A method and system for multi-field coupling reliability simulation analysis of a screw compressor

Abstract

A kind of screw compressor multi-field coupling reliability simulation analysis method and system, simulation analysis method includes establishing the solid domain model and fluid domain model of screw compressor;The computational fluid dynamics physical field is configured to the fluid domain model of screw compressor, and the conjugate heat transfer physical field and solid mechanics physical field are configured to the solid domain model of screw compressor;Establish heat-flow-solid coupling analysis model, simulate the multi-field coupling scene of screw compressor, and solve the computational fluid dynamics physical field, the temperature data of the computational fluid dynamics physical field is transmitted to the conjugate heat transfer physical field, while the pressure fluctuation data of the computational fluid dynamics physical field and the temperature data of the conjugate heat transfer physical field are cooperatively transmitted to the solid mechanics physical field;Obtain the solution result of heat-flow-solid coupling analysis model, judge whether the structural strength and deformation of screw compressor meet the requirements.This application can realize the accurate check to the structural strength and key clearance in the operation process of screw compressor.

Description

Technical Field

[0001] This invention relates to the field of screw compressor simulation analysis technology, specifically to a multi-field coupling reliability simulation analysis method and system for screw compressors. Background Technology

[0002] Screw compressors, as core equipment in positive displacement fluid machinery, are widely used in key fields such as petrochemicals, mining and metallurgy, energy and power, and rail transportation due to their advantages of compact structure, stable operation, high efficiency and energy saving, and wide adaptability to various working conditions. Their operational reliability directly determines the continuous operation capability of the entire industrial system, and structural strength and the clearance between moving and stationary components are the core indicators affecting reliability. As a typical rotating machine, screw compressors have inherent non-uniform clearances between the male and female rotors and the casing, and between the rotors themselves. During operation, fluid leakage is inevitable. This leakage characteristic further enhances the non-uniformity and unsteadiness of the internal temperature and pressure fields, forming a complex transient fluid-thermal environment. The transient pressure pulsations and temperature distribution in the fluid domain directly induce stress changes and deformations in the solid structure. If the deformation exceeds the critical clearance threshold, it can easily lead to contact wear between the male and female rotors and the casing, or even jamming, resulting in equipment downtime and economic losses.

[0003] Existing screw compressor reliability simulation analysis techniques have several shortcomings: First, most analysis methods are limited to single-physics field simulation, such as conducting only pure structural strength analysis or pure flow field characteristic analysis, ignoring the coupling effect between fluid, heat, and solid components, and failing to accurately reflect the dynamic response of the equipment under actual operating conditions; Second, some coupled simulation methods do not consider the heat capacity characteristics of the solid domain itself, directly using the fluid working medium temperature to replace the rotor surface temperature, resulting in large deviations in temperature distribution calculations, which in turn affect the accuracy of structural deformation and strength verification; Third, in the coupled analysis process, there is insufficient consideration for the time-domain coordinated transmission of transient pressure pulsation loads in the fluid domain and external dynamic loads, and no dedicated verification module is set up for the gaps between the core dynamic and static components of the screw compressor, making it difficult to accurately determine the actual operability of the equipment. Summary of the Invention

[0004] The purpose of this invention is to address the problems in the prior art by providing a multi-field coupling reliability simulation analysis method and system for screw compressors. This method considers the thermal-fluid-solid multi-field coupling effect of screw compressors, enabling accurate verification of structural strength and critical clearances during screw compressor operation, and reducing the deviation between simulation results and actual operating conditions.

[0005] To achieve the above objectives, the present invention provides the following technical solution: Firstly, a multi-field coupling reliability simulation analysis method for screw compressors is provided, including: Establish solid domain and fluid domain models for screw compressors; Computational fluid dynamics physics fields are configured for the fluid domain model of the screw compressor, and conjugate heat transfer physics fields and solid mechanical physics fields are configured for the solid domain model of the screw compressor. A thermo-fluid-solid coupled analysis model is established based on the computational fluid dynamics (CFD) physical field, the conjugate heat transfer physical field, and the solid mechanics physical field. The multi-field coupled scenario of the screw compressor is simulated using the thermo-fluid-solid coupled analysis model, and the CFD physical field is solved. The temperature data of the CFD physical field is transferred to the conjugate heat transfer physical field, and the pressure pulsation data of the CFD physical field and the temperature data of the conjugate heat transfer physical field are transferred to the solid mechanics physical field in a coordinated manner. Obtain the solution results of the thermo-fluid-structure interaction analysis model to determine whether the structural strength and deformation of the screw compressor meet the requirements.

[0006] As a preferred embodiment, in the step of establishing the solid domain model and fluid domain model of the screw compressor, the solid domain model of the screw compressor includes models related to the male and female rotors, the casing, and the bearing housing. The male and female rotors are a pair of meshing helical rotors that can complete the compression and transportation of the working fluid through rotation. The suction and exhaust end face gaps, tooth tip gaps, and tooth inter-tooth gaps are reserved between the male and female rotors and the casing to compensate for the machining errors of the parts and the force and heat deformation during operation.

[0007] As a preferred embodiment, in the step of establishing the solid domain model and fluid domain model of the screw compressor, the fluid domain model of the screw compressor includes a dynamic fluid domain model and a static fluid domain model; the dynamic fluid domain model is generated based on the rotor profile and related structural parameters, and the static fluid domain model is obtained by performing Boolean operations on the solid domain model, ensuring the spatial positional coordination between the fluid domain and the solid domain.

[0008] As a preferred approach, in the step of establishing the solid domain model and fluid domain model of the screw compressor, the dynamic fluid domain and the static fluid domain are meshed, and the mesh near the coupling interface is refined to improve the calculation accuracy of the load transfer process.

[0009] As a preferred embodiment, the step of configuring the computational fluid dynamics physics field for the fluid domain model of the screw compressor includes: Define the inlet, outlet, and wall boundary conditions of the fluid domain, and define the interface between the fluid domain and the solid domain as the thermal-fluid-solid coupling interface to realize the effective transfer of fluid load to the solid domain; Based on the actual physical duration of the current operating conditions, set the corresponding simulation step size and simulation duration of the simulation process to ensure the realistic simulation of the fluid dynamic characteristics in the time domain; Based on the operating medium and operating parameters of the screw compressor, configure the relevant parameters of the computational fluid dynamics physical field.

[0010] As a preferred approach, the steps for configuring conjugate heat transfer physics fields for the solid domain model of a screw compressor include: The material properties of the solid domain model are defined to provide basic parameters for heat transfer calculations and structural mechanics analysis; the material properties of the solid domain model include density, elastic modulus, Poisson's ratio, thermal diffusivity, and coefficient of thermal expansion. The solid domain model is meshed to generate a solid domain mesh. The interface in the solid domain model that contacts the fluid domain is defined as the thermal-fluid-solid coupling interface, which is used to receive fluid loads. By embedding a solid domain grid into the fluid domain grid of the computational fluid dynamics physical field, conjugate heat transfer calculations are performed. The interface between the solid domain grid and the fluid domain grid is defined as the thermal-fluid-solid coupling interface, thereby realizing the synchronous calculation of the heat transfer process in the fluid domain and the solid domain and obtaining the temperature distribution of the solid structure. Configure the parameters of the conjugate heat transfer physical field according to the heat transfer analysis requirements.

[0011] As a preferred approach, the steps for configuring solid mechanical physics fields in the solid domain model of a screw compressor include: A fixed constraint is applied to the bottom of the solid domain model to simulate the actual installation state of the equipment; the bolt connection surfaces between the components of the solid domain are set to frictional contact, and the tightening effect of the bolts is simulated by beam elements and preload to ensure the realistic reproduction of the structural connection relationship; A gravity load is applied vertically to the solid domain model; an external dynamic load time history is applied, which is obtained by performing an inverse Fourier transform on the response spectrum of the external dynamic load, and the time step and total duration of the external dynamic load in the time domain are consistent with the physical field of the computational fluid dynamics, so as to realize the simulation of the synergistic effect of the load in the time domain; the interface in the solid domain model that contacts the fluid domain is defined as the thermo-fluid-solid coupling interface, which is used to receive the transient force pulsating load of fluid pressure; Configure the relevant parameters of the solid mechanics physical field according to the properties of solid materials and the requirements of mechanical analysis.

[0012] As a preferred embodiment, the steps of obtaining the solution results of the thermo-fluid-structure interaction analysis model and determining whether the structural strength and deformation of the screw compressor meet the requirements include: simulating the dynamic response of the screw compressor under the combined action of internal fluid pressure load, thermal load, and external dynamic load during operation; extracting the maximum equivalent stress of the structure from the calculation results, comparing the maximum equivalent stress with the allowable stress of the material, and determining that the structural strength of the screw compressor meets the requirements if the maximum equivalent stress is less than the allowable stress of the material; otherwise, it does not; extracting the deformation of each part of the structure from the calculation results and performing clearance checks, and determining that the deformation of the screw compressor meets the operating requirements if all relevant deformations are less than the corresponding set safety clearance threshold; otherwise, it does not.

[0013] As a preferred embodiment, in the step of extracting the deformation of each part of the structure from the calculation results and performing gap verification, the objects of verification include the axial relative deformation of the male and female rotors and the intake end face of the housing, the axial relative deformation of the male and female rotors and the exhaust end face of the housing, the radial relative deformation of the male and female rotor tooth tips and the rotor cavity, and the normal relative deformation between the male and female rotor teeth.

[0014] Secondly, a multi-field coupling reliability simulation analysis system for screw compressors is provided, including: The solid domain and fluid domain model building module is used to build the solid domain and fluid domain models of the screw compressor. The physics configuration module is used to configure computational fluid dynamics physics fields for the fluid domain model of the screw compressor, and to configure conjugate heat transfer physics fields and solid mechanical physics fields for the solid domain model of the screw compressor. The thermal-fluid-structure interaction (TFI) module is used to establish a TFI model based on computational fluid dynamics (CFD), conjugate heat transfer, and solid mechanics. It is used to simulate multi-field coupling scenarios of screw compressors and solve the CFD model. The temperature data from the CFD model is transferred to the conjugate heat transfer model, and the pressure pulsation data from the CFD model and the temperature data from the conjugate heat transfer model are transferred to the solid mechanics model. The reliability solution and judgment module is used to obtain the solution results of the thermal-fluid-structure interaction analysis model and determine whether the structural strength and deformation of the screw compressor meet the requirements.

[0015] Compared with the prior art, the present invention has at least the following beneficial effects: This invention embeds a solid-domain mesh of a screw compressor into a fluid-domain mesh for conjugate heat transfer calculations. This allows for accurate acquisition of the temperature distribution on the rotor surface and other solid structures. Compared to existing technologies that do not introduce a solid domain, ignore the rotor's own heat capacity, or use the working fluid temperature on the rotor surface to replace the rotor surface temperature, this invention effectively reduces temperature calculation bias, thereby significantly improving the accuracy of structural deformation and reliability calculations under thermo-fluid-structure interaction. By establishing a thermo-fluid-structure interaction analysis model, this invention integrates the significant non-uniformity and unsteady transient pressure pulsations and temperature distribution caused by the screw compressor's non-uniform clearance and leakage characteristics, along with the time history of external dynamic loads, into the structural reliability analysis. This achieves transient unidirectional thermo-fluid-structure interaction analysis. Compared to existing technologies that perform static structural analysis under static conditions, this method more realistically simulates the structural dynamic response of the screw compressor under actual operating conditions, making the reliability analysis results more closely reflect the actual operating state of the equipment. This invention utilizes a thermo-fluid-structure interaction (TFI) model to simulate multi-field coupled scenarios of a screw compressor. It clarifies the solution sequence and data transfer path for each physical field. When solving the computational fluid dynamics (CFD) physical field, the screw compressor, as a typical rotating machine, exhibits inherent non-uniform gaps between its internal rotors and casing, and between the rotors. Fluid leakage is inevitable during operation, exacerbating the non-uniformity and unsteadiness of the internal temperature and pressure fields, creating a complex transient hydrothermal environment. Therefore, the established TFI model accurately solves the flow field, providing accurate transient fluid pressure fluctuations and temperature distributions for subsequent solutions. The temperature data from the CFD physical field is then transferred to the conjugate heat transfer physical field. Simultaneously, the pressure fluctuation data from the CFD physical field and the temperature data from the conjugate heat transfer physical field are collaboratively transferred to the solid mechanics physical field. This provides accurate load input for structural dynamic response analysis, ensuring the accuracy and reliability of the multi-field coupled simulation, reducing the deviation between simulation results and actual operating conditions, and effectively improving the accuracy of reliability assessment.

[0016] Furthermore, this invention, targeting the structural characteristics of screw compressors, constructs a relative deformation verification module based on four sets of key gaps. Building upon conventional structural strength verification, it focuses on the accuracy of key gaps between moving and stationary components. The verification objects include the axial relative deformation between the male and female rotors and the suction end face of the housing, the axial relative deformation between the male and female rotors and the exhaust end face of the housing, the radial relative deformation between the rotor tooth tips and the rotor cavity, and the normal relative deformation between the male and female rotor teeth. Compared to existing technologies that are limited to single physical field or overall performance verification, this invention's method can accurately determine whether the relative deformation of moving and stationary components exceeds a safety threshold under multi-field coupling conditions, effectively preventing faults such as contact, wear, or even jamming of moving and stationary components during operation, thus ensuring the operability and operational stability of the screw compressor. Attached Figure Description

[0017] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of the present invention. For those skilled in the art, other related drawings can be obtained from these drawings without creative effort.

[0018] Figure 1 Flowchart of the multi-field coupling reliability simulation analysis method for screw compressors according to an embodiment of the present invention; Figure 2 A three-dimensional structural schematic diagram of a screw compressor according to an embodiment of the present invention; In the attached diagram: 21-Intake port; 22-Male rotor; 23-Main body; 24-Ball bearing; 25-Female rotor; 26-Cylindrical roller bearing. Detailed Implementation

[0019] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, those skilled in the art can obtain other embodiments without creative effort.

[0020] To address the shortcomings of existing screw compressor reliability simulation and analysis techniques, such as neglecting multi-field coupling effects, low accuracy in temperature calculations, and lack of critical clearance verification, this invention proposes a multi-field coupling reliability simulation and analysis method for screw compressors. Please refer to [link / reference]. Figure 1 The method of this invention mainly includes the following steps: S1. Establish the solid domain model and fluid domain model of the screw compressor; S2. Configure computational fluid dynamics physics fields for the fluid domain model of the screw compressor, and configure conjugate heat transfer physics fields and solid mechanical physics fields for the solid domain model of the screw compressor. S3. Based on the computational fluid dynamics physical field, the conjugate heat transfer physical field, and the solid mechanics physical field, a thermo-fluid-solid coupling analysis model is established. The thermo-fluid-solid coupling analysis model is used to simulate the multi-field coupling scenario of the screw compressor, and the computational fluid dynamics physical field is solved. The temperature data of the computational fluid dynamics physical field is transferred to the conjugate heat transfer physical field. At the same time, the pressure pulsation data of the computational fluid dynamics physical field and the temperature data of the conjugate heat transfer physical field are transferred to the solid mechanics physical field in a coordinated manner. S4. Obtain the solution results of the thermal-fluid-structure interaction analysis model and determine whether the structural strength and deformation of the screw compressor meet the requirements.

[0021] In one possible implementation, the solid domain model constructed in step S1 should at least include the male and female rotors, housing and bearing housing of the screw compressor, wherein the male and female rotors are a pair of meshing helical rotors that can complete the compression and transportation of the working fluid by rotation. The suction and exhaust end face gap, tooth tip gap and tooth gap must be reserved between the male and female rotors and the housing to compensate for the machining error of the parts and the force and heat deformation during operation.

[0022] In one possible implementation, the fluid domain model constructed in step S1 includes a dynamic fluid domain model and a static fluid domain model. The dynamic fluid domain model is generated based on the rotor profile and related structural parameters, while the static fluid domain model is obtained by performing Boolean operations on the solid domain model, ensuring the spatial positional coordination between the fluid domain and the solid domain.

[0023] In one possible implementation, step S2 configures the computational fluid dynamics physics field for the fluid domain model of the screw compressor, including the following steps: Define the inlet, outlet, and wall boundary conditions of the fluid domain, and define the interface between the fluid domain and the solid domain as the thermal-fluid-solid coupling interface to achieve efficient fluid transport in the solid domain. Mesh the dynamic and static fluid domains and refine the mesh near the coupling interface to improve the calculation accuracy of the load transfer process. Based on the actual physical duration of the current operating conditions, set the corresponding simulation step size and simulation duration of the simulation process to ensure the realistic simulation of the fluid dynamic characteristics in the time domain; Based on the operating medium and operating parameters of the screw compressor, configure the relevant parameters of the computational fluid dynamics physical field.

[0024] In one possible implementation, step S2 configures the conjugate heat transfer physics field for the solid domain model of the screw compressor, including the following steps: Define the material properties of the solid domain model, including at least density, elastic modulus, Poisson's ratio, thermal diffusivity and coefficient of thermal expansion, to provide basic parameters for heat transfer calculation and structural mechanics analysis; The solid domain model is meshed to generate a solid domain mesh. The interface in the solid domain model that contacts the fluid domain is defined as the thermal-fluid-solid coupling interface, which is used to receive fluid loads. By embedding a solid domain grid into the fluid domain grid of the computational fluid dynamics physical field, conjugate heat transfer calculations are performed. The interface between the solid domain grid and the fluid domain grid is defined as the thermal-fluid-solid coupling interface, thereby realizing the synchronous calculation of the heat transfer process in the fluid domain and the solid domain and obtaining the temperature distribution of the solid structure. Configure the parameters of the conjugate heat transfer physical field according to the heat transfer analysis requirements.

[0025] In one possible implementation, step S2 configures the solid mechanical physics field for the solid domain model of the screw compressor, including the following steps: A fixed constraint is applied to the bottom of the solid domain model to simulate the actual installation state of the equipment; the bolt connection surfaces between the components of the solid domain are set to frictional contact, and the tightening effect of the bolts is simulated by beam elements and preload to ensure the realistic reproduction of the structural connection relationship; A gravity load is applied vertically to the solid domain model; an external dynamic load time history is applied, including but not limited to hydrodynamic, wind-driven, or seismic loads. The external dynamic load time history is obtained by performing an inverse Fourier transform on the response spectrum of the external dynamic load, and the time step and total duration of the external dynamic load in the time domain are consistent with the physical field of the computational fluid dynamics, so as to realize the simulation of the synergistic effect of the load in the time domain; the interface in the solid domain model that contacts the fluid domain is defined as the thermo-fluid-solid coupling interface, which is used to receive the transient force pulsating load of fluid pressure. Configure the relevant parameters of the solid mechanics physical field according to the properties of solid materials and the requirements of mechanical analysis.

[0026] In one possible implementation, step S3 establishes a thermal-fluid-structure interaction (TFI) analysis model and integrates computational fluid dynamics, conjugate heat transfer, and solid mechanics-based physical fields into the TFI analysis model, including the following steps: Build a one-way transient thermal-fluid-structure interaction analysis project and clarify the solution order and data transfer path of each physical field; Solving the computational fluid dynamics (CFD) physical field is crucial because screw compressors, as typical rotating machinery, have inherent non-uniform gaps between their internal rotors and the casing, and between the rotors themselves. Fluid leakage is inevitable during operation, and this leakage exacerbates the non-uniformity and unsteadiness of the internal temperature and pressure fields, creating a complex transient fluid-thermal environment. Therefore, it is necessary to accurately solve the CFD physical field based on the established thermal-fluid-structure interaction analysis model to provide accurate transient fluid pressure fluctuations and temperature distributions for subsequent solutions.

[0027] After the flow field solution is completed, the temperature data of the computational fluid dynamics physical field is transferred to the conjugate heat transfer physical field. At the same time, the pressure fluctuation data of the computational fluid dynamics physical field and the temperature data of the conjugate heat transfer physical field are transferred to the solid mechanics physical field in a coordinated manner. This provides accurate load input for structural dynamic response analysis and ensures the accuracy and reliability of multi-field coupled simulation.

[0028] In one possible implementation, step S4, based on the solution results of the thermo-fluid-structure interaction analysis model, determines whether the structural strength and deformation of the screw compressor meet the requirements, including the following steps: The dynamic response of a screw compressor under the combined action of internal fluid pressure load, thermal load and external dynamic load is simulated by running a thermal-fluid-structure interaction analysis model. The maximum equivalent stress of the structure is extracted from the calculation results and compared with the allowable stress of the material. If the maximum equivalent stress is less than the allowable stress of the material, the structural strength of the screw compressor is deemed to meet the requirements; otherwise, it is not. The deformation of each part of the structure was extracted from the calculation results. Based on the operating characteristics of the screw compressor, a special verification of four sets of key clearances was conducted. Please refer to [link / reference]. Figure 2 These are: the axial relative deformation between the male and female rotors and the suction end face of the housing, the axial relative deformation between the male and female rotors and the exhaust end face of the housing, the radial relative deformation between the tooth tips of the male and female rotors and the rotor cavity, and the normal relative deformation between the teeth of the male and female rotors; if each of the relevant deformation amounts is less than the corresponding set safety clearance threshold, then the deformation amount of the screw compressor is judged to meet the operating requirements; otherwise, it is not met.

[0029] The following detailed explanation of the multi-field coupling reliability simulation analysis method for screw compressors proposed in this invention is provided through specific examples, including the following steps: S1. Model Building: 1. Solid domain model construction: Based on the 3D design drawings of the screw compressor, a solid domain model is built using 3D modeling software. The core components of the model include male and female rotors, housing and bearing seats; the geometric models of secondary connecting parts such as bolts and nuts are deleted to simplify the model structure.

[0030] 2. Fluid Domain Model Construction: Based on the solid domain model, a fluid domain model is constructed by dividing the model into dynamic fluid domain and static fluid domain. Dynamic fluid domain generation: Based on rotor profile parameters (including addendum circle diameter, dedendum circle diameter, lead, number of teeth, etc.) and related structural parameters (such as rotor length, installation center distance, etc.), a dynamic fluid domain matching the motion trajectory of the male and female rotors is generated. Static fluid domain generation: Boolean operation is performed on the solid domain model to remove the space occupied by the solid domain, resulting in a static fluid domain that includes the intake and exhaust channels, ensuring that the spatial positions of the static fluid domain and the solid domain are accurately matched. S2, Physical Field Configuration: 1. Computational Fluid Dynamics (CFD) Physics Configuration: Boundary condition definition: Set the fluid domain inlet as a pressure inlet with a pressure value of atmospheric pressure (0.1MPa) and a temperature of 25℃; set the outlet as a pressure outlet with a pressure value of 0.8MPa; set the wall surface as a no-slip boundary; define the interface between the fluid domain and the solid domain (male and female rotor surfaces, inner wall of the casing) as a thermal-fluid-structure interaction interface, which is used to transfer fluid pressure and thermal load.

[0031] Mesh generation: The dynamic fluid domain mesh is generated by inputting the rotor geometry parameters and the gap between the moving and stationary parts into the mesh generation software. The static fluid domain mesh size is controlled at 3-8mm. The mesh near the coupling interface is refined, and the refined mesh size is 1-2mm to ensure the calculation accuracy of load transfer.

[0032] Simulation timing settings: Under the actual operating conditions of the compressor, the analysis time for the stable operation phase is set to 10s. In order to accurately capture the transient pressure pulsation of the fluid, the simulation step size is set to 0.001s to ensure the complete simulation of the dynamic characteristics in the time domain.

[0033] Parameter configuration: The operating medium is air.

[0034] 2. Configuration of conjugate heat transfer physical fields: Material property definition: The material is HT-250, with an elastic modulus of 160 GPa, Poisson's ratio of 0.274, and a mass density of 7000 kg / m³. 3 The coefficient of thermal expansion is 1.29 × 10⁻⁶. -5 / ℃.

[0035] Mesh generation and coupling interface definition: Tetrahedral meshes are used to divide the solid domain model, with the mesh size controlled between 3-10 mm; the interface between the solid domain and the fluid domain is defined as the thermal-fluid-solid coupling interface, which corresponds one-to-one with the coupling interface in the CFD physics field, and is used to receive the thermal and pressure loads transferred by the fluid.

[0036] Conjugate heat transfer implementation: A solid domain mesh is embedded in the fluid domain mesh of the CFD physics field, and the interface between the two is defined as the thermal-fluid-solid coupling interface. A conjugate heat transfer calculation model is set up to realize the synchronous calculation of the heat transfer process in the fluid domain and the solid domain.

[0037] Parameter configuration: The heat transfer coefficient is calculated using the default turbulent heat transfer model (k-ε model) to ensure accurate simulation of the heat transfer process.

[0038] 3. Solid mechanical physical field configuration: Constraint and contact settings: A fixed constraint is applied to the bottom of the bearing housing to simulate the actual installation state of the compressor; the bolt connection surfaces between the male and female rotors and the bearing housing, and between the housing and the bearing housing are set to frictional contact, with a friction coefficient of 0.15; beam elements are used to simulate bolts, and a preload is applied to restore the tightening effect of the bolts.

[0039] Load application: A gravity load (gravitational acceleration 9.81 m / s²) is applied vertically to the solid domain model. Considering that the compressor is installed in the workshop, the external dynamic load is mainly ground vibration. The ground vibration response spectrum is converted into the time-domain load time history through inverse Fourier transform. The load amplitude is 0.1g, the time step is 0.001s, and the total duration is 10s, consistent with the CFD physics field. The coupling interface between the solid domain and the fluid domain is set as the load receiving surface to receive the transient pressure pulsation load of the fluid.

[0040] Parameter configuration: The stress calculation adopts the von Mises equivalent stress criterion for subsequent structural strength verification.

[0041] S3, Multiphysics Coupling: 1. Create a coupled project: In ANSYS Workbench software, create a unidirectional transient thermo-fluid-structure interaction (TFL) analysis project. Set the solution order as follows: First, perform CFD physics field solution to obtain the temperature distribution and transient pressure fluctuations in the fluid domain; then, transfer the temperature data to the conjugate heat transfer physics field, and combine it with the heat transfer characteristics of the solid domain to obtain the temperature distribution in the solid domain; finally, transfer the transient pressure fluctuation data from the CFD physics field and the temperature data from the conjugate heat transfer physics field to the solid mechanics physics field to conduct structural dynamic response analysis.

[0042] 2. Coupling Interface Mapping: Utilizing the software's interface mapping function, the coupling interfaces in the CFD physical field, conjugate heat transfer physical field, and solid mechanics physical field are accurately mapped to ensure the integrity and accuracy of data transmission. Temperature data from the CFD physical field is transmitted to the corresponding interface of the conjugate heat transfer physical field through mapping, and pressure pulsation data from the CFD physical field and temperature data from the conjugate heat transfer physical field are synchronously transmitted to the corresponding interface of the solid mechanics physical field through mapping.

[0043] S4. Solution and Output: 1. Solving and Calculation: Start the coupled analysis system to perform the solving and calculation. The software will complete the thermal-fluid-structure interaction simulation in the 10-second time domain according to the set solution order and data transmission path, and obtain the stress distribution, deformation distribution and temperature distribution data of each component in the solid domain and key parts.

[0044] 2. Structural strength verification: The maximum equivalent stress in the solid domain is extracted from the calculation results, and the structural strength of the screw compressor is determined to meet the requirements.

[0045] 3. Critical gap verification: Extract the deformation of each critical part and conduct four sets of critical gap verifications: The relative deformation between the male and female rotors and the intake end face of the casing is obtained by summing the axial deformations of the rotor and the intake end face of the casing. The relative deformation between the male and female rotors and the exhaust end face of the casing is obtained by summing the axial deformations of the rotor and the exhaust end face of the casing. The relative deformation between the rotor tooth tip and the rotor cavity requires consideration of both the radial deformation of the rotor cavity and the radial deformation of the rotor tooth tip. The actual radial deformation of the rotor tooth tip is obtained by projecting the actual deformation of each point on the rotor path relative to the rotor center onto the original radial direction of the rotor. The calculation method for the actual radial deformation of the rotor cavity is similar. The relative deformation between the male and female rotor teeth requires consideration of the normal deformation of the corresponding meshing point of the male and female rotors. The normal deformation is calculated by projecting the actual deformation vector of each point on the rotor path onto the normal vector of the rotor helical surface. After calculation, the relative deformation at each position is less than the design reserved clearance value, and the equipment deformation meets the requirements.

[0046] In summary, the structural strength and deformation of this screw compressor model meet the operational requirements, and its reliability is up to standard.

[0047] Another embodiment of the present invention provides a multi-field coupling reliability simulation analysis system for screw compressors, comprising: The solid domain and fluid domain model building module is used to build the solid domain and fluid domain models of the screw compressor. The physics configuration module is used to configure computational fluid dynamics physics fields for the fluid domain model of the screw compressor, and to configure conjugate heat transfer physics fields and solid mechanical physics fields for the solid domain model of the screw compressor. The thermal-fluid-structure interaction (TFI) module is used to establish a TFI model based on computational fluid dynamics (CFD), conjugate heat transfer, and solid mechanics. It is used to simulate multi-field coupling scenarios of screw compressors and solve the CFD model. The temperature data from the CFD model is transferred to the conjugate heat transfer model, and the pressure pulsation data from the CFD model and the temperature data from the conjugate heat transfer model are transferred to the solid mechanics model. The reliability solution and judgment module is used to obtain the solution results of the thermal-fluid-structure interaction analysis model and determine whether the structural strength and deformation of the screw compressor meet the requirements.

[0048] The screw compressor multi-field coupling reliability simulation analysis system of this invention, through the coordinated work of the above modules, can realize the standardized conduct of thermal-fluid-solid multi-field coupling reliability simulation analysis of screw compressors, greatly improve the analysis efficiency and the accuracy of the results, and provide an efficient technical tool for the design optimization and reliability assessment of screw compressors.

[0049] Another embodiment of the present invention also provides an electronic device comprising: A memory that stores at least one instruction; and a processor that executes the instructions stored in the memory to implement the multi-field coupling reliability simulation analysis method for the screw compressor.

[0050] Another embodiment of the present invention provides a computer-readable storage medium storing at least one instruction, which is executed by a processor in an electronic device to implement the multi-field coupling reliability simulation analysis method for the screw compressor.

[0051] The computer program includes computer program code, which can be in the form of source code, object code, executable file, or some intermediate form. The computer-readable storage medium can include any entity or device capable of carrying the computer program code, a medium, a USB flash drive, a portable hard drive, a magnetic disk, an optical disk, a computer memory, a read-only memory, a random access memory, an electrical carrier signal, a telecommunication signal, and a software distribution medium, etc. It should be noted that the content included in the computer-readable medium can be appropriately added or removed according to the requirements of legislation and patent practice in the jurisdiction. For example, in some jurisdictions, according to legislation and patent practice, the computer-readable medium does not include electrical carrier signals and telecommunication signals. For ease of explanation, the above content only shows the parts related to the embodiments of the present invention; for specific technical details not disclosed, please refer to the method section of the embodiments of the present invention. This computer-readable storage medium is non-transitory and can be stored in storage devices formed by various electronic devices, enabling the execution process described in the method of the embodiments of the present invention.

[0052] Those skilled in the art will understand that embodiments of the present invention can be provided as methods, systems, or computer program products. Therefore, the present invention can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, the present invention can take the form of a computer program product embodied on one or more computer-usable storage media (including, but not limited to, disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0053] This invention is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of the invention. It should be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, generate instructions for implementing the flowchart illustrations and / or block diagrams. Figure 1 One or more processes and / or boxes Figure 1A device that provides the functions specified in one or more boxes.

[0054] These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing device to function in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means, which are implemented in a process Figure 1 One or more processes and / or boxes Figure 1 The function specified in one or more boxes.

[0055] These computer program instructions may also be loaded onto a computer or other programmable data processing equipment to cause a series of operational steps to be performed on the computer or other programmable equipment to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable equipment for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.

[0056] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit it. Although the present invention has been described in detail with reference to the above embodiments, those skilled in the art should understand that modifications or equivalent substitutions can still be made to the specific implementation of the present invention. Any modifications or equivalent substitutions that do not depart from the spirit and scope of the present invention should be covered within the scope of protection of the claims of the present invention.

Claims

1. A multi-field coupling reliability simulation analysis method for screw compressors, characterized in that, include: Establish solid domain and fluid domain models for screw compressors; Computational fluid dynamics physics fields are configured for the fluid domain model of the screw compressor, and conjugate heat transfer physics fields and solid mechanical physics fields are configured for the solid domain model of the screw compressor. A thermo-fluid-solid coupled analysis model is established based on the computational fluid dynamics (CFD) physical field, the conjugate heat transfer physical field, and the solid mechanics physical field. The multi-field coupled scenario of the screw compressor is simulated using the thermo-fluid-solid coupled analysis model, and the CFD physical field is solved. The temperature data of the CFD physical field is transferred to the conjugate heat transfer physical field, and the pressure pulsation data of the CFD physical field and the temperature data of the conjugate heat transfer physical field are transferred to the solid mechanics physical field in a coordinated manner. Obtain the solution results of the thermo-fluid-structure interaction analysis model to determine whether the structural strength and deformation of the screw compressor meet the requirements.

2. The multi-field coupling reliability simulation analysis method for screw compressors according to claim 1, characterized in that, In the step of establishing the solid domain model and fluid domain model of the screw compressor, the solid domain model of the screw compressor includes models related to the male and female rotors, the casing and bearing housing. The male and female rotors are a pair of meshing helical rotors that can complete the compression and transportation of the working fluid through rotation. The suction and exhaust end face gaps, tooth tip gaps and tooth gaps are reserved between the male and female rotors and the casing to compensate for the machining errors of the parts and the force and heat deformation during operation.

3. The multi-field coupling reliability simulation analysis method for screw compressors according to claim 1, characterized in that, In the step of establishing the solid domain model and fluid domain model of the screw compressor, the fluid domain model of the screw compressor includes a dynamic fluid domain model and a static fluid domain model; the dynamic fluid domain model is generated based on the rotor profile and related structural parameters, and the static fluid domain model is obtained by performing Boolean operations on the solid domain model to ensure the spatial positional coordination between the fluid domain and the solid domain.

4. The multi-field coupling reliability simulation analysis method for screw compressors according to claim 3, characterized in that, In the step of establishing the solid domain model and fluid domain model of the screw compressor, the dynamic fluid domain and the static fluid domain are meshed, and the mesh near the coupling interface is refined to improve the calculation accuracy of the load transfer process.

5. The multi-field coupling reliability simulation analysis method for screw compressors according to claim 1, characterized in that, The steps for configuring the computational fluid dynamics physics field for the fluid domain model of the screw compressor include: Define the inlet, outlet, and wall boundary conditions of the fluid domain, and define the interface between the fluid domain and the solid domain as the thermal-fluid-solid coupling interface to realize the effective transfer of fluid load to the solid domain; Based on the actual physical duration of the current operating conditions, set the corresponding simulation step size and simulation duration of the simulation process to ensure the realistic simulation of the fluid dynamic characteristics in the time domain; Based on the operating medium and operating parameters of the screw compressor, configure the relevant parameters of the computational fluid dynamics physical field.

6. The multi-field coupling reliability simulation analysis method for screw compressors according to claim 1, characterized in that, The steps for configuring conjugate heat transfer physics fields for a solid domain model of a screw compressor include: The material properties of the solid domain model are defined to provide basic parameters for heat transfer calculations and structural mechanics analysis; the material properties of the solid domain model include density, elastic modulus, Poisson's ratio, thermal diffusivity, and coefficient of thermal expansion. The solid domain model is meshed to generate a solid domain mesh. The interface in the solid domain model that contacts the fluid domain is defined as the thermal-fluid-solid coupling interface, which is used to receive fluid loads. By embedding a solid domain grid into the fluid domain grid of the computational fluid dynamics physical field, conjugate heat transfer calculations are performed. The interface between the solid domain grid and the fluid domain grid is defined as the thermal-fluid-solid coupling interface, thereby realizing the synchronous calculation of the heat transfer process in the fluid domain and the solid domain and obtaining the temperature distribution of the solid structure. Configure the parameters of the conjugate heat transfer physical field according to the heat transfer analysis requirements.

7. The multi-field coupling reliability simulation analysis method for screw compressors according to claim 1, characterized in that, The steps for configuring solid mechanical physics fields for a solid domain model of a screw compressor include: A fixed constraint is applied to the bottom of the solid domain model to simulate the actual installation state of the equipment; the bolt connection surfaces between the components of the solid domain are set to frictional contact, and the tightening effect of the bolts is simulated by beam elements and preload to ensure the realistic reproduction of the structural connection relationship; A gravity load is applied vertically to the solid domain model; an external dynamic load time history is applied, which is obtained by performing an inverse Fourier transform on the response spectrum of the external dynamic load, and the time step and total duration of the external dynamic load in the time domain are consistent with the physical field of the computational fluid dynamics, so as to realize the simulation of the synergistic effect of the load in the time domain; the interface in the solid domain model that contacts the fluid domain is defined as the thermo-fluid-solid coupling interface, which is used to receive the transient force pulsating load of fluid pressure; Configure the relevant parameters of the solid mechanics physical field according to the properties of solid materials and the requirements of mechanical analysis.

8. The multi-field coupling reliability simulation analysis method for screw compressors according to claim 1, characterized in that, The steps for obtaining the solution results of the thermo-fluid-structure interaction analysis model and determining whether the structural strength and deformation of the screw compressor meet the requirements include: simulating the dynamic response of the screw compressor under the combined action of internal fluid pressure load, thermal load, and external dynamic load during operation; extracting the maximum equivalent stress of the structure from the calculation results, comparing the maximum equivalent stress with the allowable stress of the material, and determining that the structural strength of the screw compressor meets the requirements if the maximum equivalent stress is less than the allowable stress of the material; otherwise, it does not; extracting the deformation of each part of the structure from the calculation results and performing clearance checks, and determining that the deformation of the screw compressor meets the operating requirements if all relevant deformations are less than the corresponding set safety clearance threshold; otherwise, it does not.

9. The multi-field coupling reliability simulation analysis method for screw compressors according to claim 1, characterized in that, In the step of extracting the deformation of each part of the structure from the calculation results and performing gap verification, the objects of verification include the axial relative deformation of the male and female rotors and the intake end face of the housing, the axial relative deformation of the male and female rotors and the exhaust end face of the housing, the radial relative deformation of the male and female rotor tooth tips and the rotor cavity, and the normal relative deformation between the male and female rotor teeth.

10. A multi-field coupling reliability simulation analysis system for screw compressors, characterized in that, include: The solid domain and fluid domain model building module is used to build the solid domain and fluid domain models of the screw compressor. The physics configuration module is used to configure computational fluid dynamics physics fields for the fluid domain model of the screw compressor, and to configure conjugate heat transfer physics fields and solid mechanical physics fields for the solid domain model of the screw compressor. The thermal-fluid-structure interaction (TFI) module is used to establish a TFI model based on computational fluid dynamics (CFD), conjugate heat transfer, and solid mechanics. It is used to simulate multi-field coupling scenarios of screw compressors and solve the CFD model. The temperature data from the CFD model is transferred to the conjugate heat transfer model, and the pressure pulsation data from the CFD model and the temperature data from the conjugate heat transfer model are transferred to the solid mechanics model. The reliability solution and judgment module is used to obtain the solution results of the thermal-fluid-structure interaction analysis model and determine whether the structural strength and deformation of the screw compressor meet the requirements.

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