CN115289051B - Design Method of Stator Structure of Centrifugal Compressor - Google Patents

Abstract

The present invention provides a design method for a centrifugal compressor stator structure, including determining independent variable parameters according to the meridian profile of a bend and a returner, determining the sample space of the independent variable parameters based on an experimental design method and performing computational fluid dynamics calculations, obtaining experimental data for each group of independent variable parameters, and obtaining the dimensionless value range of the independent variable parameters through analysis to complete the design of the centrifugal compressor stator structure. The design method for a centrifugal compressor stator structure provided by the present invention can quickly obtain a bend and returner meridian structure with good aerodynamic performance by parameterizing the meridian profile, does not rely on the experience of the designer, greatly shortens the development cycle of the centrifugal compressor, and provides a theoretical basis for the research and development of high-performance and large-flow coefficient centrifugal compressor products.

Description

Design Method of Stator Structure of Centrifugal Compressor

Technical Field

The invention relates to the technical field of centrifugal compressors, and in particular to a design method for a stator structure of a centrifugal compressor.

Background Art

The structure of a multi-stage centrifugal compressor is mainly divided into a rotor part and a stator part, wherein the stator part mainly includes a series of non-rotating parts such as the casing, diffuser, bend, returner, volute and sealing assembly. The bend and returner in the stator part are important components of a multi-stage centrifugal compressor. They are mainly used to guide the airflow to the next stage and play a key role in connecting the upper and lower stages. However, the bend and returner are not as important as the impeller and diffuser in structural design. While guiding the airflow, the bend and returner also need to limit the circumferential component velocity of the airflow in the flow channel, reduce flow losses, and ensure that no large vortices are generated. The impact of their performance on the current stage and the next stage cannot be ignored. Therefore, when the performance improvement of the impeller and diffuser is becoming increasingly limited, the structural design of the bend and returner has an important impact on the aerodynamic performance of the centrifugal compressor.

The existing design methods for bends and returners mainly improve the aerodynamic performance of the stator part by finding the change pattern of the cross-sectional areas of the two and controlling the uniform change of the flow channel cross-sectional area as much as possible. This design method has a long cycle, relies too much on the designer's work experience, and the final designed structure is often not the optimal solution.

Summary of the invention

In view of the above-mentioned shortcomings of the prior art, the present invention provides a design method for the stator structure of a centrifugal compressor, which solves the problems in the prior art of long design cycle of bends and returners in centrifugal compressors, reliance on designer experience, and poor design effect.

The present invention provides a design method for a centrifugal compressor stator structure, comprising:

Determining the independent variable parameters of the meridian profile according to the meridian profiles of the bend and the returner;

Acquire multiple groups of the independent variable parameters, and determine the sample space of the independent variable parameters based on an experimental design method;

Perform computational fluid dynamics calculations on each set of the independent variable parameters in the sample space to obtain test data of the centrifugal compressor simulation stage under each set of the independent variable parameters;

The test data are analyzed to obtain a dimensionless value range of the independent variable parameter, and the stator structure of the centrifugal compressor is designed based on the dimensionless value range.

Further, the independent variable parameters include the returner disk side radius, the returner inlet width, the returner disk side tilt angle, the returner cover side tilt angle, the returner outlet disk side radius and the distance between the returner and the axis; the independent variable parameters of the meridian profile are determined according to the meridian profile of the bend and the returner, including:

The meridian profile is divided into a straight line segment and an arc segment according to the geometric structure of the meridian profile, wherein the straight line segment includes the returner disc side profile, the returner cover side profile and the returner outlet disc side profile; the arc segment includes the returner disc side curve profile, the returner cover side curve profile, the returner outlet disc side curve profile and the returner outlet cover side curve profile;

Determine the return disk side radius based on the return disk side curve profile;

Determine the return inlet width based on the return cover side curve profile and the return plate side curve profile;

Determine the inclination angle of the return disk side based on the tangency between the return disk side profile line and the return disk side curve profile line;

Determine the inclination angle of the return cover side based on the tangency between the return cover side profile line and the return cover side curve profile line;

Determine the return outlet disk side radius based on the return outlet disk side curve profile being tangent to the return disk side profile and the return outlet disk side profile respectively;

Based on the curve profile of the return flow device outlet cover side, the distance between the return flow device and the axis is determined.

Furthermore, after determining the independent variable parameter of the meridian profile according to the meridian profile of the bend and the returner, the method further includes:

Calculate the coordinates of the intersection points of each segment of the profile in the straight line segment and the coordinates of the center of each segment of the curved profile in the arc segment according to the geometric structure of the meridian profile;

Establishing a function equation based on the intersection coordinates and the circle center coordinates, wherein the independent variable of the function equation is the independent variable parameter;

By interpolation operation, each segment of the straight line segment and each segment of the curved line segment in the arc segment are equally divided to obtain the coordinates of each interpolation point;

The coordinates of the interpolation points are integrated with the functional equation to obtain a parameterized model of the meridian line.

Furthermore, the experimental design method is any one of a full factorial design method, an orthogonal design method and a uniform design method.

Furthermore, the obtaining of multiple groups of independent variable parameters and determining the sample space of the independent variable parameters based on an experimental design method includes:

An orthogonal design method is adopted, based on the uniform dispersion principle, to determine the sample space of the independent variable parameters among multiple groups of the independent variable parameters, wherein the sample space includes at least three groups of the independent variable parameters.

Furthermore, the test data is analyzed to obtain the dimensionless value range of the independent variable parameter, including:

Establishing an orthogonal table of test schemes based on the test data;

Obtain the change trend of the independent variable parameter with respect to the test data according to the orthogonal table of the test scheme, and draw a trend graph;

According to the trend graph, some of the independent variable parameters are selected for modeling and calculation to determine the dimensionless value range of the independent variable parameters.

Furthermore, the test data includes aerodynamic performance and flow field information of a centrifugal compressor model stage, the aerodynamic performance includes the variable efficiency of the centrifugal compressor, and the flow field information includes the uniformity of the flow field at the return flow device outlet.

Furthermore, the parameters of the meridian profile include the diffuser outlet width, and the dimensionless parameters include the ratio of the return disk side radius to the diffuser outlet width, the ratio of the return inlet width to the diffuser outlet width, the ratio of the return disk side radius to the diffuser outlet width, the ratio of the distance between the returner and the axis to the diffuser outlet width, the return disk side inclination angle and the return cover side inclination angle.

Furthermore, the design of the stator structure of the centrifugal compressor based on the dimensionless value range includes:

Selecting a value of the dimensionless parameter within the dimensionless value range;

Obtaining a value of the independent variable parameter based on the value of the dimensionless parameter;

The meridian profiles of the bend and the returner are determined according to the values of the independent variable parameters, thereby completing the design of the stator structure of the centrifugal compressor.

Further, after completing the design of the stator structure of the centrifugal compressor based on the dimensionless value range, the method further includes:

Computational fluid dynamics calculations are performed on the aerodynamic model of the centrifugal compressor, and experimental verification is performed to obtain experimental data.

The design method of the stator structure of a centrifugal compressor provided by the present invention determines key independent variable parameters according to the meridian profiles of the bends and the reflow returner in the stator structure, then optimizes and calculates the independent variable parameters, simulates and analyzes the influence of the changes in the independent variable parameters on the aerodynamic performance of the analog stage of the centrifugal compressor, and then obtains the optimal value range of the independent variable parameters, and completes the design of the stator structure of the centrifugal compressor. This method parameterizes the meridian profiles to quickly obtain the meridian structures of the bends and the reflow returner with good aerodynamic performance, does not rely on the experience of the designers, greatly shortens the development cycle of the centrifugal compressor, and provides a theoretical basis for the research and development of high-performance and large-flow coefficient centrifugal compressor products.

Other features and advantages of the present invention will be described in the following description, and partly become apparent from the description, or understood by practicing the present invention. The purpose and other advantages of the present invention can be realized and obtained by the structures particularly pointed out in the written description, claims, and drawings.

The technical solution of the present invention is further described in detail below through the accompanying drawings and embodiments.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings are used to provide a further understanding of the present invention and constitute a part of the specification. Together with the embodiments of the present invention, they are used to explain the present invention and do not constitute a limitation of the present invention. In the accompanying drawings:

FIG1 is a flow chart of a design method for a centrifugal compressor stator structure;

FIG. 2 is a schematic diagram of the meridian line structure of the bend and returner in the stator structure of a centrifugal compressor.

In the figure:

r1, the radius of the return flow plate; r3, the radius of the return flow plate at the outlet; b4, the outlet width of the diffuser; b5, the inlet width of the return flow; R8, the distance between the return flow and the axis; α1, the tilt angle of the return flow plate; α2, the tilt angle of the return flow cover.

DETAILED DESCRIPTION

In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as limiting the present invention.

In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features. In the description of the present invention, the meaning of "plurality" is two or more, unless otherwise clearly and specifically defined.

In the present invention, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be an indirect connection through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

The present invention provides a design method for a stator structure of a centrifugal compressor, wherein the stator structure includes a bend and a return flow device, see Figures 1 and 2, including first determining the independent variable parameters of the meridian line according to the meridian line of the bend and the return flow device, secondly obtaining multiple groups of independent variable parameters, determining the sample space of the independent variable parameters based on an experimental design method, and then performing computational fluid dynamics calculations on each group of independent variable parameters in the sample space to obtain test data of a centrifugal compressor simulation stage under each group of independent variable parameters, and finally analyzing the test data to obtain a dimensionless value range of the independent variable parameters, and completing the design of the stator structure of the centrifugal compressor based on the dimensionless value range.

The design method of the stator structure of a centrifugal compressor provided by the present invention determines key independent variable parameters according to the meridian profiles of the bends and the reflow returner in the stator structure, then optimizes and calculates the independent variable parameters, simulates and analyzes the influence of the changes in the independent variable parameters on the aerodynamic performance of the analog stage of the centrifugal compressor, and then obtains the optimal value range of the independent variable parameters, and completes the design of the stator structure of the centrifugal compressor. This method parameterizes the meridian profiles to quickly obtain the meridian structures of the bends and the reflow returner with good aerodynamic performance, does not rely on the experience of the designers, greatly shortens the development cycle of the centrifugal compressor, and provides a theoretical basis for the research and development of high-performance and large-flow coefficient centrifugal compressor products.

It should be noted that this application is only for large flow coefficients, specifically The centrifugal compressor model stage stationary parts of the meridian lines of the bends and the return flow device were studied and optimized, but the return flow device blades were not studied in depth, and the blade shape used in mature return flow device products was directly adopted.

Furthermore, the independent variable parameters include the radius r1 of the returner disk side, the returner inlet width b5, the returner disk side inclination angle α1, the returner cover side inclination angle α2, the returner outlet disk side radius r3 and the distance R8 between the returner and the axis; the independent variable parameters of the meridian line are determined according to the meridian line of the curve and the returner, including first dividing the meridian line into straight segments and arc segments according to the geometric structure of the meridian line, wherein the straight segment includes the returner disk side line, the returner cover side line and the returner outlet disk side line; the arc segment includes the returner disk side curve line, the returner cover side curve line, the returner outlet disk side curve line and the returner The outlet cover side curve profile, and then determine the return disk side radius r1 based on the return disk side curve profile, determine the return inlet width b5 based on the return cover side curve profile, determine the return disk side inclination angle α1 based on the return disk side profile being tangent to the return disk side curve profile, determine the return cover side inclination angle α2 based on the return cover side profile being tangent to the return cover side curve profile, determine the return outlet disk side radius r3 based on the return disk outlet side curve profile being tangent to the return disk side profile and the return outlet disk side profile respectively, and determine the distance R8 between the returner and the axis based on the return outlet cover side curve profile.

In this embodiment, the structure of the meridian line is divided into multiple groups of straight line segments and arc segments, and the geometric parameters are determined according to the shape of each segment, and the geometric parameters are classified. The geometric parameters that cannot be derived from the remaining geometric parameters are key geometric parameters, that is, the independent variable parameters in this application, and the geometric parameters that can be derived from the remaining geometric parameters are defined as non-key geometric parameters; referring to the structure of the meridian line of the bend and the return flow device in Figure 2, the relationship between the independent variable parameters and the meridian line structure can be obtained; first, since the inlet position of the bend is unchanged, the diffuser outlet width b4 is the initial position confirmation parameter, which is determined by the impeller and diffuser of the centrifugal compressor model stage, and the change of the disk side radius r1 of the return flow device disk side radius can change the return flow device disk side bend. The returner inlet width b5 can change the returner cover side curve line and the returner disc side curve line; since the returner disc side line and the returner cover side line are tangent to the returner disc side curve line and the returner cover side curve line respectively, changing the returner disc side inclination angle α1 and the returner cover side inclination angle α2 can affect the returner disc side line and the returner cover side line; since the height of the returner outlet disc side line is limited to a constant value by the shaft diameter, and since the returner outlet disc side curve line is tangent to the returner disc side line and the returner outlet disc side line respectively, changing the returner outlet disc side radius r3 can affect the returner outlet disc side curve line; and the distance R8 between the returner and the axis affects the returner outlet cover side curve line. The meridian line of the curve and the returner can be determined by six independent variable parameters.

Furthermore, after determining the independent variable parameters of the meridian profile according to the meridian profile of the bend and the returner, it also includes first calculating the coordinates of the intersection points of each profile in the straight segment and the coordinates of the center of each curved profile in the arc segment according to the geometric structure of the meridian profile, and then establishing a function equation based on the coordinates of the intersection points and the coordinates of the center of the circle, wherein the independent variable of the function equation is the independent variable parameter, and then the profile of each profile in the straight segment and the curved profile of each profile in the arc segment are divided equally by interpolation operation to obtain the coordinates of each interpolation point, and finally the coordinates of the interpolation point are integrated with the function equation to obtain the parameterized model of the meridian profile. In this embodiment, the coordinates of the intersection points of the profile in each straight segment and the center of each arc segment are calculated by the geometric relationship of the meridian profile, and are expressed by the function equation, the independent variable in the function equation is the independent variable parameter, each segment is divided equally by interpolation and the coordinates of the interpolation points are obtained and integrated, and finally the parameterization of the meridian profile is realized, laying a foundation for the subsequent computational fluid dynamics calculation of the independent variable parameter sample.

Specifically, in the above embodiments, the experimental design method is any one of the full factorial design method, the orthogonal design method and the uniform design method. In the present embodiment, the experimental design method (Design Of Experiments, DOE) is an effective method for analyzing the effects of multiple influencing factors on target parameters. It is based on probability theory and mathematical statistics, and can economically and scientifically formulate experimental plans. This method has been widely used in many fields such as physics and sociology. There are three commonly used experimental design methods, namely the full factorial design method, the orthogonal design method and the uniform design method. In the present application, there are up to six independent variable parameters, and each parameter change will affect the meridian profile of the bend and the return flow device, and then affect the aerodynamic performance of the centrifugal compressor. Therefore, it has multiple influencing factors and is suitable for using the experimental design method to determine the sample space of the independent variable parameters.

Further, multiple groups of independent variable parameters are obtained, and the sample space of the independent variable parameters is determined based on the experimental design method, including using the orthogonal design method, based on the principle of uniform dispersion, to determine the sample space of the independent variable parameters in multiple groups of independent variable parameters, wherein the sample space includes at least three groups of independent variable parameters. In this embodiment, the orthogonal design method is to select some representative points from the comprehensive test according to the principle of uniform dispersion in all experimental design methods according to orthogonality for testing. These representative points have the characteristics of uniform dispersion, neatness and comparability, and can analyze the effect of influencing factors on target parameters, which is suitable for situations with many influencing factors and value levels. The independent variable parameter angle of the application as an influencing factor can also take many values, so it is suitable for using the orthogonal design method to study the influence of each independent variable parameter in the bend and the return flow device meridian line on the performance of the centrifugal compressor. The orthogonal design method can also handle the situation where there are interactions between multiple groups of influencing factors, and the sample space finally obtained includes three or more groups of independent variable parameters.

Further, the test data is analyzed to obtain the dimensionless value range of the independent variable parameter, including first establishing an orthogonal table of the test scheme based on the test data, then obtaining the change trend of the independent variable parameter for the test data according to the orthogonal table of the test scheme, and drawing a trend graph, and finally selecting some independent variable parameters according to the trend graph for modeling and calculation, and determining the dimensionless value range of the independent variable parameter. In this embodiment, since the orthogonal design method is used to obtain the sample space, and the main tool of the orthogonal design method is the orthogonal table, after obtaining the test data, the test data is sorted, and the orthogonal table of the test scheme is established, and the test results are analyzed by the orthogonal table of the test scheme, and the intensity and directionality of the influence of each independent variable parameter on the aerodynamic performance of the centrifugal compressor after the numerical change are obtained, and the trend graph between the change of the independent variable parameter and the change of the aerodynamic performance of the centrifugal compressor is drawn according to the above content, and the new independent variable parameter is selected in the trend graph and modeled and calculated, and finally the area range of the centrifugal compressor with higher aerodynamic performance is determined. The efficiency of the centrifugal compressor simulation stage obtained by the above method is improved by more than 1% compared with the existing centrifugal compressor.

Specifically, in the above embodiment, the test data includes the aerodynamic performance and flow field information of the centrifugal compressor model level, the aerodynamic performance includes the variable efficiency of the centrifugal compressor, and the flow field information includes the uniformity of the flow field at the outlet of the reflow device. In this embodiment, the test is carried out by changing the independent variable parameters, and the test data reflects the aerodynamic performance and flow field information of the centrifugal compressor model level. Specifically, the flow field information includes the uniformity of the flow field at the outlet of the reflow device, and the aerodynamic performance includes the variable efficiency of the centrifugal compressor. The variable efficiency is the ratio of the variable compression work to the total power in the centrifugal compressor, which is usually 80%-85%.

Specifically, in the above embodiment, the parameters of the meridian profile include the diffuser outlet width b4, and the dimensionless parameters include the ratio of the returner disk side radius r1 to the diffuser outlet width b4, the ratio of the returner inlet width b5 to the diffuser outlet width b4, the ratio of the returner outlet disk side radius r3 to the diffuser outlet width b4, the ratio of the returner to the axis distance R8 to the diffuser outlet width b4, the returner disk side inclination angle α1 and the returner cover side inclination angle α2. In this embodiment, the expression that expresses a physical derived quantity by the product of the power of several basic quantities is called the dimension formula of the physical quantity, or dimension for short. It is an expression expressed by the basic physical quantity unit after the unit system is selected. All dimensional physical quantities can be dimensionless. In this application, since the diffuser outlet width b4 is a constant, the dimensionless parameters of each independent variable parameter can be converted based on the diffuser outlet width b4. Specifically, r1/b4: 0.70-0.81; r3/b4: 2.3-2.79; b5/b4: 1.02-1.16; r8/b4: 1.53-2.26; α2: 0°-6°; α3: 0°-4°; for the flow coefficient For the bends and returners in the stationary parts of the centrifugal compressor, the value of r1/b4 decreases with the increase of the flow coefficient, that is, the larger the flow coefficient, the more the value tends to the minimum value; the values of r3/b4, b5/b4, and r8/b4 increase with the increase of the flow coefficient, that is, the larger the flow coefficient, the more the value tends to the maximum value.

Furthermore, the design of the stator structure of the centrifugal compressor is completed based on the dimensionless value range, including first selecting the value of the dimensionless parameter within the dimensionless value range, then obtaining the value of the independent variable parameter based on the value of the dimensionless parameter, and finally determining the meridian profile of the bend and the return according to the value of the independent variable parameter to complete the design of the stator structure of the centrifugal compressor. In this embodiment, the value of the dimensionless parameter is selected within the obtained dimensionless value range. Since the value of the dimensionless parameter is positively correlated with the independent variable parameter, the value of the independent variable parameter can be obtained, and the meridian profile of the bend and the return can be obtained through the value of the independent variable parameter, and the stator structure of the final centrifugal compressor is determined according to the meridian profile.

Specifically, in the above embodiment, after the design of the stator structure of the centrifugal compressor is completed based on the dimensionless value range, it also includes performing computational fluid dynamics calculations on the aerodynamic model of the centrifugal compressor as a whole, and performing experimental verification to obtain experimental data. In this embodiment, after the design of the stator structure of the centrifugal compressor is completed, computational fluid dynamics calculations are continued to be performed on the aerodynamic model of the centrifugal compressor as a whole with the designed structure, and auxiliary experiments are performed to verify and obtain various test data, so as to accumulate experience for the subsequent design of large-flow centrifugal compressors.

The specific embodiment of the centrifugal compressor stator structure designed by the design method of the centrifugal compressor stator structure provided by the present application is as follows:

The convection coefficient In the design process of the bend and returner meridian profile in the stationary parts of the centrifugal compressor model stage, the diffuser outlet width b4 is known, the value range of r1/b4 is: 0.73~0.78; the value range of r3/b4 is: 0.42~2.69; the value range of b5/b4 is: 1.05~1.14; the value range of r8/b4 is: 1.99~2.19. According to computational fluid dynamics (CFD) calculation, the model stage overall efficiency fluctuates within 5% within this value range, and the optimal solution increases the overall efficiency of the original structure from 85.2% to 86.3%. The following table shows the dimensionless value comparison of key geometric parameters under the original structure and the application of the research results of this patent.

r1/b4 r3/b4 α2 α3 b5/b4 r8/b4 This application 0.75 2.48 0 4 1.09 2.12 Original structure 0.63 2.37 6 0 1 4.16

Obviously, those skilled in the art can make various changes and modifications to the present invention without departing from the spirit and scope of the present invention. Thus, if these modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalents, the present invention is also intended to include these modifications and variations.

Claims (9)

1. A method of designing a stator structure of a centrifugal compressor, wherein the stator structure includes a bend and a return, comprising:

Determining the independent variable parameters of the meridian line according to the meridian lines of the curve and the reflux device;

Acquiring a plurality of groups of independent variable parameters, and determining a sample space of the independent variable parameters based on a test design method;

calculating fluid mechanics calculation is carried out on each group of independent variable parameters in the sample space, so that test data of a centrifugal compressor simulation stage under each group of independent variable parameters are obtained;

Analyzing the test data to obtain a dimensionless value range of the independent variable parameter, and completing the design of the stator structure of the centrifugal compressor based on the dimensionless value range;

Wherein the argument parameters comprise a reflux disk side radius, a reflux inlet width, a reflux disk side inclination angle, a reflux cover side inclination angle, a reflux outlet disk side radius and a reflux to axis distance; the determining the independent variable parameter of the meridian line according to the meridian line of the curve and the reflux device comprises the following steps:

Dividing the meridian line into a straight line segment and a circular arc segment according to the geometric structure of the meridian line, wherein the straight line segment comprises a reflux disc side line, a reflux cover side line and a reflux outlet disc side line; the arc section comprises a reflux disc side curve molded line, a reflux cover side curve molded line, a reflux outlet disc side curve molded line and a reflux outlet cover side curve molded line;

Determining a dish-side radius of the reflux based on the dish-side curve line of the reflux;

Determining a reflux inlet width based on the reflux cover side curve line and the reflux disk side curve line;

Determining the reflux disc side inclination angle based on the reflux disc side profile being tangent to the reflux disc side curve profile;

determining the reflux cover side inclination angle based on the reflux cover side molded line being tangent to the reflux cover side curved line;

Determining the outlet disc side radius of the reflux based on the reflux outlet disc side curve profile being tangent to the reflux disc side profile and the reflux outlet disc side profile, respectively;

and determining the distance between the reflux device and the axle center based on the curve line of the reflux device outlet cover side.

2. The method of claim 1, wherein after said determining the independent parameters of the meridian line from the meridian lines of the curve and the reflux, the method further comprises:

calculating the intersection point coordinates of all section molded lines in the straight line section and the circle center coordinates of all section curved line molded lines in the circular arc section according to the geometric structure of the meridian molded lines;

Establishing a function equation based on the intersection point coordinates and the circle center coordinates, wherein the independent variable of the function equation is the independent variable parameter;

Equally dividing each section molded line in the straight line section and each section curved line in the circular arc section through interpolation operation to obtain coordinates of each interpolation point;

And integrating the coordinates of the interpolation points with the function equation to obtain the parameterized model of the meridian line.

3. The method of claim 1, wherein the trial design method is any one of a full-factor design method, an orthogonal design method, and a uniform design method.

4. The method of claim 3, wherein the obtaining a plurality of sets of the argument parameters, determining a sample space of the argument parameters based on a test design method, comprises:

And determining a sample space of the independent variable parameters in a plurality of groups of independent variable parameters based on a uniform dispersion principle by adopting an orthogonal design method, wherein the sample space comprises at least three groups of independent variable parameters.

5. The method of claim 4, wherein analyzing the test data to obtain a dimensionless range of values for the argument parameter comprises:

establishing a test scheme orthogonal table based on the test data;

Acquiring the variation trend of the variation of the independent variable parameter to the test data according to the test scheme orthogonal table, and drawing a trend graph;

and selecting part of the independent variable parameters according to the trend graph to carry out modeling and calculation, and determining the dimensionless value range of the independent variable parameters.

6. The method of claim 1, wherein the test data comprises aerodynamic performance of a centrifugal compressor model stage comprising polytropic efficiency of the centrifugal compressor and flow field information comprising uniformity of the reflux outlet flow field.

7. The method of claim 1, wherein the parameters of the meridian line include a diffuser outlet width, and the dimensionless range of values includes a ratio of a diffuser disk side radius to the diffuser outlet width, a ratio of a diffuser inlet width to the diffuser outlet width, a ratio of a diffuser outlet disk side radius to the diffuser outlet width, a ratio of a diffuser to an axial center spacing to the diffuser outlet width, a diffuser disk side tilt angle, and a diffuser cover side tilt angle.

8. The method of claim 7, wherein the completing the design of the centrifugal compressor stator structure based on the dimensionless range of values comprises:

Selecting the numerical value of the dimensionless parameter in the dimensionless value range;

Obtaining the value of the independent variable parameter based on the value of the dimensionless number;

and determining meridian lines of the curve and the reflux device according to the numerical value of the independent variable parameter, and completing the design of the stator structure of the centrifugal compressor.

9. The method of claim 1, wherein after the designing of the centrifugal compressor stator structure based on the dimensionless range of values is completed, the method further comprises:

And performing computational fluid dynamics calculation on the whole pneumatic model of the centrifugal compressor, and performing test verification to obtain test data.