to the technical specification manual of the lubricating oil product or the data obtained through experimental measurement, as shown in Table 3. These physical property parameters are the key quantities describing the thermophysical properties of the fluid, and they will participate in the solution of control equations such as the energy equation and momentum equation, directly determining the accuracy of simulating the flow and heat transfer behavior of the fluid in the groove. After setting, it is necessary to check again to ensure that the parameters are correct.

[0068] Table 3: Physical Property Parameters

[0069] S1039: Set the boundary conditions in the fluid simulation module for different boundaries of the groove basin.

[0070] In this embodiment, the boundary conditions are set in the fluid simulation module for different boundaries of the groove basin.

[0071] For the fluid inlet boundary, set the inlet flow velocity according to the oil supply situation of the lubrication system during the actual operation of the clutch. For the outlet boundary, it can be set as a pressure outlet, and a reference pressure value is given to simulate the situation of the fluid flowing out of the groove basin; for the wall boundary in contact with the solid friction plate and the mating plate, set the wall thermal boundary condition, which can accurately simulate the heat exchange between the fluid and the solid. By reasonably setting the boundary conditions, the simulation model is made to conform to the actual working boundary conditions of the clutch.

[0072] S1040: In the fluid simulation module, establish a rotational motion model and set the rotational speed parameter; if the working rotational speed of the clutch is constant, input a constant rotational speed value; if the rotational speed changes with time or working conditions, write a mathematical expression according to the rotational speed change law to simulate the motion state of the fluid in the groove driven by the rotating components under different working conditions, providing accurate initial flow conditions for subsequent fluid-thermal coupling calculations.

[0073] S1041: Set the rotational motion boundary and the relative rotational speed relationship on the boundary to ensure that the shear force and velocity gradient generated by rotation can be correctly simulated when the fluid crosses this boundary, making the flow field calculation conform to the actual situation. Here, the boundary conditions can be adjusted in combination with the set parameters such as the rotation axis and rotational speed to avoid flow field calculation errors caused by mismatched boundary conditions. After setting, the rationality of the boundary setting can be checked through the preview function.

[0074] S1042: Set the solution step size and convergence criterion.

[0075] In this embodiment, in the solution control settings window of the fluid simulation module, the solution step size parameter is set. The selection of the solution step size can comprehensively consider the change frequency of fluid flow, the time scale of heat conduction, and the requirements for calculation stability.

[0076] In this embodiment, the convergence criteria are set, including the residual convergence criterion and the physical quantity monitoring convergence criterion.

[0077] Exemplarily speaking, for the residual convergence criterion, the residuals of the control equations are calculated in real time during the solution process. When all residuals are less than the set threshold, it is considered that the solution has converged; for the physical quantity monitoring convergence criterion, the user selects to monitor physical quantities such as the flow velocity and temperature at key positions in the groove. When the change of the physical quantity within a continuous number of solution step sizes is less than the set relative error, it is determined that the solution has converged. In this way, it can be ensured that the fluid-thermal coupling simulation calculation can stably and accurately obtain results that conform to the actual situation, providing a reliable basis for the optimization of the groove shape of the clutch friction plate.

[0078] Furthermore, as a refinement and extension of the specific implementation manner of the above embodiment, this embodiment also relates to the co-simulation process of the statics simulation module and the fluid simulation module.

[0079] Specifically, it includes the following methods: S301: Create a new face set in the statics simulation module and store the coupled surfaces.

[0080] In this embodiment, the statics simulation module can be used to identify the surfaces where the groove contacts the friction substrate. The user can determine the coupled surfaces through manual selection or automatic recognition based on geometric features.

[0081] It is also possible to find the surfaces where the groove and the counter steel sheet are coupled. For the surfaces where the groove and the friction paper substrate are coupled, considering the material properties and structural characteristics of the friction paper substrate, they are identified by combining material property screening and geometric position.

[0082] S302: Use the CAE interface of the statics simulation module to output the face set file and add keywords; In the CAE operation interface of the statics simulation module, find the file output or data export function module. Take the previously created coupled surfaces as the output.

[0083] S303: Add a physical model for the fluid domain.

[0084] Here, the physical model settings interface of the fluid simulation module can be opened based on this. According to the actual working conditions of the fluid in the clutch groove and the co-simulation requirements, a physical model for the fluid domain is added.

[0085] For example, the thermophysical properties of the lubricating oil change with temperature. A model for the change of thermophysical properties with temperature is additionally selected and implemented by configuring polynomial coefficients in the fluid simulation module.

[0086] S304: In the fluid simulation module, construct a physical model for the solid components of the clutch.

[0087] In the model construction and management module of the fluid simulation module, create new physical models for the friction base plate, counter steel plate, friction paper base, etc. of the clutch.

[0088] This embodiment can also define material properties for the friction base plate, counter steel plate, and friction paper base of the clutch, and input parameters such as elastic modulus, Poisson's ratio, density, thermal conductivity, and specific heat capacity according to the actual materials used.

[0089] S305: In the fluid simulation module, import the surface set file output by the static simulation module and with keywords, and use the keyword recognition function to quickly locate the three types of coupling surfaces.

[0090] In the fluid simulation module, configure the surface set file output by the static simulation module and with keywords, and use the keyword recognition function of the software to quickly locate the coupling surfaces.

[0091] S306: In the joint simulation setting interface of the fluid simulation module and the static simulation module, determine the coupling variables transmitted between the two.

[0092] In the joint simulation setting interface of the fluid simulation module and the static simulation module, determine the coupling variables that need to be transmitted between the two.

[0093] It should be noted that in the direction from fluid to solid, the coupling variables include the pressure of the fluid on the solid wall, the convective heat transfer flux, etc.

[0094] In the processing method of the pressure variable, the wall pressure data can be transmitted to the static simulation module in real time, an input interface is set at the receiving end of the static simulation module, and the received pressure is applied as an external load to the corresponding solid wall nodes to achieve mechanical coupling.

[0095] The heat flux variable provided in this embodiment can be transmitted to the static simulation module through the convective heat transfer flux calculated by the fluid simulation module, and the static simulation module updates the temperature field calculation of the solid components to ensure the accuracy of thermal coupling.

[0096] S307: In the joint simulation configuration module, set the interface of the static simulation module for the docking interface with the fluid simulation module.

[0097] In the co - simulation configuration, the communication protocol and data transmission method are determined. A protocol that meets the communication requirements of the two modules can be configured to ensure data transmission between the two modules. The static simulation module in this embodiment can receive the coupled variables from the fluid simulation module and accurately convert the received data into computable parameters available to the module according to the predetermined data format and variable definition. For example, the received pressure data is assigned to the corresponding solid wall node load array, and the heat flux data is used to update the parameters related to the thermal boundary conditions, ensuring that the static simulation module can correctly utilize the data transmitted by the fluid simulation to achieve collaborative calculation of the co - simulation.

[0098] Combining the above - mentioned joint simulation of the static simulation module and the fluid simulation module realizes the collaborative work between the thermal - mechanical coupling of the static simulation module and the fluid - thermal coupling of the fluid simulation module. It can consider the mutual influence of physical processes such as frictional heat generation, heat transfer between solids and fluids, and convective heat transfer. The heat flux of convective heat transfer can be calculated and then fed back to the static simulation module to update the temperature field and stress field of the solid part. Through cyclic iteration, the simulation results of each physical field are closer to the actual situation, so as to evaluate the influence of different groove shapes on the clutch performance under the action of multi - physical - field coupling.

[0099] In this embodiment, based on temperature information, strength information, and heat transfer information, the influence of different groove shapes on the clutch is analyzed to select the groove shape. In terms of temperature index, as Figure 9 and Figure 10 shown, the data output from the simulation in this embodiment is sorted to form a visual chart. The temperatures of the mating steel sheet and the friction plate substrate in the wet clutch with different groove - shaped friction plates are compared. For the weak items, the one with a lower temperature is preferably selected.

[0100] Based on Figures 2 to 4 , combined with as Figures 9 to 11 shown, the overall temperature of the mating steel sheet 2 is higher than that of the mating steel sheet 1; for the friction plate temperature, groove type 1 > groove type 2 > groove type 3. To sum up, if the steel sheet is prone to ablation, groove type 3 is preferably selected; if the friction plate is prone to ablation, groove type 3 is preferably selected.

[0101] For the strength index, as Figure 12 and Figure 13 shown, the stresses of the mating steel sheet and the friction plate substrate in the wet clutch with different groove - shaped friction plates are compared, and the one with a smaller stress is preferably selected.

[0102] That is to say, based on Figures 2 to 4 , for the force on the steel sheet, the stress of groove type 1 > groove type 3 > groove type 2. Therefore, if the steel sheet is prone to stress - deformation damage, groove type 2 is selected; for the force on the friction plate, groove type 1 = groove type 2 > groove type 3. If the steel sheet is prone to stress - deformation damage, groove type 3 is selected.

[0103] It should be understood that the sequence numbers of the steps in the above embodiments do not imply the order of execution. The order of execution 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.

[0104] The following are embodiments of the clutch friction plate groove shape optimization device provided by the embodiments of the present disclosure. This device and the clutch friction plate groove shape optimization method of the above embodiments belong to the same inventive concept. For the details not described in detail in the embodiments of the clutch friction plate groove shape optimization device, reference may be made to the embodiments of the above clutch friction plate groove shape optimization method.

[0105] As Figure 14 shown, the device includes: A simulation module that simulates the surface temperature field and stress field distribution of the wet clutch friction pair based on fluid-thermal-solid coupling simulation; A static simulation module for simulating frictional heat and transferring the heat to the fluid simulation module; A fluid simulation module for simulating convective heat transfer and transferring the heat flux to the static simulation module; A cyclic selection module for implementing fluid-thermal-solid coupling calculation, analyzing the influence of different groove shapes on the clutch based on temperature information, strength information, and heat transfer information, and selecting the groove shape.

[0106] As Figure 15 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, it implements the steps of the clutch friction plate groove shape optimization method.

[0107] 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, a personal digital processor, a cellular phone, a smart phone, a wearable device, 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.

[0108] In the embodiments of the present application, the processor 101 may 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 may be implemented in the controller. For a software implementation, an implementation of a process or function may be implemented with a separate software module that allows execution of at least one function or operation. The software code may be implemented by a software application (or program) written in any appropriate programming language. The software code may be stored in the memory and executed by the controller.

[0109] The display module 103 is used to display information input by the user or information provided to the user. The display module 103 may include a display panel, and the display panel may be configured in the form of a liquid crystal display (LCD), an organic light-emitting diode (OLED), or the like.

[0110] The memory 102 may 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.

[0111] The present 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 method for optimizing the groove shape of the clutch friction plate are implemented.

[0112] The storage medium of the present application may adopt any combination of one or more readable media. The readable media may be a readable signal medium or a readable storage medium. The readable storage medium may, for example, but not be 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.

[0113] 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 apparent 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 the embodiments shown herein, but rather to the broadest scope consistent with the principles and novel features disclosed herein.

Claims

1. A clutch friction plate groove shape optimization method, characterized in that: Methods include: S101: Simulate the temperature field and stress field distribution on the friction pair surface of the wet clutch based on the fluid-thermal-solid coupling simulation; S102: simulating friction heat by using the thermal-mechanical coupling of the statics simulation module, and transferring the heat to the fluid simulation module; S103: simulating convective heat transfer using the fluid-heat coupling of the fluid simulation module, and transferring the heat flux to the statics simulation module; S104: Steps S102 and S103 are repeatedly executed in a loop to realize the fluid-heat-solid coupling calculation, and the influence of different groove shapes on the clutch is analyzed based on the temperature information, strength information and heat exchange information, and the groove shape is selected.

2. The clutch friction plate groove shape optimization method according to claim 1, characterized in that: The statics simulation module meshes the wet clutch based on mesh processing software; The friction substrate segmentation method includes: cleaning the geometry to delete the fillets at the teeth, topological segmentation using the friction paper substrate, and finally surface meshing and volume meshing.

3. The clutch friction plate groove shape optimization method according to claim 2, characterized in that: In the method, a thermo-solid coupling model is also built, imported into the statics simulation module, and the material parameters, interactions and load boundaries are configured.

4. The clutch friction plate groove shape optimization method according to claim 3, characterized in that: Material parameters include: density, specific heat capacity, thermal conductivity, thermal expansion coefficient, elastic modulus and Poisson's ratio; The interaction and load boundaries include: the first part and the second part are based on surface binding, contact and rigid connection as the interaction and load boundaries; The interaction and load boundaries also include: the contact surface between the dual steel plate and the outer hub and the retaining ring surface are set in a fully constrained manner, the degree of freedom of the piston center, the piston pressure at the piston center, and the sliding speed of the contact surface between the friction substrate and the inner hub.

5. The clutch friction plate groove shape optimization method according to claim 1 or 2, characterized in that: In the method, a fluid-heat coupling model is also built based on the fluid simulation module; The mesh processing software is used to mesh the groove flow area of ​​the wet clutch; Modeling and importing surface meshes based on the fluid simulation module; Modeling process and creating characteristic curves based on fluid simulation module; Use the fluid simulation module to execute the modeling process and convert the Part into Region; Combine the modeling process of the fluid simulation module to perform mesh generation, and conduct secondary confirmation and optimization; Select a physical continuum model. According to the actual properties, flow and heat transfer state of the fluid in the clutch groove, select a suitable physical continuum model from the physical model library of the fluid simulation module. Set physical property parameters based on density, specific heat capacity, thermal conductivity and dynamic viscosity, and configure them to solve the energy equation and momentum equation; Set boundary conditions in the fluid simulation module for different boundaries of the groove flow domain; In the fluid simulation module, a rotational motion model is established and speed parameters are set; if the clutch operating speed is constant, a constant speed value is input; if the speed changes with time or working conditions, a mathematical expression is written according to the speed change law to simulate the motion state of the fluid in the groove driven by the rotating parts under different working conditions, providing accurate initial flow conditions for subsequent fluid-heat coupling calculations; Set the rotational motion boundary and the relative rotational velocity relationship on the boundary to ensure that the shear force and velocity gradient caused by the rotation can be correctly simulated when the fluid crosses the boundary, so that the flow field calculation conforms to the actual situation; Set the solution step size and convergence criterion.

6. The clutch friction plate groove shape optimization method according to claim 1 or 2, characterized in that: Step S104 also includes: joint simulation of the statics simulation module and the fluid simulation module; Create a new face set in the statics simulation module and store the coupling surface; Use the CAE interface of the statics simulation module to output the face set file and add keywords; Added fluid domain physical model; In the fluid simulation module, a physical model is built for the solid components of the clutch; In the fluid simulation module, import the face set file with keywords output by the statics simulation module, and use the keyword recognition function to quickly locate the three types of coupling surfaces; In the joint simulation setting interface of the fluid simulation module and the statics simulation module, determine the coupling variables transferred between the two; In the joint simulation configuration module, the interface of the statics simulation module is set for the docking interface with the fluid simulation module.

7. The clutch friction plate groove shape optimization method according to claim 6, characterized in that: The steps to determine the coupling variables transferred between the two also include: For the pressure variable, set the output option in the fluid simulation module so that the pressure variable can transmit the wall pressure data to the statics simulation module in real time; The statics simulation module sets a corresponding input interface at the receiving end, applies the received pressure as an external load to the corresponding solid wall node to achieve mechanical coupling; For the heat flux variable, according to the principle of energy conservation, the convective heat transfer heat flux calculated by the fluid simulation module is passed to the statics simulation module, which uses it as part of the thermal boundary conditions to update the temperature field calculation of the solid parts; The statics simulation module outputs the displacement information of the solid surface, which is received by the fluid simulation module and used to update the position of the fluid-solid coupling boundary; The temperature information of the solid is transmitted to the fluid simulation module as the calculation of the fluid thermal properties or thermal boundary conditions. By setting the coupling variables and their transmission mechanism in both directions, the statics and fluid simulation modules are combined.

8. A clutch friction plate groove shape optimization device, characterized in that: The device is used to implement the clutch friction plate groove shape optimization method as described in any one of claims 1 to 7; The device includes: The simulation module simulates the temperature field and stress field distribution on the friction pair surface of the wet clutch based on the fluid-thermal-solid coupling simulation; Statics simulation module, used to simulate friction heat and transfer heat to the fluid simulation module; The fluid simulation module simulates convective heat transfer and transfers the heat flux to the static simulation module; The loop selection module is used to realize the flow-heat-solid coupling calculation, and analyze the influence of different groove shapes on the clutch based on temperature information, strength information and heat exchange information, and select the groove shape.

9. An electronic device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein: When the processor executes the program, the steps of the clutch friction plate groove shape optimization method as described in any one of claims 1 to 7 are implemented.

10. A storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the steps of the clutch friction plate groove shape optimization method as described in any one of claims 1 to 7 are implemented.

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