A multi-row blade deformation method and device based on geometry and network linkage

Abstract

The present application provides a method and device for deformation of multiple rows of blades based on geometry and network linkage, which belongs to the field of aerospace technology. The method provided by the present application includes: establishing a multi-row blade mesh model to obtain a mesh to be deformed; determining mesh deformation control points based on the geometric properties of the mesh to be deformed, wherein the geometric properties at least include mesh block properties and boundary properties of each mesh block; controlling the deformation of the multi-row blade mesh model based on the mesh deformation control points and the RBF deformation method; wherein the radial basis function and the influence radius are calculated based on the distance relationship of each point in the mesh, and the points within the influence radius are deformed based on the radial basis function update to achieve the deformation of the entire multi-row blade mesh model. The method and device for deformation of multiple rows of blades based on geometry and network linkage provided by the present application can increase the efficiency of blade deformation.

Description

Technical Field

[0001] The present application relates to the field of aerospace technology, and in particular to a method and device for deforming multiple rows of blades based on geometry and network linkage. Background Art

[0002] The full three-dimensional aerodynamic optimization of axial compressors has the characteristics of high optimization variable dimension and expensive evaluation. For high-dimensional problems, geometric parameterization methods such as FFD (Free-Form Deformation), DFFD (Direct Free-Form Deformation), and RBF (Radial Basis Function) are generally used to reduce the dimension; for problems with expensive evaluation, neural networks, proxy models, etc. are generally used to replace the results of real evaluation to reduce the number of evaluations and reduce the total optimization time. Real evaluation refers to full three-dimensional CFD (Computational Fluid Dynamics) aerodynamic analysis, which mainly includes grid generation, flow field calculation, and result processing. Among them, grid generation and flow field iterative calculation are the most time-consuming. In full three-dimensional CFD aerodynamic optimization, geometric parameterization methods are generally used for blade and flow channel geometric deformation, and the calculation grid is regenerated after the deformation is completed. For each real calculation, a grid generation calculation is required. As the number of blade rows increases, the area that needs to be controlled by the geometric parameterization method increases, the number of control bodies corresponding to the FFD and DFFD methods increases, and the calculation time increases sharply, making the geometric parameterization method itself a time-consuming operation. At the same time, each row of grids needs to be generated in sequence by a single core, and the time consumption also increases significantly. Therefore, how to improve the efficiency of axial flow compressor blade deformation is an urgent problem to be solved. At present, the flow field grid deformation is usually directly operated by RBF, but this method is mostly used in the refined small deformation of the outflow or single-row blades. In the direction of grid deformation of multi-row blades and multi-stage axial flow compressors, research is still blank. Summary of the invention

[0003] In view of this, the present application provides a multi-row blade deformation method and device based on geometry and network linkage, which can increase the efficiency of blade deformation.

[0004] Specifically, the present application is implemented through the following technical solutions:

[0005] In a first aspect, the present application provides a multi-row blade deformation method based on geometry and network linkage, the method comprising:

[0006] Establish a mesh model of multiple rows of blades to obtain the mesh to be deformed;

[0007] Determining mesh deformation control points based on geometric properties of the mesh to be deformed, wherein the geometric properties at least include mesh block properties and boundary properties of each mesh block;

[0008] Controlling the deformation of the multi-row blade mesh model based on the mesh deformation control points and the RBF deformation method;

[0009] The radial basis function and the influence radius are calculated based on the distance relationship between each point in the grid, and the points within the influence radius are deformed based on the radial basis function update to achieve the deformation of the entire multi-row blade grid model.

[0010] A second aspect of the present application provides a multi-row blade deformation device based on geometry and network linkage, the device comprising an establishment module, a determination module and a control module; wherein;

[0011] The building module is used to build a grid model of multiple rows of blades to obtain the grid to be deformed;

[0012] The determination module is used to determine the mesh deformation control points based on the geometric properties of the mesh to be deformed, wherein the geometric properties at least include mesh block properties and boundary properties of each mesh block;

[0013] The control module is used to control the deformation of the multi-row blade grid model based on the grid deformation control points and the RBF deformation method;

[0014] The radial basis function and the influence radius are calculated based on the distance relationship between each point in the grid, and the points within the influence radius are deformed based on the radial basis function update to achieve the deformation of the entire multi-row blade grid model.

[0015] The present application provides a method and device for deformation of multiple rows of blades based on geometric and network linkage. By establishing a grid model of multiple rows of blades and analyzing the grid blocks and boundary attributes according to their geometric properties, the shape and structure of the blades can be accurately understood and controlled. In addition, the deformation method based on radial basis functions can flexibly adjust and deform the grid model without regenerating the entire grid, which can increase the efficiency of blade deformation. Specifically, the present invention converts the deformation of the three-dimensional model into the deformation of the boundary contour line based on the grid model of multiple rows of blades, starting from the distribution shape of the boundary, and simplifies the calculation process of body deformation. During deformation, the shape of the blade must be smooth. Therefore, compared with the calculation method of each point, the present invention first fits the shape of the curve into the form of a basis function, based on the control of a small number of control points and the adjustment of the influence radius, a smooth curve deformation without convex changes is formed, and a smooth deformed curve is directly obtained in one step, without calculating the deformation position of each point, which greatly reduces the deformation calculation amount. At the same time, the deformed blade shape does not need to be smoothed, directly meets the shape requirements and deformation requirements, simplifies the deformation steps, and improves the shape design efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 A flowchart of Embodiment 1 of the multi-row blade deformation method based on geometry and network linkage provided in this application;

[0017] Figure 2 A schematic diagram of the flow field boundary grid layer vertices and blade deformation control points shown in an exemplary embodiment of the present application;

[0018] Figure 3 A three-dimensional blade deformation comparison diagram showing an exemplary embodiment of the present application;

[0019] Figure 4 A schematic diagram showing a comparison of blade deformation results of a Gaussian basis function and a biharmonic spline basis function at different influence radii shown in an exemplary embodiment of the present application;

[0020] Figure 5 This is a structural schematic diagram of Example 1 of a multi-row blade deformation device based on geometry and network linkage provided in this application. DETAILED DESCRIPTION

[0021] Here, exemplary embodiments are described in detail, and examples thereof are shown in the accompanying drawings. When the following description refers to the drawings, unless otherwise indicated, the same numbers in different drawings represent the same or similar elements. The implementations described in the following exemplary embodiments do not represent all implementations consistent with the present application.

[0022] The terms used in this application are only for the purpose of describing specific embodiments and are not intended to limit this application. The singular forms of "a", "said" and "the" used in this application are also intended to include plural forms, unless the context clearly indicates other meanings. It should also be understood that the term "and / or" used in this article refers to and includes any or all possible combinations of one or more associated listed items.

[0023] It should be understood that although the terms first, second, third, etc. may be used in the present application to describe various information, these information should not be limited to these terms. These terms are only used to distinguish the same type of information from each other. For example, without departing from the scope of the present application, the first information may also be referred to as the second information, and similarly, the second information may also be referred to as the first information. Depending on the context, the word "if" as used herein may be interpreted as "at the time of" or "when" or "in response to determining".

[0024] Figure 1 This is a flow chart of the first embodiment of the multi-row blade deformation method based on geometry and network linkage provided by this application. Please refer to Figure 1 , the method provided in this embodiment may include:

[0025] S101, establishing a mesh model of multiple rows of blades to obtain meshes to be deformed.

[0026] It should be noted that the full three-dimensional flow field analysis methods of axial compressors are mainly divided into two categories. One is the grid-based method, which solves the control equations by dividing the grid in the flow field area, advancing in time and space, and combining turbulence models. The second is the gridless method represented by the Lattice-Boltzmann (LBM) method. Currently, mainstream commercial software (such as ANSYS, STAR-CCM+, NUMECA) and open source projects (OPENFOAM) all use grid-based methods, and the grid and flow field information are stored in the CGNS file format.

[0027] Among them, CGNS (CFD General Notation System) is a standard file format for storing and exchanging CFD data, jointly developed by NASA, Boeing, Lockheed Martin, US AirForce and other institutions. It can be used to store geometric meshes, physical models, numerical results and other information in CFD calculations, and supports a variety of CFD solvers and post-processing software (CFview, Tecplot, etc.). CGNS files use a structured binary storage method to improve data reading and writing efficiency, and a hierarchical storage method is conducive to data stratification and management.

[0028] Specifically, a CGNS file consists of two main parts: a file header and a data area. The file header contains metadata and structural information of the file, such as the CGNS version number, file description, mesh type, physical model, etc. The file header consists of structured text and can be read and written through a text editor or the corresponding functions in the CGNS library. The data area contains actual data, such as mesh coordinates, mesh topology, boundary conditions, flow field data, etc. The data area is a hierarchical structure consisting of multiple nodes and links, and each node can contain one or more data items. The main structure of the data area of ​​a CGNS file is shown in Table 1:

[0029] Table 1 Basic structure of CGNS files

[0030]

[0031] Commercial CFD calculation software has the function of reading CGNS files. Some post-processing software such as Tecplot can read and export the grid point position and flow field information of CGNS files, but it cannot directly write the deformed geometry back to CGNS. CGNS officially open-sources the interface for reading and modifying CGNS files. pycgns is a Python extension library for reading and writing CGNS files. It is developed based on the CGNS C language library and provides a series of Python interface functions that can easily read and modify the data in CGNS files. The introduction of the main modules of Pycgns is shown in Table 2:

[0032] Table 2 Introduction to the main modules of Pycgns

[0033]

[0034] It should be noted that the CFD calculation tool for aerodynamic optimization in this embodiment uses the commercial software NUMECA, in which the Autogrid5 module is an automatic grid generation tool that generates grid information and stores it in a CGNS file.

[0035] Combined with the above description, establishing a multi-row blade mesh model and obtaining the mesh to be deformed includes: generating mesh information based on aerodynamic optimization CFD calculation tools to establish a multi-row blade mesh model; reading the CGNS file of the multi-row blade mesh model; obtaining the mesh to be deformed based on the point information of each point in the read mesh block; wherein the information of each point includes the coordinate information of the point in the X, Y, and Z directions. Specifically, the data of the mesh nodes of each data block can be read through the getValueByPath function, including CoordinatesX (X-direction coordinates), CoordinatesY (Y-direction coordinates), and CoordinatesZ (Z-direction coordinates), to obtain all the mesh points in the calculation domain and perform direct deformation of the flow field mesh.

[0036] It should be noted that after reading the CGNS file to obtain the mesh nodes, since the RBF deformation will not change the mesh topology and the mesh block information preset by NUMECA, in order to ensure the quality of the mesh and the continuity between the topology and mesh blocks, all mesh points need to be introduced into the RBF deformation control.

[0037] In the specific implementation, when reading the CGNS file, the pycgns library function is used to obtain the position of each grid point, the grid block array structure, the CGNS file tree and the position of the grid node through the grid block name index. After obtaining the coordinates of all grid points, each grid block is flattened and combined. Since RBF solves each grid point in the deformation area independently, the grid points can be imported in any order to form the overall flow field grid.

[0038] As an optional embodiment, unlike the traditional single blade, the present invention provides a grid model of multiple blades. When a single row of blades is deformed, there is no need to consider the deformation of the interface between rows. When multiple rows of blades are deformed, each row of blades deforms independently, resulting in the points at the interface between rows not corresponding to each other, which leads to the inability to calculate or large calculation errors. Therefore, in order to ensure the accuracy of the calculation results, the deformation at the interface needs to be considered, which will cause complex force transfer relationships between the blades and the modeling process is relatively complicated. The present invention mainly deforms each blade and only focuses on the deformation characteristics of the blades. The solution provided by the present invention converts the deformation of the three-dimensional structure into the deformation of the boundary curve. Therefore, for the modeling of multiple blades, only the deformation of the contour boundary needs to be paid attention to, and the force analysis inside the three-dimensional structure can be ignored, which greatly reduces the difficulty of modeling. Specifically, the establishment of a mesh model of multiple rows of blades to obtain a mesh to be deformed includes: establishing a first mesh model of each single row of blades in the multiple rows of blades; determining the connection parts and deformation properties of the connection parts of each first mesh model based on the force analysis of the connection parts of the multiple rows of blades; splicing each first mesh model based on the connection parts and the deformation properties to obtain the mesh to be deformed. On this basis, the determination of mesh deformation control points based on the geometric properties of the mesh to be deformed includes: determining the mesh deformation control points of a single blade based on the geometric shapes of each blade in the multiple rows of blades; determining the connection deformation control points based on the deformation degree of the connection parts; determining the blade boundary deformation control points based on the deformation degree of the connection parts in a single blade; and obtaining the mesh deformation control points by combining the mesh deformation control points of a single blade, the connection deformation control points, and the blade boundary deformation control points.

[0039] S102: Determine mesh deformation control points based on geometric properties of the mesh to be deformed, wherein the geometric properties at least include mesh block properties and boundary properties of each mesh block.

[0040] It should be noted that determining the mesh deformation control points based on the geometric properties of the mesh to be deformed includes: locating the blade wall mesh from the mesh to be deformed; locating multiple first deformation control points on the blade wall mesh; dividing the mesh to be deformed into blocks, identifying the boundaries of each mesh block, and locating multiple second deformation control points on the boundaries; combining the first deformation control points and the second deformation control points as network deformation control points, wherein the first deformation control points are used to control the deformation of the multi-row blade mesh model, and the second deformation control points are used to ensure that the smoothness of the multi-row blade mesh model after deformation is greater than a preset threshold. Specifically, in order to make the blade geometric deformation intuitive and effective and to ensure the accuracy of the CFD calculation of the flow field mesh after deformation, it is necessary to select deformation control points in the innermost layer of the blade mesh (blade wall mesh) and the boundary layer of each mesh block. The deformation control points (first deformation control points) on the blade are used to directly control the mesh deformation, and the boundary deformation control points (second deformation control points) on the boundary mesh layer are used to ensure the overall flow field mesh structure. Figure 2 This is a schematic diagram of the flow field boundary grid layer vertices and blade deformation control points shown in an exemplary embodiment of the present application. Please also refer to Figure 2 In Figures A and B, when performing RBF parametric deformation, the deformation control points at the vertices are kept fixed to limit the frame deformation of the flow field grid. The deformation control points on the blades are moved to perform parametric deformation of the blades. The final three-dimensional blade deformation comparison diagram is shown in Figure 1. Figure 3 shown.

[0041] It should be noted that the selection of deformation control points in the prior art may rely more on simple geometric features or manual selection. The method provided in this application can more intelligently and efficiently automatically locate deformation control points under complex geometric shapes by combining grid block attributes and boundary attributes, ensuring that the deformation requirements of grids in different regions can be met more finely. In addition, the first deformation control point directly acts on the blade wall to achieve precise control of the geometric deformation of the blade; the second deformation control point ensures the smoothness of the boundary grid layer and balances the continuity of local details and overall deformation.

[0042] It should also be noted that the first deformation control point is used to directly control the geometric shape of the blade, so it can be determined based on the position of the blade wall grid (first, the wall area of ​​the blade must be located from the grid to be deformed), and is usually distributed at key positions of the blade, such as the leading edge, trailing edge, and the convex and concave parts of the airfoil; the second deformation control point is used to maintain the overall smoothness and structural continuity of the grid during the deformation process, so it can be determined based on the boundary properties of the grid block, especially the boundary layer of the grid block (generally located on the boundary grid layer, especially the vertices of the flow field boundary grid layer, and usually set in the area adjacent to the blade wall). Among them, when the first deformation control point is deformed by radial basis function, the position will be adjusted to reflect the required geometric deformation of the blade. Specifically, the movement of the first deformation control point will cause the position of the adjacent grid nodes to change accordingly, thereby realizing the overall deformation of the blade; when the second deformation control point is deformed by radial basis function, these deformation control points often remain stationary as fixed reference points, thereby limiting excessive deformation of the grid in the flow field framework.

[0043] S103, controlling the deformation of the grid model of the multiple rows of blades based on the grid deformation control points and the RBF deformation method.

[0044] The radial basis function and the influence radius are calculated based on the distance relationship between each point in the grid, and the points within the influence radius are deformed based on the radial basis function update to achieve the deformation of the entire multi-row blade grid model.

[0045] It should be noted that the method for determining the radial basis function and the influence radius includes: determining the type of radial basis function according to the mutation degree of each radial basis function after deformation, the degree of change within the influence radius, and the smoothness requirement of the mesh to be deformed; calculating the distance between each point in the mesh to be deformed and the mesh deformation control point; and determining the influence radius according to the distance and the type of radial basis function. Among them, the radial basis function type is determined according to the mutation degree of each radial basis function after deformation because some radial basis functions may change dramatically within a short distance, while other functions may be smoother; the radial basis function type is determined according to the degree of change within the influence radius after deformation because different radial basis functions change differently within the influence radius, affecting the sensitivity of the mesh point to the change of the deformation control point; the radial basis function type is determined according to the smoothness of the mesh to be deformed after deformation by each radial basis function because it is necessary to select a suitable function according to the specific application to ensure the smoothness and quality of the mesh after deformation.

[0046] Specifically, the radial basis function type determined based on the above three conditions is the radial basis function type that best balances local accuracy and global smoothness, and can meet specific design and optimization requirements. In specific implementation, in the mesh to be deformed, for each grid point, the Euclidean distance or other appropriate distance measure between it and the deformation control point is calculated, and then the influence radius is determined based on the distance and the radial basis function type. Among them, the influence radius refers to the effective range of deformation of the grid points in the surrounding area by the deformation control point, and the points within this range will be affected by the deformation of the control point. The selection of the influence radius is usually based on the coverage area and smoothness, among which the coverage area is used to ensure that the influence radius can cover all important grid points around the deformation control point, and the smoothness is used to avoid excessive smoothing due to too large a radius, or local discontinuity due to too small a radius during selection.

[0047] It should also be noted that the selection of radial basis function and influence radius has a great influence on the deformation results. Commonly used radial basis functions include Gaussian spline and multi quadraticbiharmonic spline. Figure 4 This is a schematic diagram showing the comparison of blade deformation results of Gaussian basis function and biharmonic spline basis function under different influence radii in an exemplary embodiment of the present application. Figure 4 ,Depend on Figure 4 It can be seen that the Gaussian basis function has a stronger local deformation. When the influence radius is small, there is deformation only near the blade deformation control point, and it decays quickly with distance. When the influence radius R=1, the influence range is significantly increased, but the center of its deformation control point still has a large deformation gradient. There are major problems with the smoothness of the deformed grid, which in turn affects the accuracy of the flow field solution. The biharmonic spline basis function has a relatively gentle deformation, a large influence range, and a slow deformation decay with distance. While ensuring local deformation, it can take into account the overall deformation of the blade. The local smoothness of the grid is better. When R=1, the deformation of two adjacent control points is superimposed, which may cause the grid deformation to exceed the set value, resulting in a decrease in grid quality and affecting the flow field solution. Therefore, in this embodiment, the biharmonic spline basis function is preferably used, and the influence radius is set to 0.1.

[0048] In a specific implementation, the radial basis function-based update, before deforming the points within the influence radius, also includes: calculating the distance between each point in the mesh to be deformed and the mesh deformation control point, and determining the influence radius according to the distance; determining the radial basis function type according to the influence radius; based on the radial basis function type, representing the position of each point in the mesh to be deformed as a linear combination of the radial basis functions of the mesh deformation control point positions; calculating the radial basis function coefficients based on the linear combination of the radial basis functions and the mesh deformation control point positions before and after deformation, and completing the radial basis function update based on the radial basis function coefficients to complete the deformation. It should be noted that the above distance is the Euclidean distance, where the Euclidean distance is the most common distance measurement method, which is used to calculate the straight-line distance between two points. For example, in one embodiment, suppose the set of mesh points to be deformed is {p j}(j=1,2,3…,M), the set of mesh deformation control points is {x i} (i=1,2,3…,N), then the Euclidean distance calculation formula is:

[0049] ;

[0050] Among them, r ij is the mesh point p to be deformed j With deformation control point x i The Euclidean distance between j is the coordinate of the grid point to be deformed, x i are the coordinates of the deformation control points, Represents Euclidean distance calculation.

[0051] After obtaining the distance between each point in the mesh to be deformed and the mesh deformation control point, the influence radius can be determined based on relevant formulas and other methods. For details, please refer to the introduction of relevant technologies, which will not be repeated here.

[0052] It should be noted that after controlling the deformation of the multi-row blade mesh model, it also includes: reading the multi-row blade mesh model, dividing the mesh in the multi-row blade mesh model into blocks according to the geometric properties of the multi-row blade mesh model; establishing a tree diagram between each block according to the positional relationship of each block in the multi-row blade mesh model; establishing a file tree of model files corresponding to each block based on the tree diagram; modifying the deformed mesh blocks in the file tree, reconstructing the multi-row blade mesh model based on the modified file tree, and completing the overall flow field mesh deformation. This ensures that the overall mesh structure and geometric characteristics are maintained or re-established while performing local mesh deformation.

[0053] Optionally, the process of completing the overall flow field mesh deformation includes: selecting the vertices of each mesh block after block division as fixed control points; determining the blade control points according to the movement requirements and the shape of the multi-row blade model, and the blade control points are used to limit the movement in at least two directions; the fixed control points remain unchanged, and the blade control points are moved based on the RBF method to complete the overall flow field mesh deformation. It should be noted that these fixed control points remain unchanged throughout the deformation process to maintain the basic structure and continuity of the mesh. In addition, according to the shape and movement requirements of the blade, additional blade control points are determined, which are usually located at the key parts of the blade to limit the movement of the blade in two directions. For example, the leading edge, trailing edge or other key points of the blade can be selected as control points to ensure that the shape and position of the blade meet the design requirements. It should be noted that the fixed control points remain unchanged, while the blade control points are moved using the radial basis function method according to the movement requirements and shape changes, and the movement of the blade control points is to locally adjust the mesh to meet the blade shape and movement requirements.

[0054] The method provided in this embodiment is to establish a grid model of multiple rows of blades, obtain the grid to be deformed, and then determine the grid deformation control points based on the geometric properties of the grid to be deformed, wherein the geometric properties at least include the grid block properties and the boundary properties of each grid block, and finally control the deformation of the grid model of multiple rows of blades based on the grid deformation control points and the RBF deformation method; wherein the radial basis function and the influence radius are calculated based on the distance relationship of each point in the grid, and the points within the influence radius are deformed based on the radial basis function update to achieve the deformation of the entire grid model of multiple rows of blades. In this way, by establishing a grid model of multiple rows of blades and analyzing the grid block and boundary properties according to its geometric properties, the shape and structure of the blades can be accurately understood and controlled. In addition, using the deformation method based on the radial basis function, the grid model can be flexibly adjusted and deformed without regenerating the entire grid, which can increase the efficiency of blade deformation. Specifically, the present invention converts the deformation of the three-dimensional model into the deformation of the boundary contour line based on the grid model of multiple rows of blades, starting from the distribution shape of the boundary, and simplifies the calculation process of body deformation. During deformation, the blade's shape must be smooth. Therefore, compared with the method of calculating each point, the present invention first fits the shape of the curve into the form of a basis function, and forms a smooth curve deformation without convex changes based on the control of a small number of control points and the adjustment of the influence radius. A smooth deformed curve is obtained directly in one step without calculating the deformation position of each point, which greatly reduces the amount of deformation calculation. At the same time, the deformed blade shape does not need to be smoothed, and the shape requirements and deformation requirements are directly met, which simplifies the deformation steps and improves the efficiency of shape design.

[0055] Corresponding to the aforementioned embodiment of a multi-row blade deformation method based on geometry and network linkage, the present application also provides an embodiment of a multi-row blade deformation device based on geometry and network linkage.

[0056] Figure 5 This is a structural diagram of the first embodiment of the multi-row blade deformation device based on geometry and network linkage provided by this application. Figure 5 , the device provided in this embodiment includes an establishing module 510, a determining module 520 and a controlling module 530; wherein;

[0057] The building module 510 is used to build a mesh model of multiple rows of blades to obtain meshes to be deformed;

[0058] The determination module 520 is used to determine the mesh deformation control points based on the geometric properties of the mesh to be deformed, wherein the geometric properties at least include mesh block properties and boundary properties of each mesh block;

[0059] The control module 530 is used to control the deformation of the multi-row blade grid model based on the grid deformation control points and the RBF deformation method;

[0060] The radial basis function and the influence radius are calculated based on the distance relationship between each point in the grid, and the points within the influence radius are deformed based on the radial basis function update to achieve the deformation of the entire multi-row blade grid model.

[0061] The device of this embodiment can be used to perform Figure 1 The steps, specific implementation principles and implementation processes of the method embodiment shown are similar and will not be repeated here.

[0062] The implementation process of the functions and effects of each unit in the above-mentioned device is specifically described in the implementation process of the corresponding steps in the above-mentioned method, and will not be repeated here.

[0063] For the device embodiment, since it basically corresponds to the method embodiment, the relevant parts can refer to the partial description of the method embodiment. The device embodiment described above is only schematic, wherein the units described as separate components may or may not be physically separated, and the components displayed as units may or may not be physical units, that is, they may be located in one place, or they may be distributed on multiple network units. Some or all of the modules may be selected according to actual needs to achieve the purpose of the present application scheme. A person of ordinary skill in the art can understand and implement it without paying any creative work.

[0064] The above description is only a preferred embodiment of the present application and is not intended to limit the present application. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present application shall be included in the scope of protection of the present application.

Claims

1. A multi-row blade deformation method based on geometry and network linkage, characterized in that: The method comprises: Establish a mesh model of multiple rows of blades to obtain the mesh to be deformed; Determining mesh deformation control points based on geometric properties of the mesh to be deformed, wherein the geometric properties at least include mesh block properties and boundary properties of each mesh block; Controlling the deformation of the multi-row blade mesh model based on the mesh deformation control points and the RBF deformation method; The radial basis function and the influence radius are calculated based on the distance relationship between each point in the grid, and the points within the influence radius are deformed based on the radial basis function update to achieve the deformation of the entire multi-row blade grid model; The step of determining the mesh deformation control points based on the geometric properties of the mesh to be deformed comprises: Locating a blade wall mesh from the mesh to be deformed; Positioning a plurality of first deformation control points on the blade wall grid; Dividing the to-be-deformed mesh into blocks, identifying boundaries of each mesh block, and locating a plurality of second deformation control points on the boundaries; Combining the first deformation control point and the second deformation control point as a network deformation control point, wherein the first deformation control point is used to control the deformation of the multi-row blade mesh model, and the second deformation control point is used to ensure that the smoothness of the multi-row blade mesh model after deformation is greater than a preset threshold; The step of establishing a mesh model of multiple rows of blades to obtain a mesh to be deformed includes: Establishing a first meshed model of each single-row blade in the plurality of rows of blades; Determining the connection parts and deformation properties of the connection parts of each of the first meshed models according to the force analysis of the connection parts of the multiple rows of blades; The first meshed models are spliced ​​based on the connection parts and the deformation properties to obtain the mesh to be deformed.

2. The method according to claim 1, characterized in that: The method for determining the radial basis function and the influence radius comprises: Determine the type of radial basis function according to the mutation degree after deformation of each radial basis function, the degree of change within the influence radius, and the smoothness requirement of the mesh to be deformed; Calculating the distance between each point in the to-be-deformed mesh and the mesh deformation control point; The influence radius is determined according to the distance and the radial basis function type.

3. The method according to claim 1, characterized in that: Before the points within the influence radius are deformed based on the radial basis function update, the method further includes: Calculating the distance between each point in the to-be-deformed mesh and the mesh deformation control point, and determining the influence radius according to the distance; Determining a radial basis function type according to the influence radius; Based on the radial basis function type, the position of each point in the to-be-deformed mesh is represented as a linear combination of the radial basis functions of the mesh deformation control point positions; The radial basis function coefficients are calculated based on the linear combination of the radial basis functions and the positions of the mesh deformation control points before and after the deformation, and the radial basis function is updated according to the radial basis function coefficients to complete the deformation.

4. The method according to claim 1, characterized in that After controlling the deformation of the multi-row blade mesh model, the method further includes: Reading the multi-row blade grid model, and dividing the grids in the multi-row blade grid model into blocks according to the geometric properties of the multi-row blade grid model; Establishing a tree diagram between each block according to the positional relationship of each block in the multi-row blade grid model; Based on the tree diagram, a file tree of model files corresponding to each block is established; The deformed grid blocks in the file tree are modified, and the multi-row blade grid model is reconstructed based on the modified file tree to complete the overall flow field grid deformation.

5. The method according to claim 4, characterized in that The process of completing the overall flow field grid deformation includes: Select the vertices of each grid block after segmentation as fixed control points; Determining blade control points according to movement requirements and the shape of the multi-row blade model, wherein the blade control points are used to restrict movement in at least two directions; The fixed control points remain unchanged, and the blade control points are moved based on the RBF deformation method to complete the overall flow field grid deformation.

6. The method according to claim 1, characterized in that The step of determining the mesh deformation control points based on the geometric properties of the mesh to be deformed comprises: Determining a mesh deformation control point of a single blade according to the geometric shapes of each blade in the plurality of rows of blades; Determining a deformation control point at the connection according to the degree of deformation of the connection part; Determining a blade boundary deformation control point according to a degree of deformation of a single blade at a location connected to the connection portion; The mesh deformation control points of a single blade, the deformation control points of the connection and the deformation control points of the blade boundary are integrated to obtain the mesh deformation control points.

7. The method according to claim 1, characterized in that The step of establishing a mesh model of multiple rows of blades and obtaining a mesh to be deformed comprises: Generate mesh information based on aerodynamic optimization CFD calculation tools and establish a mesh model of multiple rows of blades; Reading the CGNS file of the multi-row blade mesh model; The mesh to be deformed is obtained based on the information of each point in the read mesh block; wherein the information of each point includes the coordinate information of the point in the X, Y, and Z directions.

8. A multi-row blade deformation device based on geometry and network linkage, characterized in that: The device comprises an establishing module, a determining module and a controlling module; wherein, The building module is used to build a grid model of multiple rows of blades to obtain the grid to be deformed; The determination module is used to determine the mesh deformation control points based on the geometric properties of the mesh to be deformed, wherein the geometric properties at least include mesh block properties and boundary properties of each mesh block; The control module is used to control the deformation of the multi-row blade grid model based on the grid deformation control points and the RBF deformation method; The radial basis function and the influence radius are calculated based on the distance relationship between each point in the grid, and the points within the influence radius are deformed based on the radial basis function update to achieve the deformation of the entire multi-row blade grid model; The step of determining the mesh deformation control points based on the geometric properties of the mesh to be deformed comprises: Locating a blade wall mesh from the mesh to be deformed; Positioning a plurality of first deformation control points on the blade wall grid; Dividing the to-be-deformed mesh into blocks, identifying boundaries of each mesh block, and locating a plurality of second deformation control points on the boundaries; Combining the first deformation control point and the second deformation control point as a network deformation control point, wherein the first deformation control point is used to control the deformation of the multi-row blade mesh model, and the second deformation control point is used to ensure that the smoothness of the multi-row blade mesh model after deformation is greater than a preset threshold; The step of establishing a mesh model of multiple rows of blades to obtain a mesh to be deformed includes: Establishing a first meshed model of each single-row blade in the plurality of rows of blades; Determining the connection parts and deformation properties of the connection parts of each of the first meshed models according to the force analysis of the connection parts of the multiple rows of blades; The first meshed models are spliced ​​based on the connection parts and the deformation properties to obtain the mesh to be deformed.

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