CN-121543304-B - Simulation method of multistage supercritical carbon dioxide centrifugal compressor

CN121543304BCN 121543304 BCN121543304 BCN 121543304BCN-121543304-B

Abstract

The application discloses a simulation method of a multistage supercritical carbon dioxide centrifugal compressor, which belongs to the field of centrifugal compressor simulation and comprises the steps of determining first physical property data of a compressed carbon dioxide working medium in the compressor according to entropy boundary conditions of the compressor, determining second physical property data of the carbon dioxide working medium in the compressor, determining initial flow field data of the carbon dioxide working medium in the compressor based on the first physical property data and the second physical property data, determining third physical property data of the carbon dioxide working medium in the compressor according to the initial flow field data, and determining simulated flow field data of the carbon dioxide working medium in the compressor based on the third physical property data and the second physical property data. The application realizes the accurate characterization of the flow field characteristics under the complex working condition, reduces the adverse effect caused by too high calculation complexity, and ensures that the simulation process is close to the actual running state and has higher simulation efficiency and stability.

Inventors

WANG ZHIHENG
CHEN YUGUANG
WANG MINGYI
XI GUANG

Assignees

西安交通大学

Dates

Publication Date: 20260505
Application Date: 20260115

Claims (10)

1. A method for simulating a multistage supercritical carbon dioxide centrifugal compressor, comprising: Determining first physical property data of a compressed carbon dioxide working medium in a compressor according to an entropy boundary condition of the compressor, and determining second physical property data of the carbon dioxide working medium in the compressor, wherein the first physical property data is used for representing density distribution, viscosity distribution and sound speed distribution of the carbon dioxide working medium in the compressor when pressure data formed by the carbon dioxide working medium in the compressor is taken as a unitary independent variable, and the second physical property data is used for representing temperature distribution, entropy distribution and minor phase mass fraction distribution of the carbon dioxide working medium in the compressor when pressure-static enthalpy data formed by the carbon dioxide working medium in the compressor is taken as a binary independent variable; Determining initial flow field data of the carbon dioxide working medium in the compressor based on the first physical property data and the second physical property data, wherein the flow field data comprises speed distribution, pressure distribution and static enthalpy distribution of the carbon dioxide working medium under the second physical property data; Determining third physical data of the carbon dioxide working medium in the compressor according to the initial flow field data, wherein the third physical data is used for representing density distribution, viscosity distribution and sound velocity distribution of the carbon dioxide working medium in the compressor under the constraint condition of target pressure-entropy value; and determining flow field data simulated in the compressor by the carbon dioxide working medium based on the third physical data and the second physical data.
2. The method for simulating a multistage supercritical carbon dioxide centrifugal compressor according to claim 1, wherein said determining first physical property data of a compressed carbon dioxide working medium in said compressor according to an entropy boundary condition of the compressor comprises: Determining a plurality of first observation positions in the compressor according to a first pressure interval step size by taking an entropy value at an inlet of the compressor as a boundary condition; And determining a density value, a viscosity value and an acoustic velocity value of the carbon dioxide working medium at each first observation position to form the first physical property data.
3. The method of multistage supercritical carbon dioxide centrifugal compressor simulation of claim 1, wherein said determining second physical data of the carbon dioxide working fluid in the compressor comprises: Determining a plurality of second observation positions in the compressor according to a second pressure interval step length and a static enthalpy interval step length; and determining a temperature value, an entropy value and a minor phase mass fraction value of the carbon dioxide working medium at each second observation position to form the second object property data.
4. The method of multistage supercritical carbon dioxide centrifugal compressor simulation of claim 1, wherein said determining initial flow field data for the carbon dioxide working fluid in the compressor based on the first physical property data and the second physical property data comprises: determining a plurality of reference surfaces in the fluid flowing direction of the compressor according to the section step length, and determining a plurality of target reference surfaces in the reference surfaces, wherein the target reference surfaces are respectively used for calibrating the inlet position of the compressor or the fluid dynamic and static boundary position in the compressor; determining a target first static enthalpy parameter set of each target reference surface, and determining a first speed parameter set and a first pressure parameter set of each position in the compressor according to iterative solution of a first boundary condition and a second boundary condition in an imported parameter solver, wherein the first boundary condition is imported into the parameter solver through linear interpolation of the first physical property data; And determining a first static enthalpy parameter set of each position in the compressor according to all the first speed parameter sets and all the target first static enthalpy parameter sets, and generating initial flow field data according to all the first speed parameter sets, all the first pressure parameter sets and all the first static enthalpy parameter sets.
5. The method of multistage supercritical carbon dioxide centrifugal compressor simulation of claim 1, wherein said determining third physical data of said carbon dioxide working fluid in said compressor from initial said flow field data comprises: Determining a plurality of target positions in the compressor under the initial flow field data respectively, and determining a pressure value and an entropy value corresponding to each target position respectively; Determining a target pressure-entropy reference line formed under the target pressure-entropy constraint condition according to each corresponding set of the pressure values and the entropy values, and determining a plurality of third observation positions in the compressor according to a third pressure interval step length; And determining a density value, a viscosity value and an acoustic velocity value of the carbon dioxide working fluid at each third observation position to form the third physical data.
6. The method of multistage supercritical carbon dioxide centrifugal compressor simulation of claim 1, wherein said determining flow field data for simulation of the carbon dioxide working fluid in the compressor based on the third and second physical data comprises: determining a plurality of reference surfaces in the fluid flowing direction of the compressor according to the section step length, and determining a plurality of target reference surfaces in the reference surfaces, wherein the target reference surfaces are respectively used for calibrating the inlet position of the compressor or the fluid dynamic and static boundary position in the compressor; Determining a target second static enthalpy parameter set of each target reference surface, and determining a second speed parameter set and a second pressure parameter set of each position in the compressor according to iterative solution of a third boundary condition and a second boundary condition in an imported parameter solver, wherein the third boundary condition is imported into the parameter solver through linear interpolation of third object data; And determining a second static enthalpy parameter set of each position in the compressor according to all second speed parameter sets and all target second static enthalpy parameter sets, and generating simulated flow field data according to all second speed parameter sets, all second pressure parameter sets and all second static enthalpy parameter sets.
7. A device for simulating a multistage supercritical carbon dioxide centrifugal compressor, comprising: The physical property input module is used for determining first physical property data of the compressed carbon dioxide working medium in the compressor according to the entropy boundary condition of the compressor and determining second physical property data of the carbon dioxide working medium in the compressor; the first physical property data are used for representing density distribution, viscosity distribution and sound velocity distribution of the carbon dioxide working medium formed in the compressor under the condition that pressure data formed in the compressor by the carbon dioxide working medium are used as unitary independent variables; the second property data is used for representing temperature distribution, entropy distribution and minor phase mass fraction distribution formed in the compressor by the carbon dioxide working medium under the condition that pressure-static enthalpy data formed in the compressor by the carbon dioxide working medium is taken as a binary independent variable; The initial flow field module is used for determining initial flow field data of the carbon dioxide working medium in the compressor based on the first physical property data and the second physical property data, wherein the flow field data comprises speed distribution, pressure distribution and static enthalpy distribution of the carbon dioxide working medium under the second physical property data; The physical property correction module is used for determining third physical property data of the carbon dioxide working medium in the compressor according to the initial flow field data, wherein the third physical property data is used for representing density distribution, viscosity distribution and sound velocity distribution formed by the carbon dioxide working medium in the compressor under the constraint condition of target pressure-entropy value; and the flow field simulation module is used for determining flow field data simulated by the carbon dioxide working medium in the compressor based on the third physical data and the second physical data.
8. A computer readable storage medium, characterized in that the computer readable storage medium has stored thereon a computer program which, when executed by a processor, implements a method of multistage supercritical carbon dioxide centrifugal compressor simulation according to any of claims 1 to 6.
9. An electronic device comprising a processor, a memory and a computer program stored on the memory and executable on the processor, which when executed by the processor performs the steps of the method of multi-stage supercritical carbon dioxide centrifugal compressor simulation as claimed in any one of claims 1 to 6.
10. A computer program product, characterized in that it has stored thereon a computer program which, when executed by a processor, implements the steps of the method of multistage supercritical carbon dioxide centrifugal compressor simulation according to any one of claims 1 to 6.

Description

Simulation method of multistage supercritical carbon dioxide centrifugal compressor Technical Field The application belongs to the field of centrifugal compressor simulation, and particularly relates to a method, a device, a storage medium, equipment and a computer program product for simulating a multistage supercritical carbon dioxide centrifugal compressor. Background Along with the development of energy systems to high efficiency and low carbon, supercritical carbon dioxide circulation gradually becomes an important research object of novel power generation and refrigeration systems due to good thermodynamic performance and environmental adaptability. In the circulating system, a multistage supercritical carbon dioxide centrifugal compressor is used as key equipment, and the running state of the multistage supercritical carbon dioxide centrifugal compressor directly influences the overall efficiency and stability of the system. Therefore, numerical simulation analysis is carried out on the compressor, internal flow field characteristics are obtained, design parameters are optimized, and the method becomes an important means for improving equipment performance. The existing centrifugal compressor simulation method generally depends on a general hydrodynamic solver and combines a physical property database to obtain the thermophysical property parameters of working media. In a specific implementation process, a physical property table is generally established, parameters such as pressure, temperature and the like are used as input conditions, physical property data such as density, viscosity, sound velocity, heat conductivity coefficient and specific heat capacity are further obtained, the physical property data are used as key inputs of a solver, and a geometric model and boundary conditions of the compressor are combined to generate flow field distribution inside the compressor through solving a control equation. Although the method can reflect the flowing state of the compressor to a certain extent, the method has limited adaptability to complex working conditions, and can not ensure calculation convergence, and meanwhile, the simulation solution needs to consume high calculation force and calculation time, and can not adapt to further experiment speed requirements. Disclosure of Invention The application aims to provide a method, a device, a storage medium, equipment and a computer program product for simulating a multistage supercritical carbon dioxide centrifugal compressor, which at least solve the problems of poor convergence and slow solving speed caused by overlarge simulation calculation amount of the carbon dioxide centrifugal compressor. In a first aspect, an embodiment of the present application discloses a method for simulating a multistage supercritical carbon dioxide centrifugal compressor, including: Determining first physical property data of a compressed carbon dioxide working medium in a compressor according to an entropy boundary condition of the compressor, and determining second physical property data of the carbon dioxide working medium in the compressor, wherein the first physical property data is used for representing density distribution, viscosity distribution and sound speed distribution of the carbon dioxide working medium in the compressor when pressure data formed by the carbon dioxide working medium in the compressor is taken as a unitary independent variable, and the second physical property data is used for representing temperature distribution, entropy distribution and minor phase mass fraction distribution of the carbon dioxide working medium in the compressor when pressure-static enthalpy data formed by the carbon dioxide working medium in the compressor is taken as a binary independent variable; Determining initial flow field data of the carbon dioxide working medium in the compressor based on the first physical property data and the second physical property data, wherein the flow field data comprises speed distribution, pressure distribution and static enthalpy distribution of the carbon dioxide working medium under the second physical property data; Determining third physical data of the carbon dioxide working medium in the compressor according to the initial flow field data, wherein the third physical data is used for representing density distribution, viscosity distribution and sound velocity distribution of the carbon dioxide working medium in the compressor under the constraint condition of target pressure-entropy value; and determining flow field data simulated in the compressor by the carbon dioxide working medium based on the third physical data and the second physical data. In a second aspect, the embodiment of the application also discloses a device for simulating the multistage supercritical carbon dioxide centrifugal compressor, which comprises: The physical property input module is used for determining first physical property data of the compressed car