Scroll plate stress-strain analysis method based on finite element model

Abstract

The invention discloses a scroll plate stress-strain analysis method based on a finite element model, and relates to the technical field of scroll compressors, and the method comprises the following steps: establishing a dynamic and static scroll plate model, and assembling the static scroll plate model and the dynamic scroll plate model; performing pretreatment on the assembled dynamic and static scroll plate model, eliminating fine features, and completing establishment of a fluid domain; performing steady-state thermal calculation on the scroll plate model by using the temperature data as a boundary condition to obtain temperature distribution of the scroll plate model; loading an inertia load by taking the temperature distribution and the pressure data as a temperature load and a pressure load for stress-strain analysis, and outputting a final stress-strain result; the temperature distribution and the pressure data are used as the temperature load and the pressure load for stress-strain analysis, the inertial load is loaded, and the final stress-strain result is output, so that the problem of inaccurate load loading in the prior art is solved, and the precision and the reliability of stress-strain analysis are improved.

Description

Technical Field

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

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

[0003] The existing technology has the problem of inaccurate load loading when performing scroll disk stress-strain analysis. Specifically, in the pressure load calculation, 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 multi-variable process equation. This method ignores the difference in the spatial distribution of pressure on the scroll tooth surface in the same compression chamber. In addition, in the temperature load calculation, linear distribution or block division of the compression chamber and setting a single temperature is usually adopted, which deviates from the actual load distribution and causes the stress-strain analysis results to be inaccurate. Therefore, how to improve the accuracy of load calculation has become a problem that needs to be solved urgently. Summary of the invention

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

[0005] Therefore, the present invention provides a scroll disk stress-strain analysis method based on a finite element model to solve the problem of inaccurate load loading in the scroll disk stress-strain analysis of a scroll compressor.

[0006] In order to solve the above technical problems, the present invention provides the following technical solutions: In a first aspect, the present invention provides a scroll stress and strain analysis method based on a finite element model, which includes establishing a moving scroll model and a 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.

[0007] As a preferred solution of the scroll stress-strain analysis method based on the finite element model of the present invention, the following steps are included in the process of establishing a dynamic and static scroll model and assembling the static scroll model and the dynamic scroll model: 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.

[0008] As a preferred solution of the scroll stress-strain analysis method based on the finite element model of the present invention, the following steps are included in the pre-processing of the assembled dynamic and static scroll models to eliminate small features and complete the establishment of the fluid domain: 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.

[0009] As a preferred solution of the scroll stress-strain analysis method based on the finite element model of the present invention, the following steps are included: meshing the fluid domain, using the dynamic mesh technology, setting boundary conditions according to actual working conditions and defining the movement of the dynamic scroll model, introducing the self-adjusting turbulence model for transient solution, and completing the grid independence test, 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 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.

[0010] As a preferred solution of the scroll stress-strain analysis method based on the finite element model of the present invention, 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.

[0011] As a preferred solution of the scroll stress-strain analysis method based on the finite element model of the present invention, wherein: selecting the moment when the crankshaft angle is equal to the exhaust angle for static structural analysis, and deriving the temperature data and pressure data at this moment includes 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.

[0012] As a preferred solution of the scroll disk stress-strain analysis method based on the finite element model of the present invention, wherein: using temperature data as boundary conditions, performing steady-state thermal calculation on the scroll disk model, and obtaining the temperature distribution of the scroll disk model includes 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.

[0013] As a preferred solution of the scroll stress-strain analysis method based on the finite element model of the present invention, the temperature distribution and pressure data are used as the temperature load and pressure load of the stress-strain analysis, the inertial load is loaded, and the final stress-strain result is output, which 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.

[0014] In a second aspect, the present invention provides a computer device comprising a memory and a processor, wherein the memory stores a computer program, wherein: when the computer program is executed by the processor, any step of the scroll disk stress and strain analysis method based on the finite element model as described in the first aspect of the present invention is implemented.

[0015] In a third aspect, the present invention provides a computer-readable storage medium having a computer program stored thereon, wherein: when the computer program is executed by a processor, any step of the scroll disk stress and strain analysis method based on a finite element model as described in the first aspect of the present invention is implemented.

[0016] The beneficial effects of the present invention are as follows: a dynamic and static scroll model is established, and the static scroll model and the dynamic scroll model are assembled to ensure the geometric accuracy of the model and the accuracy of the relative position relationship; the assembled dynamic and static scroll model is pre-processed to eliminate small features, complete the establishment of the fluid domain, and simplify the model; based on the design parameters of the scroll compressor, 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 data and pressure data at this moment are derived, which solves the problem of ignoring the difference in pressure spatial distribution in the same compression chamber in the traditional method, so that the load data is more in line with the actual situation; 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, and the final stress-strain result is output, which overcomes the problem of inaccurate load loading in the prior art and improves the accuracy and reliability of stress-strain analysis. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other accompanying drawings can be obtained based on these accompanying drawings without paying creative work.

[0018] Figure 1 This is a flow chart of the scroll disk stress-strain analysis method based on the finite element model in Example 1.

[0019] Figure 2 This is a schematic diagram of the transient solution operation in Example 1. DETAILED DESCRIPTION

[0020] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the specific implementation methods of the present invention are described in detail below in conjunction with the accompanying drawings.

[0021] In the following description, many specific details are set forth to facilitate a full understanding of the present invention, but the present invention may also be implemented in other ways different from those described herein, and those skilled in the art may make similar generalizations without violating the connotation of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed below.

[0022] Secondly, the term "one embodiment" or "embodiment" as used herein refers to a specific feature, structure, or characteristic that may be included in at least one implementation of the present invention. The term "in one embodiment" that appears in different places in this specification does not necessarily refer to the same embodiment, nor does it refer to a separate or selective embodiment that is mutually exclusive with other embodiments.

[0023] Example 1, reference Figure 1 and Figure 2 , which is the first embodiment of the present invention, provides a scroll stress and strain analysis method based on a finite element model, comprising the following steps: S1. Establish a moving and stationary scroll model, and assemble the stationary scroll model and the moving scroll model.

[0024] S1.1. 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 matching surfaces, align them, make them completely overlap, and save them.

[0025] 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.

[0026] S1.2. Obtain the design parameters from the design document of the scroll compressor, use the measurement tool in the CAD software to measure the base circle diameters of the movable scroll model and the stationary scroll model in the assembly file, calculate the distance between the center lines of the base circles of the movable scroll model and the stationary scroll model, set it as the rotation radius, and complete the assembly of the movable and stationary scroll models.

[0027] It should be noted that the assembly is performed based on accurate design parameters, which ensures that the relative movement between the scroll plate models is in line with the design intent, thereby improving the working efficiency and stability of the scroll compressor.

[0028] S2. Pre-process the assembled dynamic and static scroll disk model to eliminate small features and complete the establishment of the fluid domain.

[0029] S2.1. Export the assembled moving and stationary scroll disk model from the CAD software into a universal format and transfer it to the pre-processing software; use the Boolean operation tool in the pre-processing software to perform Boolean subtraction operation on the stationary scroll disk model, select the stationary scroll disk model as the base object, and use the moving scroll disk model as the tool body, remove the overlapping part with the moving scroll disk model, and obtain the unoccupied fluid domain inside the stationary scroll disk model.

[0030] It should be noted that, in this process, special attention was paid to retaining the basic features of the static scroll disk model such as the vortex teeth and the bottom structure, while ignoring non-critical features such as chamfers and fillets to simplify the model and improve the efficiency of subsequent analysis.

[0031] S2.2. Create an outer boundary to enclose the entire moving and stationary scroll disk model assembly, perform the same Boolean subtraction operation on the entire moving and stationary scroll disk model assembly, remove the space occupied by the moving and stationary scroll disk model from the outer boundary (including the stationary scroll disk after the Boolean subtraction operation and the original moving scroll disk), and form a complete moving and stationary scroll disk fluid domain model.

[0032] It should be noted that this outer boundary can be a sufficiently large cube or other suitable shape, and its size should be sufficient to contain all possible flow areas involved. Use the geometry creation tool in the pre-processing software to draw the outer boundary according to actual needs. Make sure that this boundary is not too close to the outer edge of the dynamic and static vortex disk model, so as not to affect the real simulation effect of the fluid domain.

[0033] S3. Grid the fluid domain, use dynamic grid technology, set boundary conditions according to actual working conditions and define the movement of the moving vortex disk model, introduce a self-adjusting turbulence model for transient solution, and complete the grid independence test.

[0034] S3.1. According to the geometric shape and complexity of the fluid domain model of the moving and stationary vortex disk, polyhedral mesh is used for division; the global mesh size parameters are set, and the automatic mesh division function in the pre-processing software is used to generate the basic mesh.

[0035] It should be noted that the setting of the global network size parameters is based on the overall size of the fluid domain. For example, a larger mesh size can be set for a larger area, while a finer meshing space is reserved for areas with complex details.

[0036] It should be noted that by rationally selecting the mesh type and optimizing the global mesh size parameters, the computational accuracy can be guaranteed while significantly reducing the computational resource requirements and improving the overall computational efficiency. Polyhedral meshes can better adapt to complex geometric shapes, especially in detailed areas such as the vortex tooth tip, thus ensuring the accuracy of the numerical simulation results.

[0037] S3.2. Based on the generated basic grid, refine the grid density of the vortex tooth tip and exhaust port area, and conduct a comprehensive grid quality check; 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, and set the pressure inlet and pressure outlet boundary conditions at the inlet and outlet of the fluid domain, respectively. The inlet pressure is the suction pressure of the compressor, and the outlet pressure is the exhaust pressure of the compressor. In addition, set the initial temperature of the fluid to the ambient temperature, the initial pressure to the atmospheric pressure, and introduce a self-adjusting turbulence model. Use CFD software (such as ANSYS Fluent) to perform transient solutions to the fluid domain. During the solution process, use the finite volume method to discretely solve the continuity equation, momentum equation, and energy equation; The continuity equation is expressed as: ; in, represents the density of the working fluid, Indicates time, represents the execution of divergence and gradient operations, Indicates speed; The momentum equation is expressed as: ; in, Indicated in The speed of the direction, and represents the index used to identify the velocity component ( , =1, 2, 3 corresponds to , , direction), represents the momentum density, Indicates the speed The direction of the component, and Indicated in Direction and The position of the spatial coordinates in the direction, The volume force is Directional weight; The energy equation can be expressed as: ; in, Indicates temperature, Indicates pressure, represents the thermal conductivity, represents the specific heat capacity, Indicates temperature The energy source term under represents the gradient; After the transient solution is completed, the grid size is reduced and the transient solution is repeated. When the outlet flow 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.

[0038] Furthermore, the transport equations of the turbulent kinetic energy and turbulent dissipation rate of the VLES model are as follows: The expression of the turbulent kinetic energy transport equation is: ; in, represents the turbulent kinetic energy, represents dynamic viscosity, the viscous property of a fluid, represents the turbulent viscosity, the equivalent viscosity caused by turbulent pulsation in turbulent flow, The Prandtl number represents the turbulent kinetic energy and is used to adjust the diffusion characteristics of the turbulent kinetic energy. It is usually set to 1. represents the turbulent kinetic energy generation term, that is, the generation of turbulent kinetic energy due to velocity gradient, It represents the turbulent dissipation rate, that is, the rate at which turbulent kinetic energy is converted into heat energy.

[0039] The expression of the turbulent dissipation rate transport equation is: ; in, The Prandtl number, which represents the turbulent dissipation rate, is used to adjust the diffusion characteristics of the turbulent dissipation rate and is usually set to 1.3. represents the empirical constant used to adjust the generation term of turbulent dissipation rate, usually taken as 1.44, It represents the empirical constant of the dissipation term used to adjust the turbulence dissipation rate, and is usually taken as 1.92.

[0040] The expression of turbulent dissipation rate is: ; in, Indicates that the speed pulsation is The direction component.

[0041] The expression for turbulent viscosity is: ; in, It represents the empirical constant used to adjust the turbulent viscosity, and is usually taken as 0.09.

[0042] The VLES turbulence model adaptively adjusts the ratio of turbulence modeling to turbulence analysis through the resolution control function, which can reduce the influence of the number of grids on the calculation results while ensuring the calculation accuracy. Under this transport equation, the turbulent viscosity in the Reynolds-averaged Navier-Stokes (RANS) model is corrected by introducing the resolution function F, where the value of the resolution function varies between 0 and 1. By controlling the degree of turbulence modeling, it adaptively switches between the Reynolds-averaged Navier-Stokes (RANS) model, the direct numerical simulation model (DNS), and the large eddy simulation (LES). The form of the resolution function is as follows: ; in, Represents the resolution function, which is used to adaptively switch between RANS, DNS and LES models and control the degree of modeling of the turbulence model. It is an empirical constant used to adjust the shape of the resolution function, usually with a value of 0.1. represents the turbulence filter length, i.e., the length scale of the filter in the turbulence model, represents the minimum length scale, that is, the length scale of the smallest eddy in turbulence, It represents the turbulence integrated length scale, that is, the length scale of large eddies in turbulence.

[0043] S4. 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 derive the temperature data and pressure data at this moment.

[0044] S4.1. According to the design parameters of the scroll compressor, the starting angle of the involute is determined, and based on the design of the scroll model, the angle parameter related to the relative position between the orbiting scroll model and the stationary scroll model under specific working conditions is found, and the expression is: ; in, represents the angle parameter, Indicates the starting angle of the involute.

[0045] It should be noted that by accurately calculating the angle parameters, it can be ensured that all calculations in the 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.

[0046] S4.2. Based on the solved angle parameters and the known involute starting angle, calculate the exhaust angle, the expression is: ; in, Indicates the exhaust angle.

[0047] It should be noted that by accurately calculating the exhaust angle, the specific position where the orbiting scroll model and the stationary scroll model begin to separate is clarified, which is crucial to understanding the working principle of the scroll compressor, provides a key time point for subsequent stress-strain analysis, and helps to identify potential design defects and optimize them.

[0048] S4.3. Search for the data set corresponding to the specific crankshaft angle in the time series of the simulation results in the CFD software, determine the relationship between the crankshaft angle and time during the simulation process, filter out the time point that is the same as the target crankshaft angle, and export the pressure and temperature distribution data at the corresponding time point.

[0049] It should be noted that the relationship between the crankshaft angle and time during the simulation is determined by manually calculating the crankshaft angle corresponding to each time step based on the rotation speed set for the simulation (for example, 60 degrees per second), or directly extracting this information from the simulation results. Filter the dataset for the target crankshaft angle: Write a script or use the built-in function of the software to find the time point closest to the target crankshaft angle in the time series, and select the time point with the smallest difference as the target dataset.

[0050] S5. Using the temperature data as boundary conditions, a steady-state thermal calculation is performed on the vortex disk model to obtain the temperature distribution of the vortex disk model.

[0051] S5.1. Import the vortex 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 vortex disk model.

[0052] It should be noted that mapping temperature data is to use the mapping function in the pre-processing software to map the temperature data in the CFD simulation results to the surface nodes of the vortex disk model. 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 position.

[0053] S5.2. Introduce the thermal radiation 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 the temperature distribution; start the steady-state thermal analysis solver to solve the three-dimensional, steady-state, and internal heat source-free heat conduction differential equation to obtain the temperature distribution of the vortex disk model, which is expressed as: ; in, Indicates the thermal conductivity of the material; 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.

[0054] The thermal radiation model is introduced into the FEA software to define the radiation heat transfer conditions between the surface of the scroll disk model and the environment, including: Emissivity setting: The emissivity of the surface of the vortex disk model is set according to the material properties, usually between 0 and 1. For metal surfaces, the emissivity is lower (for example, 0.1 to 0.3), while for non-metal surfaces, the emissivity is higher (for example, 0.8 to 0.9).

[0055] Ambient temperature setting: Set the ambient temperature, which is usually room temperature or other specific working environment temperature.

[0056] S6. Use the temperature distribution and pressure data as the temperature load and pressure load for stress-strain analysis, load the inertial load, and output the final stress-strain results.

[0057] S6.1. The temperature distribution and pressure data obtained by the steady-state thermal calculation are used as the temperature load and pressure load for stress-strain analysis, and are loaded onto the inner and outer surfaces of the scroll teeth of the movable scroll model and the upper end surface of the scroll model.

[0058] It should be noted that in the finite element analysis software, the inner and outer surfaces and the upper end surface of the scroll teeth of the movable scroll model are selected as the pressure loading area; the pressure data is loaded onto the selected surface in the form of a distributed load to ensure that the spatial distribution of the pressure load is consistent with the CFD calculation results.

[0059] S6.2. Set the constraints of the orbiting scroll model according to the actual working state of the scroll compressor.

[0060] Specifically, a fixed constraint is set on the center line of the base circle of the movable scroll model to simulate the supporting role of the compressor bearing, ensuring that the movable scroll model does not undergo unnecessary displacement during the analysis process; a rotational degree of freedom is set on the rotation axis of the movable scroll model to allow the movable scroll model to rotate around the axis, reflecting the motion characteristics of the movable scroll model under actual working conditions and helping to simulate the influence of centrifugal force.

[0061] S6.3. Determine the rotation speed of the scroll disk model according to the design parameters of the scroll disk model to complete the loading of the inertial load.

[0062] It should be noted that the inertial load is applied based on the rotational speed and mass distribution. The centrifugal force on each part of the orbiting scroll model is calculated and loaded into the model as an inertial load.

[0063] S6.4. 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 vortex disk model, and generate a stress-strain distribution diagram of the vortex disk model under given working conditions.

[0064] It should be noted that by reasonably setting the solution parameters, the calculation time can be reduced and the solution efficiency can be improved while ensuring the calculation accuracy; obtaining detailed stress-strain distribution diagrams can help identify potential high-stress areas or areas with large deformations, which not only helps to understand the stress and strain variation laws inside the scroll disk model, but also makes it easier to explain the analysis results to non-professionals, thereby providing strong support for design optimization.

[0065] This embodiment also provides a computer device, which is suitable for the case of a scroll disk stress and strain analysis method based on a 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 computer executable instructions to implement the scroll disk stress and strain analysis method based on a finite element model as proposed in the above embodiment.

[0066] The computer device may be a terminal, and the computer device includes a processor, a memory, a communication interface, a display screen and an input device connected through 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 a computer program. The internal memory provides an environment for the operation of the operating system and the computer program in the non-volatile storage medium. The communication interface of the computer device is used to communicate with an external terminal in a wired or wireless manner, and the wireless manner can be achieved through WIFI, an operator network, NFC (near field communication) or other technologies. The display screen of the computer device may be a liquid crystal display screen or an electronic ink display screen, and the input device of the computer device may be a touch layer covered on the display screen, or a key, trackball or touchpad provided on the housing of the computer device, or an external keyboard, touchpad or mouse, etc.

[0067] The present embodiment also provides a storage medium on which a computer program is stored. When the program is executed by a processor, the method for analyzing the stress and strain of a scroll disk based on a finite element model as proposed in the above embodiment is implemented; the storage medium can be implemented by any type of volatile or non-volatile storage device or a combination thereof, such as a static random access memory (SRAM), an electrically erasable programmable read-only memory (EEPROM), an erasable programmable read-only memory (EPROM), a programmable read-only memory (PROM), a read-only memory (ROM), a magnetic storage device, a flash memory, a magnetic disk or an optical disk.

[0068] In summary, the present invention establishes a dynamic and static scroll model, and assembles the static scroll model and the dynamic scroll model to ensure the geometric accuracy of the model and the accuracy of the relative position relationship; the assembled dynamic and static scroll model is pre-processed to eliminate small features, complete the establishment of the fluid domain, and simplify the model; based on the design parameters of the scroll compressor, 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 data and pressure data at this moment are derived; the problem of ignoring the difference in spatial distribution of pressure in the same compression chamber in the traditional method is solved, so that the load data is more in line with the actual situation; 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, and the final stress-strain result is output, which overcomes the problem of inaccurate load loading in the prior art and improves the accuracy and reliability of stress-strain analysis.

[0069] It should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solutions of the present invention may be modified or replaced by equivalents without departing from the spirit and scope of the technical solutions of the present invention, which should all be included in 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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