A method for stress and strain analysis of a scroll disk based on a finite element model

Abstract

The present invention discloses a method for stress and strain analysis of a scroll disk based on a finite element model, which relates to the technical field of scroll compressors. The method includes: establishing static and dynamic scroll disk models and assembling the static scroll disk model and the dynamic scroll disk model; preprocessing the assembled static and dynamic scroll disk models to eliminate fine features and complete the establishment of the fluid domain; using temperature data as a boundary condition to perform a steady-state thermal calculation on the scroll disk model to obtain the temperature distribution of the scroll disk model; taking the temperature distribution and pressure data as the temperature load and pressure load for stress and strain analysis, applying the inertial load, and outputting the final stress and strain results; taking the temperature distribution and pressure data as the temperature load and pressure load for stress and strain analysis, applying the inertial load, and outputting the final stress and strain results, which overcomes the problem of inaccurate load application in the prior art and improves the accuracy and reliability of stress and strain analysis.

Description

Technical Field

[0001] The present invention relates to the technical field of scroll compressors, and particularly to a method for stress and strain analysis of scroll plates based on a finite element model. Background Art

[0002] With the development of scroll compressor technology, its applications in air conditioners, refrigeration, and heat pump systems are becoming increasingly widespread. Traditional methods for stress and strain analysis of scroll plates mainly rely on simplified models and empirical formulas, which usually assume that pressure and temperature loads are evenly distributed or linearly distributed. However, in actual working conditions, the pressure and temperature distributions inside the scroll plate often have significant spatial differences. In recent years, the application of computational fluid dynamics (CFD) technology has gradually become popular. By simulating the flow field inside the scroll compression chamber, the distribution of pressure and temperature loads can be obtained more accurately. Nevertheless, the existing technology still has limitations in dealing with complex flow states, especially in turbulent flow simulation, where the traditional RANS model is difficult to capture the detailed structure of turbulence.

[0003] When analyzing the stress and strain of scroll plates in the prior art, there is a problem of inaccurate load application. Specifically, in the calculation of pressure loads, the commonly used method is to estimate the pressure of each crescent-shaped compression chamber based on the volume ratio of adjacent compression chambers and the polytropic process equation. This method ignores the spatial distribution differences of pressure on the scroll teeth surface within the same compression chamber. In addition, in the calculation of temperature loads, a linear distribution or a method of dividing the compression chamber into blocks and setting a single temperature is usually adopted, which deviates from the actual load distribution and results in inaccurate stress and strain analysis results. Therefore, how to improve the accuracy of load calculation has become an urgent problem to be solved. Summary of the Invention

[0004] In view of the above existing problems, the present invention is proposed.

[0005] Therefore, the present invention provides a method for stress and strain analysis of scroll plates based on a finite element model to solve the problem of inaccurate load application in the stress and strain analysis of scroll plates of scroll compressors.

[0006] To solve the above technical problems, the present invention provides the following technical solutions:

[0007] In a first aspect, the present invention provides a method for stress and strain analysis of scroll plates based on a finite element model, which includes establishing a static and a dynamic scroll plate model, and assembling the static scroll plate model and the dynamic scroll plate model;

[0008] Performing preprocessing on the assembled static and dynamic scroll plate models to eliminate small features and complete the establishment of the fluid domain;

[0009] Mesh the fluid domain, adopt the dynamic mesh technology, set the boundary conditions according to the actual working conditions and define the motion of the dynamic scroll disk model, introduce a self-adjusting turbulence model for transient solution, and complete the mesh independence test;

[0010] Determine the exhaust angle according to the starting angle of the involute, select the moment when the crankshaft angle is equal to the exhaust angle for static structural analysis, and export the temperature data and pressure data at this moment;

[0011] Use the temperature data as the boundary condition to perform a steady-state heat calculation on the scroll disk model to obtain the temperature distribution of the scroll disk model;

[0012] Take the temperature distribution and pressure data as the temperature load and pressure load for stress-strain analysis, apply the inertial load, and output the final stress-strain results.

[0013] As a preferred scheme of the scroll disk stress-strain analysis method based on the finite element model according to the present invention, wherein: establishing the static and dynamic scroll disk models, and assembling the static scroll disk model and the dynamic scroll disk model includes the following steps,

[0014] Create an assembly file, and use CAD software to import the original design files of the dynamic scroll disk model and the static scroll disk model into the assembly file;

[0015] In the assembly file, select the upper end face of the dynamic scroll disk model and the tooth top face of the static scroll disk model as the mating surfaces for alignment, make the two completely coincide and save;

[0016] Obtain the design parameters from the design documents of the scroll compressor, use the measurement tool in CAD software to measure the base circle diameters of the dynamic scroll disk model and the static scroll disk model in the assembly file, calculate the distance between the center lines of the base circles of the dynamic scroll disk model and the static scroll disk model, set it as the rotation radius, and complete the assembly of the static and dynamic scroll disk models.

[0017] As a preferred scheme of the scroll disk stress-strain analysis method based on the finite element model according to the present invention, wherein: performing preprocessing on the assembled static and dynamic scroll disk models, eliminating small features, and completing the establishment of the fluid domain includes the following steps,

[0018] Export the assembled static and dynamic scroll disk models from CAD software in a common format and transfer them to the preprocessing software;

[0019] Use the Boolean operation tool in the preprocessing software to perform a Boolean subtraction operation on the static scroll disk model, select the static scroll disk model as the base object, use the dynamic scroll disk model as the tool body, remove the overlapping part with the dynamic scroll disk model, and obtain the unoccupied fluid domain inside the static scroll disk model;

[0020] Create an external boundary to enclose the entire dynamic and static scroll disk model assembly, perform the same Boolean subtraction operation on the entire dynamic and static scroll disk model assembly, remove the space occupied by the dynamic and static scroll disk model from the external boundary, and form a complete fluid domain model of the dynamic and static scroll disk.

[0021] As a preferred solution of the scroll disk stress and strain analysis method based on the finite element model according to the present invention, wherein: perform mesh division on the fluid domain, adopt the dynamic mesh technology, set boundary conditions according to the actual working conditions and define the motion of the dynamic scroll disk model, introduce a self-adjusting turbulence model for transient solution, and complete the mesh independence test including the following steps.

[0022] According to the geometric shape and complexity of the fluid domain model of the dynamic and static scroll disk, perform division using polyhedral meshes.

[0023] Set the global mesh size parameter and use the automatic mesh generation function in the preprocessing software to generate the basic mesh.

[0024] Based on the generated basic mesh, refine the mesh density at the tip of the scroll teeth and the exhaust port area, and conduct a comprehensive mesh quality inspection.

[0025] According to the actual working conditions, set the no-slip condition as the boundary condition of the fluid domain, introduce a self-adjusting turbulence model, and use CFD software to perform transient solution on the fluid domain. During the solution process, use the finite volume method to discretely solve the continuity equation, momentum equation, and energy equation.

[0026] After the solution is completed, reduce the mesh size and repeat the transient solution. When the outlet flow rate of the exhaust port enters periodic variation, it indicates that the numerical simulation results converge, and the final temperature field and pressure field data are obtained.

[0027] As a preferred solution of the scroll disk stress and strain analysis method based on the finite element model according to the present invention, wherein: determining the exhaust angle according to the involute starting angle includes the following steps.

[0028] According to the design parameters of the scroll compressor, determine the starting angle of the involute.

[0029] And based on the design of the scroll disk model, find the angular parameters related to the relative position between the dynamic scroll disk model and the static scroll disk model under specific working conditions.

[0030] Based on the solved angular parameters and the known starting angle of the involute, calculate the exhaust angle.

[0031] As a preferred solution of the scroll disk stress and strain analysis method based on the finite element model according to the present invention, wherein: select the moment when the crankshaft angle is equal to the exhaust angle for static structural analysis, and derive the temperature data and pressure data at this moment, including the following steps.

[0032] Find the data set corresponding to this specific crankshaft angle in the time series of the simulation results in the CFD software;

[0033] Determine the relationship between the crankshaft angle and time during the simulation;

[0034] Filter out the time points that are the same as the target crankshaft angle, and export the pressure and temperature distribution data at the corresponding time points.

[0035] As a preferred embodiment of the method for analyzing the stress and strain of the scroll disk based on the finite element model according to the present invention, wherein: using the temperature data as the boundary condition, performing a steady-state heat calculation on the scroll disk model, and obtaining the temperature distribution of the scroll disk model includes the following steps.

[0036] Import the scroll disk model into the finite element analysis software, and map the temperature data from the CFD simulation results to the surface nodes of the scroll disk model through the mapping function in the pre-processing software;

[0037] Set the radiation heat transfer condition between the surface of the scroll disk model and the environment, define the emissivity of the surface of the scroll disk model and the environmental temperature, and consider the influence of radiation heat transfer on the temperature distribution;

[0038] Start the steady-state heat analysis solver, solve the three-dimensional, steady-state, heat conduction differential equation without internal heat sources. During the solving process, simultaneously consider the coupling effect of heat conduction and radiation heat transfer to obtain the temperature distribution of the scroll disk model;

[0039] Verify the steady-state heat calculation results by comparing the temperature data from the CFD simulation with the temperature distribution from the finite element analysis. If there is a deviation, adjust the radiation heat transfer parameters and mesh division, and re-perform the steady-state heat calculation.

[0040] As a preferred embodiment of the method for analyzing the stress and strain of the scroll disk based on the finite element model according to the present invention, wherein: using the temperature distribution and pressure data as the temperature load and pressure load for stress and strain analysis, performing the loading of inertial loads, and outputting the final stress and strain results includes the following steps.

[0041] Use the temperature distribution and pressure data obtained from the steady-state heat calculation as the temperature load and pressure load for stress and strain analysis, and load them onto the inner and outer surfaces of the scroll teeth of the moving scroll disk model and the upper end surface of the scroll disk model;

[0042] Set the constraint conditions of the moving scroll disk model according to the actual working conditions of the scroll compressor;

[0043] Determine the rotational speed of the scroll disk model according to the design parameters of the scroll disk model, and complete the loading of inertial loads;

[0044] Start the stress-strain analysis solver to perform comprehensive stress-strain analysis of fluid-thermal-solid unidirectional coupling, solve the stress distribution and strain distribution of the scroll disk model, and generate the stress-strain distribution diagram of the scroll disk model under given working conditions.

[0045] In a second aspect, the present invention provides a computer device, including a memory and a processor, where the memory stores a computer program, and: when the computer program is executed by the processor, any step of the scroll disk stress-strain analysis method based on a finite element model as described in the first aspect of the present invention is implemented.

[0046] In a third aspect, the present invention provides a computer-readable storage medium, on which a computer program is stored, and: when the computer program is executed by the processor, any step of the scroll disk stress-strain analysis method based on a finite element model as described in the first aspect of the present invention is implemented.

[0047] The beneficial effects of the present invention are as follows: establish static and dynamic scroll disk models, and assemble the static scroll disk model and the dynamic scroll disk model to ensure the geometric accuracy of the model and the accuracy of the relative position relationship; perform preprocessing on the assembled static and dynamic scroll disk models, eliminate small features, complete the establishment of the fluid domain, and simplify the model; based on the design parameters of the scroll compressor, determine the exhaust angle according to the starting angle of the involute, select the moment when the crankshaft rotation angle is equal to the exhaust angle for static structural analysis, and derive the temperature data and pressure data at this moment, solving the problem of ignoring the pressure spatial distribution difference in the same compression chamber in the traditional method, making the load data more in line with the actual situation; use the temperature distribution and pressure data as the temperature load and pressure load for stress-strain analysis, apply the inertial load, and output the final stress-strain results, overcoming the problem of inaccurate load application existing in the prior art, and improving the accuracy and reliability of stress-strain analysis. Description of the Drawings

[0048] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required for description in the embodiments 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, other drawings can be obtained based on these drawings without creative efforts.

[0049] Figure 1 It is a flowchart of the scroll disk stress-strain analysis method based on a finite element model in Embodiment 1.

[0050] Figure 2 It is a schematic diagram of the transient solution operation in Embodiment 1. Detailed Embodiments

[0051] To make the above objects, features, and advantages of the present invention more apparent and understandable, the following detailed description of the specific embodiments of the present invention will be given in conjunction with the accompanying drawings of the specification.

[0052] In the following description, many specific details are set forth in order to provide a thorough understanding of the present invention. However, the present invention may be implemented in other ways different from those described herein. Those skilled in the art may make similar extensions without departing from the connotation of the present invention. Therefore, the present invention is not limited by the specific embodiments disclosed below.

[0053] Secondly, the so-called "one embodiment" or "embodiment" herein refers to a specific feature, structure, or characteristic that may be included in at least one implementation manner of the present invention. The appearances of "in one embodiment" in different places in this specification do not all refer to the same embodiment, nor are they separate or selectively exclusive embodiments from other embodiments.

[0054] Embodiment 1, referring to Figure 1 and Figure 2 , is the first embodiment of the present invention. This embodiment provides a method for analyzing the stress and strain of a scroll disk based on a finite element model, including the following steps:

[0055] S1. Establish a static and dynamic scroll disk model, and assemble the static scroll disk model and the dynamic scroll disk model.

[0056] S1.1. Create an assembly file, and use CAD software to import the original design files of the dynamic scroll disk model and the static scroll disk model into the assembly file; in the assembly file, select the upper end face of the dynamic scroll disk model and the tooth top face of the static scroll disk model as the mating surfaces for alignment, so that the two are completely coincident and saved.

[0057] It should be noted that after importing the original design file into the assembly file, check whether there are any geometric errors or mismatches in the imported model, and make necessary corrections.

[0058] S1.2. Obtain the design parameters from the design documents of the scroll compressor, use the measurement tool in CAD software to measure the base circle diameters of the dynamic scroll disk model and the static scroll disk model in the assembly file, calculate the distance between the base circle center lines of the dynamic scroll disk model and the static scroll disk model, and set it as the rotation radius to complete the assembly of the static and dynamic scroll disk models.

[0059] It should be noted that the assembly based on accurate design parameters ensures that the relative movement between the scroll disk models conforms to the design intention, and improves the working efficiency and stability of the scroll compressor.

[0060] S2. Perform pre-processing on the assembled static and dynamic scroll disk models to eliminate fine features and complete the establishment of the fluid domain.

[0061] S2.1. Export the assembled stationary and moving scroll disk models from the CAD software in a common format and transfer them to the pre-processing software; use the Boolean operation tool in the pre-processing software to perform a Boolean subtraction operation on the stationary scroll disk model. Select the stationary scroll disk model as the base object and the moving scroll disk model as the tool body to remove the overlapping part with the moving scroll disk model, and obtain the unoccupied fluid domain inside the stationary scroll disk model.

[0062] It should be noted that during this process, special attention should be paid to retaining the basic features of the stationary scroll disk model such as scroll teeth and bottom structure, while ignoring non-critical features such as chamfers and fillets to simplify the model and improve the subsequent analysis efficiency.

[0063] S2.2. Create an external boundary to enclose the entire assembled stationary and moving scroll disk model, and perform the same Boolean subtraction operation on the entire assembled stationary and moving scroll disk model. Remove the space occupied by the stationary and moving scroll disk models (including the stationary scroll disk after the Boolean subtraction operation and the original moving scroll disk) from the external boundary to form a complete fluid domain model of the stationary and moving scroll disk.

[0064] It should be noted that this external boundary can be a sufficiently large cube or other suitable shape, and its size should be sufficient to contain all possible flow regions involved. Use the geometry creation tool in the pre-processing software to draw this external boundary according to actual needs. Ensure that this boundary is not too close to the outer edge of the stationary and moving scroll disk model to avoid affecting the true simulation effect of the fluid domain.

[0065] S3. Perform mesh division on the fluid domain, adopt dynamic mesh technology, set boundary conditions according to actual working conditions and define the movement of the moving scroll disk model, introduce a self-adjusting turbulence model for transient solution, and complete the mesh independence test.

[0066] S3.1. According to the geometric shape and complexity of the fluid domain model of the stationary and moving scroll disk, use polyhedral meshes for division; set the global mesh size parameter and use the automatic mesh generation function in the pre-processing software to generate the basic mesh.

[0067] It should be noted that the global network size parameter is set according to the overall size of the fluid domain. For example, a larger mesh size can be set for a larger area, while a more refined mesh division space is reserved for areas with complex details.

[0068] It should be noted that by reasonably selecting the mesh type and optimizing the global mesh size parameter, the computational resource requirements can be significantly reduced while ensuring the calculation accuracy, and the overall computational efficiency can be improved; polyhedral meshes can better adapt to complex geometric shapes, especially at detailed parts such as the tips of scroll teeth, ensuring the accuracy of the numerical simulation results.

[0069] S3.2. Based on the generated basic grid, refine the grid density in the tip region of the scroll teeth and the exhaust port area, and conduct a comprehensive grid quality inspection; according to the actual working conditions, set the no-slip condition as the boundary condition of the fluid domain, that is, the velocity of the fluid at the wall is zero. At the inlet and outlet of the fluid domain, set the pressure inlet and pressure outlet boundary conditions respectively. The inlet pressure is the suction pressure of the compressor, and the outlet pressure is the discharge pressure of the compressor. In addition, set the initial temperature of the fluid to the ambient temperature and the initial pressure to the atmospheric pressure, and introduce a self-adjusting turbulence model. Use CFD software (such as ANSYS Fluent) to perform transient solution for the fluid domain. During the solution process, use the finite volume method to discretely solve the continuity equation, momentum equation, and energy equation;

[0070] The expression of the continuity equation is:

[0071] ;

[0072] where, represents the density of the working fluid, represents time, represents the execution of divergence and gradient operations, represents the velocity;

[0073] The expression of the momentum equation is:

[0074] ;

[0075] where, represents the velocity in the direction, and represent the indices used to identify the velocity components ( , = 1, 2, 3 corresponding to , , directions), represents the momentum density, represents the component of the velocity in the direction, and represent the positions of the spatial coordinates in the direction and direction, represents the component of the body force in the direction;

[0076] The expression of the energy equation is:

[0077] ;

[0078] where, represents the temperature, denotes pressure, denotes thermal conductivity, denotes specific heat capacity, denotes temperature the energy source term at, denotes gradient;

[0079] After the transient solution is completed, reduce the mesh size and repeat the transient solution. When the outlet flow rate at the exhaust port enters periodic variation, it indicates that the numerical simulation results converge, and the final temperature field and pressure field data are obtained.

[0080] Furthermore, the transport equations for the turbulent kinetic energy and the turbulent dissipation rate of the VLES model are as follows:

[0081] The expression of the transport equation for the turbulent kinetic energy is:

[0082] ;

[0083] where, denotes the turbulent kinetic energy, denotes the dynamic viscosity, the viscous property of the fluid, denotes the turbulent viscosity, the equivalent viscosity caused by turbulent pulsations in the turbulence, denotes the Prandtl number of the turbulent kinetic energy, used to adjust the diffusion characteristics of the turbulent kinetic energy, usually taking a value of 1, denotes the generation term of the turbulent kinetic energy, that is, the generation of the turbulent kinetic energy caused by the velocity gradient, denotes the turbulent dissipation rate, that is, the rate at which the turbulent kinetic energy is converted into heat energy.

[0084] The expression of the transport equation for the turbulent dissipation rate is:

[0085] ;

[0086] where, denotes the Prandtl number of the turbulent dissipation rate, used to adjust the diffusion characteristics of the turbulent dissipation rate, usually taking a value of 1.3, denotes the empirical constant used to adjust the generation term of the turbulent dissipation rate, usually taking a value of 1.44, denotes the empirical constant used to adjust the dissipation term of the turbulent dissipation rate, usually taking a value of 1.92.

[0087] The expression of the turbulent dissipation rate is:

[0088] ;

[0089] where, denotes the component of the velocity pulsation in the direction.

[0090] The expression of the turbulent viscosity is:

[0091] ;

[0092] Among them, represents the empirical constant for adjusting the calculation of turbulent viscosity, and its value is usually 0.09.

[0093] The VLES turbulence model adaptively adjusts the ratio of turbulence modeling to turbulence analysis through a resolution control function, and can reduce the influence of the number of grids on the calculation results while ensuring the calculation accuracy. Under this transport equation, by introducing the resolution function F, the turbulent viscosity in the Reynolds-averaged Navier-Stokes (RANS) model is corrected. The value of the resolution function varies between 0 and 1. By controlling the degree of turbulence modeling, it adaptively switches among the Reynolds-averaged Navier-Stokes (RANS) model, direct numerical simulation model (DNS), and large eddy simulation (LES). The form of the resolution function is as follows:

[0094] ;

[0095] Among them, represents the resolution function, which is used to adaptively switch among the RANS, DNS, and LES models and control the degree of turbulence modeling. represents the empirical constant for adjusting the shape of the resolution function, and its value is usually 0.1. represents the turbulent filtering length, that is, the length scale of the filter in the turbulence model. represents the minimum length scale, that is, the length scale of the smallest vortices in the turbulence. represents the turbulent integral length scale, that is, the length scale of the large vortices in the turbulence.

[0096] S4. Determine the exhaust angle according to the involute starting angle, select the moment when the crankshaft angle is equal to the exhaust angle for static structural analysis, and derive the temperature data and pressure data at this moment.

[0097] S4.1. According to the design parameters of the scroll compressor, determine the starting angle of the involute, and based on the design of the scroll disk model, find the angular parameters related to the relative position between the moving scroll disk model and the stationary scroll disk model under specific working conditions. The expression is:

[0098] ;

[0099] Among them, represents the angular parameter. represents the involute starting angle.

[0100] It should be noted that by accurately calculating the angular parameters, it can ensure that all calculations in subsequent steps are based on precise geometric relationships, thereby improving the accuracy of the overall analysis, avoiding errors caused by simplified assumptions, and ensuring the consistency of the involute starting angle with the actual working conditions.

[0101] S4.2. Based on the obtained angular parameters and the known involute starting angle, calculate the exhaust angle, and the expression is:

[0102] ;

[0103] Where, represents the exhaust angle.

[0104] It should be noted that by accurately calculating the exhaust angle, the specific position where the moving scroll model starts to separate from the stationary scroll model is determined, which is crucial for understanding the working principle of the scroll compressor, provides a key time point for subsequent stress and strain analysis, and helps to identify potential design defects and optimize them.

[0105] S4.3. In the time series of the simulation results in the CFD software, find the dataset corresponding to this specific crankshaft rotation angle, determine the relationship between the crankshaft rotation angle and time during the simulation process, filter out the time points with the same target crankshaft rotation angle, and export the pressure and temperature distribution data at the corresponding time points.

[0106] It should be noted that determining the relationship between the crankshaft rotation angle and time during the simulation is based on the set rotational speed in the simulation (for example, rotating 60 degrees per second), manually calculating the corresponding crankshaft rotation angle for each time step, or directly extracting this information from the simulation results. Filter the dataset of the target crankshaft rotation angle: Write a script or use the built-in function of the software to find the time point closest to the target crankshaft rotation angle in the time series, and select the time point with the smallest difference as the target dataset.

[0107] S5. Use the temperature data as the boundary condition to perform a steady-state heat calculation on the scroll model to obtain the temperature distribution of the scroll model.

[0108] S5.1. Import the scroll model into the finite element analysis software, and through the mapping function in the preprocessing software, map the temperature data from the CFD simulation results to the surface nodes of the scroll model.

[0109] It should be noted that mapping the temperature data is to use the mapping function in the preprocessing software to map the temperature data in the CFD simulation results to the surface nodes of the scroll model, and it is necessary to accurately match the position information of each node to ensure that the temperature data can be accurately applied to the corresponding geometric positions.

[0110] S5.2. Introduce the thermal radiation model, set the radiation heat transfer conditions between the surface of the scroll disk model and the environment, define the emissivity of the surface of the scroll disk model and the environmental temperature, and consider the influence of radiation heat transfer on the temperature distribution; start the steady-state thermal analysis solver to solve the three-dimensional, steady-state, and conduction differential equation without internal heat source to obtain the temperature distribution of the scroll disk model, and the expression is:

[0111] ;

[0112] where, represents the thermal conductivity of the material;

[0113] Verify the steady-state heat calculation results by comparing the temperature data from CFD simulation with the temperature distribution from finite element analysis. If there are deviations, adjust the radiation heat transfer parameters and mesh division, and perform the steady-state heat calculation again.

[0114] Introduce the thermal radiation model in the FEA software and define the radiation heat transfer conditions between the surface of the scroll disk model and the environment, specifically including:

[0115] Emissivity setting: Set the emissivity of the surface of the scroll disk model according to the material properties, which is usually between 0 and 1. For metal surfaces, the emissivity is relatively low (e.g., 0.1 to 0.3), while for non-metal surfaces, the emissivity is relatively high (e.g., 0.8 to 0.9).

[0116] Environmental temperature setting: Set the environmental temperature, which is usually the room temperature or the temperature of other specific working environments.

[0117] S6. Take the temperature distribution and pressure data as the temperature load and pressure load for stress-strain analysis, apply the inertial load, and output the final stress-strain results.

[0118] S6.1. Take the temperature distribution and pressure data obtained from the steady-state heat calculation as the temperature load and pressure load for stress-strain analysis, and apply them to the inner and outer surfaces of the scroll teeth of the orbiting scroll disk model and the upper end surface of the scroll disk model.

[0119] It should be noted that in the finite element analysis software, select the inner and outer surfaces of the scroll teeth and the upper end surface of the orbiting scroll disk model as the pressure loading areas; apply the pressure data to the selected surfaces in the form of distributed loads to ensure that the spatial distribution of the pressure load is consistent with the CFD calculation results.

[0120] S6.2. Set the constraint conditions of the orbiting scroll disk model according to the actual working conditions of the scroll compressor.

[0121] Specifically, fixed constraints are set on the center line of the base circle of the moving scroll disk model to simulate the supporting effect of the compressor bearing, ensuring that the moving scroll disk model does not undergo unnecessary displacement during the analysis process; rotational degrees of freedom are set on the rotating shaft of the moving scroll disk model, allowing the moving scroll disk model to rotate around the axis, reflecting the motion characteristics of the moving scroll disk model under actual working conditions and helping to simulate the influence of centrifugal force.

[0122] S6.3. Determine the rotational speed of the scroll disk model according to the design parameters of the scroll disk model, and complete the loading of the inertial load.

[0123] It should be noted that the loading of the inertial load is based on the rotational speed and mass distribution, calculates the centrifugal force received by each part of the moving scroll disk model, and takes it as the inertial load to be loaded into the model.

[0124] S6.4. Start the stress-strain analysis solver, perform a comprehensive stress-strain analysis of fluid-thermal-solid unidirectional coupling, solve the stress distribution and strain distribution of the scroll disk model, and generate the stress-strain distribution diagram of the scroll disk model under the given working conditions.

[0125] It should be explained that by reasonably setting the solution parameters, the calculation time can be reduced while ensuring the calculation accuracy, improving the solution efficiency; obtaining a detailed stress-strain distribution diagram helps to identify potential high-stress areas or areas with large deformations, which not only helps to understand the stress and strain change laws inside the scroll disk model, but also facilitates explaining the analysis results to non-professionals, thus providing strong support for design optimization.

[0126] This embodiment also provides a computer device, which is applicable to the case of the scroll disk stress-strain analysis method based on the finite element model, including: a memory and a processor; the memory is used to store computer-executable instructions, and the processor is used to execute the computer-executable instructions to implement the scroll disk stress-strain analysis method based on the finite element model proposed in the above embodiment.

[0127] The computer device may be a terminal, which includes a processor, a memory, a communication interface, a display screen, and an input device connected via a system bus. Among them, the processor of the computer device is used to provide computing and control capabilities. The memory of the computer device includes a non-volatile storage medium and an internal memory. The non-volatile storage medium stores an operating system and computer programs. The internal memory provides an environment for the operation of the operating system and computer programs in the non-volatile storage medium. The communication interface of the computer device is used to communicate with external terminals in a wired or wireless manner, and the wireless manner can be achieved through WIFI, carrier networks, NFC (Near Field Communication), or other technologies. The display screen of the computer device can be a liquid crystal display screen or an electronic ink display screen. The input device of the computer device can be a touch layer covering the display screen, or buttons, trackballs, or touchpads provided on the housing of the computer device, or an external keyboard, touchpad, or mouse, etc.

[0128] This embodiment also provides a storage medium, on which a computer program is stored. When the program is executed by a processor, it implements the method for analyzing the stress and strain of a scroll disk based on a finite element model as proposed in the above embodiment; the storage medium can be implemented by any type of volatile or non-volatile storage device or a combination thereof, such as static random access memory (Static Random Access Memory, abbreviated as SRAM), electrically erasable programmable read-only memory (Electrically Erasable Programmable Read-Only Memory, abbreviated as EEPROM), erasable programmable read-only memory (Erasable Programmable Read Only Memory, abbreviated as EPROM), programmable read-only memory (Programmable Red-Only Memory, abbreviated as PROM), read-only memory (Read-Only Memory, abbreviated as ROM), magnetic memory, flash memory, magnetic disks, or optical discs.

[0129] In summary, the present invention establishes a static and dynamic scroll disk model, assembles the static scroll disk model and the dynamic scroll disk model to ensure the geometric accuracy of the model and the accuracy of the relative position relationship; pre-processes the assembled static and dynamic scroll disk model to eliminate small features, completes the establishment of the fluid domain, and simplifies the model; based on the design parameters of the scroll compressor, determines the exhaust angle according to the starting angle of the involute, selects the moment when the crankshaft rotation angle is equal to the exhaust angle for static structural analysis, and derives the temperature data and pressure data at this moment; solves the problem of ignoring the pressure space distribution difference in the same compression chamber in the traditional method, making the load data more in line with the actual situation; uses the temperature distribution and pressure data as the temperature load and pressure load for stress and strain analysis, applies the inertial load, and outputs the final stress and strain results, overcoming the problem of inaccurate load application in the prior art, and improving the accuracy and reliability of stress and strain analysis.

[0130] It should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit them. Although the present invention has been described in detail with reference to the preferred embodiments, those of ordinary skill in the art should understand that the technical solutions of the present invention can be modified or equivalently replaced without departing from the spirit and scope of the technical solutions of the present invention, and they should all be covered by the scope of the claims of the present invention.

Claims

1. A scroll stress and strain analysis method based on a finite element model, characterized in that: include, Establishing a moving and stationary scroll model, and assembling the stationary scroll model and the moving scroll model; The assembled dynamic and static scroll disk model is pre-processed to eliminate small features and complete the establishment of the fluid domain; The fluid domain is meshed, and the dynamic mesh technology is used to set boundary conditions and define the motion of the moving scroll model according to the actual working conditions. The self-adjusting turbulence model is introduced for transient solution, and the mesh independence test is completed. The exhaust angle is determined according to the starting angle of the involute, and the moment when the crankshaft angle is equal to the exhaust angle is selected for static structural analysis, and the temperature and pressure data at this moment are derived; Using temperature data as boundary conditions, steady-state thermal calculations are performed on the vortex disk model to obtain the temperature distribution of the vortex disk model. The temperature distribution and pressure data are used as the temperature load and pressure load for stress-strain analysis, and the inertial load is loaded to output the final stress-strain results.

2. The scroll stress-strain analysis method based on the finite element model according to claim 1, characterized in that: Establishing a moving and stationary scroll model and assembling the stationary scroll model and the moving scroll model includes the following steps: Create an assembly file, and use CAD software to import the original design files of the orbiting scroll model and the stationary scroll model into the assembly file; In the assembly file, select the upper end surface of the orbiting scroll model and the tooth top surface of the stationary scroll model as the mating surfaces, align them, make them completely overlap, and save them; The design parameters are obtained from the design documents of the scroll compressor. The base circle diameters of the orbiting scroll model and the stationary scroll model in the assembly file are measured using the measurement tools in the CAD software. The distance between the base circle center lines of the orbiting scroll model and the stationary scroll model is calculated and set as the rotation radius to complete the assembly of the orbiting and stationary scroll models.

3. The scroll stress-strain analysis method based on the finite element model according to claim 2, characterized in that: The assembled dynamic and static scroll model is pre-processed to eliminate small features and complete the establishment of the fluid domain, including the following steps: Export the assembled dynamic and static scroll models from the CAD software into a universal format and transfer them to the pre-processing software; The Boolean operation tool in the pre-processing software is used to perform a Boolean subtraction operation on the static scroll model. The static scroll model is selected as the base object, the orbiting scroll model is used as the tool body, and the overlapping part with the orbiting scroll model is removed to obtain the unoccupied fluid domain inside the static scroll model. An external boundary is created to surround the entire moving and stationary scroll disk model assembly, and the same Boolean subtraction operation is performed on the entire moving and stationary scroll disk model assembly to remove the space occupied by the moving and stationary scroll disk model from the external boundary to form a complete moving and stationary scroll disk fluid domain model.

4. The scroll stress-strain analysis method based on the finite element model according to claim 3, characterized in that: The fluid domain is meshed, dynamic mesh technology is used, boundary conditions are set according to actual working conditions, the motion of the moving vortex disk model is defined, a self-adjusting turbulence model is introduced for transient solution, and the mesh independence test is completed. The following steps are included: According to the geometric shape and complexity of the fluid domain model of the moving and stationary scroll disk, polyhedral meshes are used for division; Set the global mesh size parameters and use the automatic meshing function in the pre-processing software to generate the basic mesh; Based on the generated base mesh, refine the mesh density of the swirl tip and exhaust port area, and perform a comprehensive mesh quality check; According to the actual working conditions, the no-slip condition is set as the boundary condition of the fluid domain, and the self-adjusting turbulence model is introduced. The CFD software is used to perform transient solution of the fluid domain. During the solution process, the finite volume method is used to discretely solve the continuity equation, momentum equation and energy equation. After the solution is completed, the grid size is reduced and the transient solution is repeated. When the outlet flow rate of the exhaust port enters a periodic change, it means that the numerical simulation results converge, and the final temperature field and pressure field data are obtained.

5. The scroll stress-strain analysis method based on the finite element model according to claim 4, characterized in that: Determining the exhaust angle according to the involute starting angle includes the following steps: Determine the starting angle of the involute according to the design parameters of the scroll compressor; Based on the design of the scroll disk model, the angle parameters related to the relative position between the orbiting scroll disk model and the stationary scroll disk model under specific working conditions are found; Based on the solved angle parameters and the known involute starting angle, the exhaust angle is calculated.

6. The scroll stress-strain analysis method based on the finite element model according to claim 5, characterized in that: The moment when the crankshaft angle is equal to the exhaust angle is selected for static structural analysis. The temperature and pressure data at this moment are derived in the following steps: Find the data set corresponding to the specific crankshaft angle in the time series of simulation results in the CFD software; Determine the relationship between crankshaft angle and time during the simulation; The time points that are the same as the target crankshaft angle are selected, and the pressure and temperature distribution data at the corresponding time points are exported.

7. The scroll stress-strain analysis method based on the finite element model according to claim 6, characterized in that: Using temperature data as boundary conditions, steady-state thermal calculation is performed on the vortex disk model to obtain the temperature distribution of the vortex disk model, including the following steps: Import the scroll disk model into the finite element analysis software, and use the mapping function in the pre-processing software to map the temperature data from the CFD simulation results to the surface nodes of the scroll disk model; Set the radiation heat transfer conditions between the surface of the vortex disk model and the environment, define the emissivity of the surface of the vortex disk model and the ambient temperature, and consider the influence of radiation heat transfer on temperature distribution; Start the steady-state thermal analysis solver to solve the three-dimensional, steady-state, heat conduction differential equation without internal heat source. During the solution process, the coupling effect of heat conduction and radiation heat transfer is considered at the same time to obtain the temperature distribution of the vortex disk model. The steady-state thermal calculation results are verified by comparing the temperature data of CFD simulation with the temperature distribution of finite element analysis. If there is a deviation, the radiation heat transfer parameters and mesh division are adjusted and the steady-state thermal calculation is performed again.

8. The scroll stress-strain analysis method based on the finite element model according to claim 7, characterized in that: The temperature distribution and pressure data are used as the temperature load and pressure load for stress-strain analysis, and the inertial load is loaded. The output of the final stress-strain results includes the following steps: The temperature distribution and pressure data obtained by the steady-state thermal calculation are used as the temperature load and pressure load for the stress-strain analysis, and are loaded onto the inner and outer surfaces of the scroll teeth of the orbiting scroll model and the upper end surface of the scroll model; According to the actual working state of the scroll compressor, the constraint conditions of the orbiting scroll model are set; The rotation speed of the scroll disk model is determined according to the design parameters of the scroll disk model to complete the loading of the inertial load; Start the stress-strain analysis solver to perform a comprehensive stress-strain analysis of fluid-heat-solid one-way coupling, solve the stress distribution and strain distribution of the scroll disk model, and generate a stress-strain distribution diagram of the scroll disk model under given working conditions.

9. A computer device comprising a memory and a processor, wherein the memory stores a computer program, wherein: When the processor executes the computer program, the steps of the scroll stress and strain analysis method based on the finite element model described in any one of claims 1 to 8 are implemented.

10. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the steps of the scroll stress and strain analysis method based on a finite element model described in any one of claims 1 to 8 are implemented.

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