A method, apparatus, device, and storage medium for generating curved quadrilateral dominant meshes for aircraft.

Abstract

This application discloses a method, apparatus, device, and storage medium for generating a curved quadrilateral dominant mesh for an aircraft, relating to the field of computational fluid dynamics. The method includes: creating a surface unstructured mesh based on surface mesh generation parameters from the aircraft's CAD file, conformally mapping it to the parameter domain plane, and calculating the vertex compression ratio of each mesh vertex; selecting the current starting point with the smallest compression ratio and the largest vertex to be compared in the adjacency list, determining the current vertex to be processed with the smallest compression ratio among adjacent vertices and its propulsion direction; determining the current discrete points to be processed based on the current compression ratio and coordinate information, generating the current contour lines; if the current compression ratio does not exceed a threshold, iteratively updating the current starting point and jumping back to the step of determining the current vertex to be processed; projecting the discrete points onto the outer contour lines in contour line order, and generating a curved quadrilateral dominant mesh based on the distance ratio between each discrete point and the projected point, thereby improving the generation efficiency of the curved quadrilateral mesh.

Description

Technical Field

[0001] This invention relates to the field of computational fluid dynamics, and in particular to a method, apparatus, device, and storage medium for generating a curved quadrilateral dominant mesh for an aircraft. Background Technology

[0002] Currently, quadrilateral dominant meshes have significant advantages in engineering simulation, geometric modeling, and parameterization. With the same number of elements, quadrilateral elements have higher interpolation accuracy and convergence than triangular elements. The essential geometric constraints of quadrilateral dominant mesh generation and the balance between topological rules and computational efficiency are challenges. It is necessary to satisfy the global constraints of differential geometry, singular point exponents, compatibility with noisy meshes and multiple boundary conditions, and control post-processing overhead.

[0003] Existing methods for generating quadrilateral dominant meshes include the classic Q-Morph front advance method, which advances quadrilateral elements from the boundary inward, merging triangular meshes into quadrilateral meshes and avoiding residual triangles through active front management; the domain decomposition method, which recursively divides complex domains into simple subdomains and generates subdomain meshes using predefined templates; and the frame field method, which defines mesh edge directions through a frame field and generates topological partitions by combining curvature constraints, advancing quadrilateral meshes within the partitions and filling a small number of triangles. However, these methods still suffer from problems such as input quality dependence, extreme geometric adaptability, and 3D expansion.

[0004] However, the aforementioned existing technologies struggle to balance mathematical constraints and feature preservation, singularity distribution optimization still relies on manual experience, and large-scale models suffer from high computational complexity, significantly reducing mesh generation efficiency. Complex meshes are prone to geometric cracks, requiring post-processing and introducing certain problems.

[0005] As can be seen from the above, improving the efficiency of generating quadrilateral-dominant meshes in the process of generating quadrilateral-dominant meshes for aircraft is an urgent problem to be solved. Summary of the Invention

[0006] In view of this, the purpose of this invention is to provide a method, apparatus, device, and storage medium for generating curved quadrilateral dominant meshes for aircraft, which can improve the efficiency of generating curved quadrilateral dominant meshes during the process of generating curved quadrilateral dominant meshes for aircraft, thereby enhancing the user experience. The specific solution is as follows:

[0007] In a first aspect, this application provides a method for generating a curved quadrilateral-dominant mesh for an aircraft, including:

[0008] Based on the CAD file of the aircraft, surface mesh generation parameters are determined, and an unstructured surface mesh is generated based on the surface mesh generation parameters. Then, the unstructured surface mesh is conformally mapped to a preset parameter domain space to obtain a parameter domain plane. The mesh edge metric corresponding to each mesh vertex in the parameter domain plane is determined, and the vertex compression rate is determined based on each mesh edge metric.

[0009] Based on the compression ratio of each vertex, an adjacency list is determined. Then, the current starting point with the smallest vertex compression ratio and the vertex to be compared with the largest vertex compression ratio in the adjacency list are determined. The current vertex to be processed with the smallest compression ratio among the vertices adjacent to the current starting point in the adjacency list is determined. Then, the current direction of advancement is determined based on the current starting point and the current vertex to be processed.

[0010] Based on the current compression ratio and current coordinate information of the current vertex to be processed, determine each discrete point to be processed with the same compression ratio as the current compression ratio in the parameter domain plane, and determine the current contour line based on each discrete point to be processed and the current advancement direction. Then, determine whether the current compression ratio is greater than the compression ratio threshold corresponding to the vertex to be compared. If it is not greater, set the current vertex to be processed as the current starting point, and jump back to the step of determining the current vertex to be processed until the current compression ratio is greater than the compression ratio threshold.

[0011] According to the order in which the contour lines are generated, each discrete point on each contour line is vertically projected onto the adjacent outer contour line to obtain the projection point. Then, based on the distance ratio between each discrete point and the corresponding projection point, a mesh is generated to obtain the curved quadrilateral dominant mesh corresponding to the aircraft.

[0012] Optionally, the step of determining surface mesh generation parameters based on the CAD file of the aircraft, generating an unstructured surface mesh based on the surface mesh generation parameters, then conformally mapping the unstructured surface mesh to a preset parameter domain space to obtain a parameter domain plane, and determining the mesh edge metric corresponding to each mesh vertex in the parameter domain plane based on the unstructured surface mesh, and determining the vertex compression ratio based on each mesh edge metric, includes:

[0013] The CAD file of the aircraft is read, and surface mesh generation parameters including preset global target size and preset curvature adaptive angle are determined based on the CAD file. Then, a preset mesh generation algorithm is used to construct a surface unstructured mesh corresponding to the aircraft based on the surface mesh generation parameters.

[0014] The unstructured surface mesh is conformally mapped to a preset parameter domain space to obtain a parameter domain plane, and the mesh edge metric corresponding to each mesh vertex in the parameter domain plane is determined.

[0015] The discrete Ricci flow algorithm is used to map each grid vertex and associated edge in the unstructured surface mesh to a preset parameter domain space to obtain a parameter domain plane; the preset parameter domain space is a two-dimensional space; the parameter domain plane is a two-dimensional plane.

[0016] Determine the first mesh edge metric corresponding to each mesh vertex in the unstructured surface mesh and the second mesh edge metric corresponding to each mesh vertex in the parameter domain plane, so as to determine the corresponding vertex compression ratio based on the first mesh edge metric and the corresponding second mesh edge metric.

[0017] Optionally, the step of determining an adjacency list based on the compression ratio of each vertex, then determining the current starting point with the smallest compression ratio and the vertex to be compared with the largest compression ratio in the adjacency list, and determining the current vertex to be processed with the smallest compression ratio among the vertices adjacent to the current starting point in the adjacency list, and then determining the current advancement direction based on the current starting point and the current vertex to be processed, includes:

[0018] An adjacency list is constructed based on each grid vertex in the parameter domain plane, the corresponding vertex compression ratio, and the associated information. The vertex with the smallest vertex compression ratio among all grid vertices is set as the current vertex, and the vertex with the largest vertex compression ratio among all grid vertices is set as the vertex to be compared.

[0019] Based on the adjacency list, determine each adjacent vertex that is adjacent to the current vertex, and determine the adjacent compression ratio corresponding to each of the adjacent vertices. Then, set the vertex corresponding to the smallest compression ratio among the adjacent compression ratios as the current vertex to be processed.

[0020] The current propulsion direction and the current propulsion direction vector are determined based on the first position information of the current starting point in the parameter domain plane and the second position information of the current vertex to be processed in the parameter domain plane.

[0021] Optionally, the step of determining discrete points in the parameter domain plane with the same compression ratio as the current vertex to be processed based on the current compression ratio and current coordinate information of the current vertex to be processed, and determining the current contour lines based on each of the discrete points to be processed and the current propagation direction, includes:

[0022] Based on the preset mesh size and the current propulsion direction vector, the current compression ratio and current coordinate information corresponding to the current vertex to be processed are determined, and each discrete point to be processed with the same compression ratio as the current compression ratio is determined in the parameter domain plane. Then, the discrete point coordinate information corresponding to each discrete point to be processed is determined.

[0023] Using a preset point-line-surface interpolation algorithm and based on the current direction of advancement and current coordinate information, the corresponding gradient value is determined. Based on the gradient value and the coordinate information of each discrete point to be processed, contour line generation is performed on each discrete point to be processed to obtain the current contour line.

[0024] Optionally, determining whether the current compression ratio is greater than the compression ratio threshold corresponding to the vertex to be compared, and if it is not greater, setting the current vertex to be processed as the current starting point and jumping back to the step of determining the current vertex to be processed, until the current compression ratio is greater than the compression ratio threshold, includes:

[0025] Determine the compression ratio threshold corresponding to the vertex to be compared, and then determine whether the current compression ratio is greater than the compression ratio threshold. If the current compression ratio is not greater than the compression ratio threshold, set the current vertex to be processed as the current starting point, and jump back to the step of determining the current vertex to be processed with the smallest compression ratio among the vertices adjacent to the current starting point in the adjacency list, until the current compression ratio is greater than the compression ratio threshold.

[0026] The obtained contour lines are smoothed using a preset Laplace smoothing algorithm to obtain corresponding smooth contour lines. The density of each smooth contour line is then adjusted using a preset automatic adaptive surface curvature change algorithm to obtain target contour lines. The target contour lines are then stored in a preset contour line level set in the order of their generation. The earlier the target contour line is generated, the smaller the level number of the target contour line.

[0027] Optionally, the step of vertically projecting each discrete point on each contour line onto the adjacent outer contour line according to the order in which the contour lines are generated, to obtain projection points, and generating a mesh based on the distance ratio between each discrete point and the corresponding projection point, to obtain a curved quadrilateral-dominated mesh corresponding to the aircraft, includes:

[0028] In ascending order of hierarchy, each discrete point on each target contour line in the preset contour line hierarchy set is vertically projected onto the adjacent outer contour line to obtain the initial projection point corresponding to each discrete point.

[0029] The discrete points are matched with the corresponding initial projection points to obtain matching results. The size of the projection points is determined based on the matching results. The discrete points are then re-projected vertically onto the adjacent outer contour lines based on the size of the projection points to obtain the target projection points.

[0030] Determine the adjacent discrete points of the discrete point on the target contour line, and determine the adjacent projection points of the target projection point on the outer contour line, so as to determine the first distance between the discrete point and the adjacent discrete points and the second distance between the target projection point and the adjacent projection points;

[0031] The distance ratio is determined based on the first distance and the second distance, and the mesh filling rule is determined based on the distance ratio. The mesh is then filled based on the mesh filling rule to obtain a curved quadrilateral dominant mesh corresponding to the aircraft.

[0032] Optionally, determining the mesh filling rule based on the distance ratio, and performing mesh filling based on the mesh filling rule to obtain a curved quadrilateral-dominated mesh corresponding to the aircraft, includes:

[0033] Determine whether the distance ratio is less than a first preset threshold. If the distance ratio is less than the first preset threshold, perform a quadrilateral filling operation on the parameter domain plane to obtain a mesh filling result.

[0034] If the distance ratio is not less than the first preset threshold, then determine whether the distance ratio is less than the second preset threshold. If the distance ratio is less than the second preset threshold, then perform a triangle and a quadrilateral filling operation on the parameter domain plane to obtain a grid filling result.

[0035] If the distance ratio is not less than the second preset threshold, then determine whether the distance ratio is less than the third preset threshold. If the distance ratio is less than the third preset threshold, then perform two triangles and one quadrilateral filling operation on the parameter domain plane to obtain the grid filling result.

[0036] If the distance ratio is not less than the third preset threshold, a new contour line is generated at the midpoint between the target contour line and the outer contour line using a linear interpolation algorithm. A quadrilateral filling operation is performed between the target contour line and the new contour line, and then a triangle filling operation is performed between the new contour line and the outer contour line to obtain the mesh filling result.

[0037] Based on the coordinate positions of each grid vertex in the parameter domain space in the mesh filling result, the mesh filling result is inversely mapped to three-dimensional space to obtain a curved quadrilateral dominant mesh corresponding to the aircraft; the topological relationship between the mesh filling result and the curved quadrilateral dominant mesh is consistent.

[0038] Secondly, this application provides a device for generating a curved quadrilateral dominant mesh for an aircraft, comprising:

[0039] The mesh generation parameter determination module is used to determine the surface mesh generation parameters based on the CAD file of the aircraft, generate an unstructured surface mesh based on the surface mesh generation parameters, conformally map the unstructured surface mesh to a preset parameter domain space to obtain a parameter domain plane, and determine the mesh edge metric corresponding to each mesh vertex in the parameter domain plane, so as to determine the vertex compression rate based on each mesh edge metric.

[0040] The adjacency list determination module is used to determine the adjacency list based on the compression ratio of each vertex, then determine the current starting point with the smallest vertex compression ratio and the vertex to be compared with the largest vertex compression ratio in the adjacency list, and determine the current vertex to be processed with the smallest compression ratio among the vertices adjacent to the current starting point in the adjacency list, and then determine the current advancement direction based on the current starting point and the current vertex to be processed.

[0041] The discrete point determination module is used to determine each discrete point to be processed with the same compression ratio as the current compression ratio in the parameter domain plane based on the current compression ratio and current coordinate information of the current vertex to be processed, and to determine the current contour line based on each discrete point to be processed and the current advancement direction. Then, it determines whether the current compression ratio is greater than the compression ratio threshold corresponding to the vertex to be compared. If it is not greater, the current vertex to be processed is set as the current starting point, and the process jumps back to the step of determining the current vertex to be processed until the current compression ratio is greater than the compression ratio threshold.

[0042] The mesh generation module is used to vertically project each discrete point on each contour line to the adjacent outer contour line according to the order in which the contour lines are generated, to obtain the projection points, and to generate a mesh based on the distance ratio between each discrete point and the corresponding projection point, to obtain a curved quadrilateral dominant mesh corresponding to the aircraft.

[0043] Thirdly, this application provides an electronic device, comprising:

[0044] Memory, used to store computer programs;

[0045] A processor is used to execute the computer program to implement the aforementioned method for generating a curved quadrilateral dominant mesh for an aircraft.

[0046] Fourthly, this application provides a computer-readable storage medium for storing a computer program, wherein the computer program, when executed by a processor, implements the aforementioned method for generating a curved quadrilateral dominant mesh for an aircraft.

[0047] As can be seen from the above, before generating the dominant quadrilateral mesh of the aircraft, this application needs to determine the surface mesh generation parameters based on the aircraft's CAD file, generate the surface unstructured mesh based on the surface mesh generation parameters, then conformally map the surface unstructured mesh to a preset parameter domain space to obtain the parameter domain plane, and determine the mesh edge metric corresponding to each mesh vertex in the parameter domain plane, so as to determine the vertex compression ratio based on each mesh edge metric; determine the adjacency list based on each vertex compression ratio, then determine the current starting point with the smallest vertex compression ratio and the vertex to be compared with the largest vertex compression ratio in the adjacency list, and determine the current vertex to be processed with the smallest compression ratio among the vertices adjacent to the current starting point in the adjacency list, and then determine the current vertex to be processed based on the current starting point and the current vertex to be processed. The forward propulsion direction; based on the current compression ratio and current coordinate information of the current vertex to be processed, determine the discrete points to be processed with the same compression ratio as the current compression ratio in the parameter domain plane, and determine the current contour line based on each discrete point to be processed and the current propulsion direction. Then, determine whether the current compression ratio is greater than the compression ratio threshold corresponding to the vertex to be compared. If it is not greater, set the current vertex to be processed as the current starting point and jump back to the step of determining the current vertex to be processed until the current compression ratio is greater than the compression ratio threshold. According to the order of generation of each contour line, project each discrete point on each contour line vertically to the adjacent outer contour line to obtain the projection point, and generate the mesh based on the distance ratio between each discrete point and the corresponding projection point to obtain the curved quadrilateral dominant mesh corresponding to the spacecraft.

[0048] Therefore, this application first needs to determine the surface mesh generation parameters based on the aircraft's CAD file, and then generate an unstructured surface mesh based on these parameters. Next, the unstructured surface mesh is conformally mapped to a preset parameter domain space to obtain a parameter domain plane. The mesh edge metrics corresponding to each mesh vertex in the parameter domain plane are then determined, and the vertex compression ratio is determined based on these edge metrics. An adjacency list is then determined based on the vertex compression ratios. The current starting point with the smallest compression ratio and the vertex to be compared with the largest compression ratio are then identified in the adjacency list. Finally, the vertex to be processed with the smallest compression ratio among the vertices adjacent to the current starting point is identified in the adjacency list. The current propulsion direction is then determined based on the current starting point and the vertex to be processed. The current compression ratio and coordinate information of the vertex to be processed determine the discrete points in the parameter domain plane that have the same compression ratio as the current vertex. Based on each discrete point and the current propulsion direction, the current contour line is determined. Then, it is determined whether the current compression ratio is greater than the compression ratio threshold corresponding to the vertex to be compared. If not, the current vertex to be processed is set as the current starting point, and the process jumps back to the step of determining the current vertex to be processed until the current compression ratio is greater than the compression ratio threshold. Following the order in which the contour lines are generated, each discrete point on each contour line is vertically projected onto the adjacent outer contour line to obtain projection points. Based on the distance ratio between each discrete point and the corresponding projection point, a mesh is generated to obtain a quadrilateral-dominated mesh corresponding to the aircraft. This improves the efficiency of generating quadrilateral-dominated meshes during the aircraft's quadrilateral-dominated mesh generation process, thereby enhancing the user experience. Attached Figure Description

[0049] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on the provided drawings without creative effort.

[0050] Figure 1 This is a flowchart of a method for generating a curved quadrilateral dominant mesh for an aircraft, as disclosed in this application.

[0051] Figure 2 This is a schematic diagram of a curved quadrilateral dominant mesh generation device for an aircraft disclosed in this application.

[0052] Figure 3 This is a structural diagram of an electronic device disclosed in this application. Detailed Implementation

[0053] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0054] See Figure 1 As shown, this embodiment of the invention discloses a method for generating a curved quadrilateral dominant mesh for an aircraft, including:

[0055] Step S11: Determine the surface mesh generation parameters based on the CAD file of the aircraft, generate an unstructured surface mesh based on the surface mesh generation parameters, then conformally map the unstructured surface mesh to a preset parameter domain space to obtain a parameter domain plane, and determine the mesh edge metric corresponding to each mesh vertex in the parameter domain plane, so as to determine the vertex compression rate based on each mesh edge metric.

[0056] In this embodiment, during the generation of the curved quadrilateral dominant mesh for the aircraft, this application requires reading the IGS digital model information and generating an unstructured mesh based on the parameters corresponding to the digital model information. The detailed steps are as follows: First, the CAD (Computer-Aided Design) digital model IGS (Initial Graphics Exchange Specification) file is read, and surface mesh generation parameters, such as global target size and curvature adaptive angle, are determined based on the CAD digital model IGS file. Then, the surface unstructured mesh M is generated based on the surface mesh generation parameters. Furthermore, the curved mesh is parameterized onto the planar mesh to form a one-to-one mapping relationship. That is, the discrete Ricci (Ricci Curvature) flow is used to conformally map the mesh M to the parameter domain space, thereby obtaining the parameter domain plane N.

[0057] Subsequently, the changes in grid metrics before and after parameterization are calculated and stored at each grid point. In one specific implementation, let... and These represent the metrics of the i-th edge associated with the j-th vertex of meshes M and N, respectively. This represents the calculation of the vertex compression ratio before and after conformal mapping, i.e., the compression ratio of each vertex, and the expression is as follows:

[0058] ;

[0059] Specifically, the step of determining surface mesh generation parameters based on the aircraft's CAD file, generating an unstructured surface mesh based on these parameters, conformally mapping the unstructured surface mesh to a preset parameter domain space to obtain a parameter domain plane, and determining the mesh edge metric corresponding to each mesh vertex in the parameter domain plane, and determining the vertex compression rate based on these edge metric, may include: reading the aircraft's CAD file and determining surface mesh generation parameters including a preset global target size and a preset curvature adaptive angle based on the CAD file, and then using a preset mesh generation algorithm and the surface mesh generation parameters to construct a surface unstructured mesh corresponding to the aircraft. Structured mesh; conformally map the unstructured surface mesh to a preset parameter domain space to obtain a parameter domain plane, and determine the mesh edge metric corresponding to each mesh vertex in the unstructured surface mesh and the parameter domain plane; use the discrete Ricci flow algorithm to map each mesh vertex and associated edge in the unstructured surface mesh to the preset parameter domain space to obtain a parameter domain plane; the preset parameter domain space is a two-dimensional space; the parameter domain plane is a two-dimensional plane; determine the first mesh edge metric corresponding to each mesh vertex in the unstructured surface mesh and the second mesh edge metric corresponding to each mesh vertex in the parameter domain plane, so as to determine the corresponding vertex compression ratio based on the first mesh edge metric and the corresponding second mesh edge metric.

[0060] Step S12: Determine the adjacency list based on the compression ratio of each vertex, then determine the current starting point with the smallest vertex compression ratio and the vertex to be compared with the largest vertex compression ratio in the adjacency list, and determine the current vertex to be processed with the smallest compression ratio among the vertices adjacent to the current starting point in the adjacency list, and then determine the current advancement direction based on the current starting point and the current vertex to be processed.

[0061] In this embodiment, after obtaining the compression ratio of each vertex, the present application embodiment can determine a gradient field in the parameter domain plane based on the vertex compression ratio to obtain contour lines. The specific process is as follows: First, traverse all points, lines, and surfaces in N to establish an adjacency list. Then, find and store the maximum and minimum vertex compression ratios r_max and r_min in the adjacency list. Next, set the vertex corresponding to the minimum value r_min as point A. Then, find the point B with the minimum metric around point A and determine the normalized vector based on point A and point B. and direction of advancement .

[0062] Specifically, the step of determining an adjacency list based on the compression ratios of each vertex, then determining the current starting point with the smallest compression ratio and the vertex to be compared with the largest compression ratio in the adjacency list, and determining the current vertex to be processed with the smallest compression ratio among the vertices adjacent to the current starting point in the adjacency list, and then determining the current advancement direction based on the current starting point and the current vertex to be processed, may include: constructing an adjacency list based on each grid vertex in the parameter domain plane, the corresponding vertex compression ratio, and the associated information, setting the vertex with the smallest compression ratio among the grid vertices as the current vertex, and then setting the vertex with the largest compression ratio among the grid vertices as the vertex to be compared; determining each adjacent vertex adjacent to the current vertex based on the adjacency list, and determining the adjacent compression ratio corresponding to each adjacent vertex, and then setting the vertex corresponding to the smallest compression ratio among the adjacent compression ratios as the current vertex to be processed; and determining the current advancement direction and the current advancement direction vector based on the first position information of the current starting point in the parameter domain plane and the second position information of the current vertex to be processed in the parameter domain plane.

[0063] Step S13: Based on the current compression ratio and current coordinate information of the current vertex to be processed, determine each discrete point to be processed with the same compression ratio as the current compression ratio in the parameter domain plane, and determine the current contour line based on each discrete point to be processed and the current advancement direction. Then, determine whether the current compression ratio is greater than the compression ratio threshold corresponding to the vertex to be compared. If it is not greater, set the current vertex to be processed as the current starting point, and jump back to the step of determining the current vertex to be processed until the current compression ratio is greater than the compression ratio threshold.

[0064] In this embodiment, after obtaining the current propulsion direction and the current propulsion direction vector, this application embodiment needs to obtain the vertex compression ratio corresponding to point B, and then generate the first contour line composed of discrete points according to the point-line-surface interpolation algorithm. Specifically, the step of determining each discrete point to be processed with the same compression ratio as the current vertex to be processed in the parameter domain plane based on the current compression ratio and current coordinate information of the current vertex to be processed, and determining the current contour line based on each discrete point to be processed and the current propulsion direction, may include: determining the current compression ratio and current coordinate information corresponding to the current vertex to be processed based on the preset mesh size and the current propulsion direction vector, determining each discrete point to be processed with the same compression ratio as the current compression ratio in the parameter domain plane, and then determining the discrete point coordinate information corresponding to each discrete point to be processed; using the preset point-line-surface interpolation algorithm and based on the current propulsion direction and current coordinate information to determine the corresponding gradient value, and performing contour line generation operation on each discrete point to be processed based on the gradient value and the discrete point coordinate information corresponding to each discrete point to be processed to obtain the current contour line.

[0065] Furthermore, the process for generating the next contour line is as follows: Set the ratio to the current compression ratio, then determine whether the ratio is less than r_max. If it is less, calculate the size of point B and adjust it according to the direction of advancement. The next point C is calculated, and then the gradient value of point C is calculated to extract the next contour line. It is worth mentioning that in this embodiment, Laplace is used to smooth the contour lines until the loop ends, and then the boundary is processed separately and the boundary lines are stored in a preset contour line set. Specifically, the step of determining whether the current compression ratio is greater than the compression ratio threshold corresponding to the vertex to be compared, and if it is not greater, setting the current vertex to be processed as the current starting point and jumping back to the step of determining the current vertex to be processed, until the current compression ratio is greater than the compression ratio threshold, may include: determining the compression ratio threshold corresponding to the vertex to be compared, and then determining whether the current compression ratio is greater than the compression ratio threshold; if the current compression ratio is not greater than the compression ratio threshold, setting the current vertex to be processed as the current starting point and jumping back to the step of determining the current vertex to be processed with the smallest compression ratio among the vertices adjacent to the current starting point in the adjacency list, until the current compression ratio is greater than the compression ratio threshold; smoothing each obtained contour line using a preset Laplacian smoothing algorithm to obtain corresponding smooth contour lines, and adjusting the contour line density of each smooth contour line using a preset automatic adaptive surface curvature change algorithm to obtain each target contour line, and then storing each target contour line in a preset contour line level set in the order of generation; wherein, the earlier the target contour line is generated, the smaller the level number corresponding to the target contour line.

[0066] Step S14: According to the order in which the contour lines are generated, the discrete points on each contour line are vertically projected onto the adjacent outer contour lines to obtain the projection points. Based on the distance ratio between each discrete point and the corresponding projection point, a mesh is generated to obtain the curved quadrilateral dominant mesh corresponding to the aircraft.

[0067] In this embodiment, after obtaining each contour line, the application requires filling the mesh layer by layer based on discrete points and normal projection points. Specifically, according to the order in which the contour lines are generated, each discrete point on each contour line is vertically projected onto the adjacent outer contour line to obtain projection points. Then, based on the distance ratio between each discrete point and its corresponding projection point, a mesh is generated to obtain a curved quadrilateral-dominated mesh corresponding to the aircraft. This can include: sequentially projecting each discrete point on each target contour line in the preset contour line hierarchy from smallest to largest level onto the adjacent outer contour line to obtain initial projection points corresponding to each discrete point; and then connecting the discrete points with their corresponding initial projection points... The process involves matching lines to obtain matching results, determining the projection point size based on the matching results, and then re-projecting the discrete points vertically onto adjacent outer contour lines based on the projection point size to obtain target projection points. The process also involves determining adjacent discrete points on the target contour line and adjacent projection points on the outer contour line to determine a first distance between the discrete point and its adjacent discrete points, and a second distance between the target projection point and its adjacent projection points. Finally, the process involves determining a distance ratio based on the first distance and the second distance, and then determining a mesh filling rule based on the distance ratio. Mesh filling is then performed based on the mesh filling rule to obtain a curved quadrilateral-dominated mesh corresponding to the aircraft.

[0068] In this embodiment, the steps for filling the grid are as follows: First, obtain the first line l1 of the inner circle and calculate the normal projection points of all discrete points on l1 onto the next contour line l2. Then, match the two points and re-distribute the points on l2 according to the matching results and dimensions. Subsequently, calculate the distance s2 between the two points in l2 and the corresponding distance s1 between the two points on l1.

[0069] In one specific implementation, the embodiments of this application need to determine The value between the value and each preset threshold is used to determine the grid filling method based on the judgment result, and the expression is as follows:

[0070] If( )

[0071] Fill the quadrilateral;

[0072] Else If( )

[0073] Fill in a triangle and a quadrilateral;

[0074] Else If( )

[0075] Fill in two triangles and one quadrilateral.

[0076] It is worth mentioning that if the sizes of two rings differ by more than double, this embodiment of the application requires adding a contour line in the middle and filling it with triangles for transition. Finally, the innermost region is filled with a Denaylay (Delaunaytriangulation algorithm) triangular mesh until every line is filled, thereby completing the parameter domain quadrilateral dominant mesh G.

[0077] It is understandable that, in the process of generating the quadrilateral-dominated mesh, this embodiment of the application needs to inversely map the mesh to three-dimensional space based on the position of the mesh points in the parameter domain mesh N in the mesh filling result, thereby automatically generating the quadrilateral-dominated mesh. Specifically, the step of determining the mesh filling rule based on the distance ratio, and performing mesh filling based on the mesh filling rule to obtain the quadrilateral-dominated mesh corresponding to the aircraft, may include: determining whether the distance ratio is less than a first preset threshold; if the distance ratio is less than the first preset threshold, then performing a quadrilateral filling operation on the parameter domain plane to obtain a mesh filling result; if the distance ratio is not less than the first preset threshold, then determining whether the distance ratio is less than a second preset threshold; if the distance ratio is less than the second preset threshold, then performing a triangle and a quadrilateral filling operation on the parameter domain plane to obtain a mesh filling result; if the distance ratio is not less than the second preset threshold, then determining whether the distance ratio is less than a third preset threshold; if the distance ratio is less than the second preset threshold, then performing a triangle and a quadrilateral filling operation on the parameter domain plane to obtain a mesh filling result; if the distance ratio is not less than the second preset threshold, then determining whether the distance ratio is less than a third preset threshold, and ... If the distance ratio is not less than the third preset threshold, a new contour line is generated at the midpoint between the target contour line and the outer contour line using a linear interpolation algorithm. A quadrilateral filling operation is then performed between the target contour line and the new contour line, followed by a triangle filling operation between the new contour line and the outer contour line, resulting in a mesh filling result. Based on the coordinate positions of each mesh vertex in the parameter domain space, the mesh filling result is inversely mapped to three-dimensional space to obtain a surface quadrilateral-dominated mesh corresponding to the aircraft. The topological relationship between the mesh filling result and the surface quadrilateral-dominated mesh is consistent.

[0078] As can be seen from the above, this application first needs to determine the surface mesh generation parameters based on the aircraft's CAD file, and then generate an unstructured surface mesh based on these parameters. Next, the unstructured surface mesh is conformally mapped to a preset parameter domain space to obtain a parameter domain plane. The mesh edge metrics corresponding to each mesh vertex in the parameter domain plane are then determined, and the vertex compression ratio is determined based on these edge metrics. An adjacency list is then determined based on the vertex compression ratios. The current starting point with the smallest compression ratio and the vertex to be compared with the largest compression ratio are then identified in the adjacency list. Finally, the vertex to be processed with the smallest compression ratio among the vertices adjacent to the current starting point is identified in the adjacency list. The current propulsion direction is then determined based on the current starting point and the vertex to be processed. The current compression ratio and coordinate information of the vertex to be processed determine the discrete points in the parameter domain plane that have the same compression ratio as the current vertex. Based on each discrete point and the current propulsion direction, the current contour line is determined. Then, it is determined whether the current compression ratio is greater than the compression ratio threshold corresponding to the vertex to be compared. If not, the current vertex to be processed is set as the current starting point, and the process jumps back to the step of determining the current vertex to be processed until the current compression ratio is greater than the compression ratio threshold. Following the order in which the contour lines are generated, each discrete point on each contour line is vertically projected onto the adjacent outer contour line to obtain projection points. Based on the distance ratio between each discrete point and the corresponding projection point, a mesh is generated to obtain a quadrilateral-dominated mesh corresponding to the aircraft. This improves the efficiency of generating quadrilateral-dominated meshes during the aircraft's quadrilateral-dominated mesh generation process, thereby enhancing the user experience.

[0079] Accordingly, see Figure 2 As shown, this application also provides a device for generating a curved quadrilateral dominant mesh for an aircraft, comprising:

[0080] The mesh generation parameter determination module 11 is used to determine the surface mesh generation parameters based on the CAD file of the aircraft, generate a surface unstructured mesh based on the surface mesh generation parameters, then conformally map the surface unstructured mesh to a preset parameter domain space to obtain a parameter domain plane, and determine the mesh edge metric corresponding to each mesh vertex in the parameter domain plane, so as to determine the vertex compression rate based on each mesh edge metric.

[0081] The adjacency list determination module 12 is used to determine the adjacency list based on the compression ratio of each vertex, then determine the current starting point with the smallest vertex compression ratio and the vertex to be compared with the largest vertex compression ratio in the adjacency list, and determine the current vertex to be processed with the smallest compression ratio among the vertices adjacent to the current starting point in the adjacency list, and then determine the current advancement direction based on the current starting point and the current vertex to be processed.

[0082] The discrete point determination module 13 is used to determine each discrete point to be processed with the same compression ratio as the current compression ratio in the parameter domain plane based on the current compression ratio and current coordinate information of the current vertex to be processed, and to determine the current contour line based on each discrete point to be processed and the current advancement direction. Then, it determines whether the current compression ratio is greater than the compression ratio threshold corresponding to the vertex to be compared. If it is not greater, the current vertex to be processed is set as the current starting point, and the process jumps back to the step of determining the current vertex to be processed until the current compression ratio is greater than the compression ratio threshold.

[0083] The mesh generation module 14 is used to vertically project each discrete point on each contour line to the adjacent outer contour line according to the order in which the contour lines are generated, to obtain the projection points, and to generate a mesh based on the distance ratio between each discrete point and the corresponding projection point, to obtain a curved quadrilateral dominant mesh corresponding to the aircraft.

[0084] In some specific embodiments, the mesh generation parameter determination module 11 may specifically include:

[0085] An unstructured mesh building unit is used to read the CAD file of the aircraft and determine the surface mesh generation parameters, including the preset global target size and the preset curvature adaptive angle, based on the CAD file, so as to construct the surface unstructured mesh corresponding to the aircraft using a preset mesh generation algorithm and based on the surface mesh generation parameters;

[0086] A mesh conformal mapping unit is used to conformally map the surface unstructured mesh to a preset parameter domain space to obtain a parameter domain plane, and to determine the mesh edge metric corresponding to each mesh vertex in the parameter domain plane and the surface unstructured mesh.

[0087] The parameter domain plane determination unit is used to map each grid vertex and associated edge line in the surface unstructured mesh to a preset parameter domain space using the discrete Ricci flow algorithm to obtain the parameter domain plane; the preset parameter domain space is a two-dimensional space; the parameter domain plane is a two-dimensional plane;

[0088] The vertex compression ratio determination unit is used to determine the first mesh edge metric corresponding to each mesh vertex in the surface unstructured mesh and the second mesh edge metric corresponding to each mesh vertex in the parameter domain plane, so as to determine the corresponding vertex compression ratio based on the first mesh edge metric and the corresponding second mesh edge metric.

[0089] In some specific embodiments, the adjacency list determination module 12 may specifically include:

[0090] The current vertex determination unit is used to construct an adjacency list based on each grid vertex in the parameter domain plane, the corresponding vertex compression ratio, and the association information, and set the vertex with the smallest vertex compression ratio among the grid vertices as the current vertex, and then set the vertex with the largest vertex compression ratio among the grid vertices as the vertex to be compared.

[0091] The current vertex to be processed determination unit is used to determine each adjacent vertex adjacent to the current vertex based on the adjacency list, and to determine the adjacent compression ratio corresponding to each of the adjacent vertices respectively, and then set the vertex corresponding to the smallest compression ratio among the adjacent compression ratios as the current vertex to be processed.

[0092] The current propulsion direction determination unit is used to determine the current propulsion direction and the current propulsion direction vector based on the first position information of the current starting point in the parameter domain plane and the second position information of the current vertex to be processed in the parameter domain plane.

[0093] In some specific embodiments, the discrete point determination module 13 may specifically include:

[0094] The discrete point coordinate information determination unit is used to determine the current compression ratio and current coordinate information corresponding to the current vertex to be processed based on the preset grid size and the current propulsion direction vector, and to determine each discrete point to be processed with the same compression ratio as the current compression ratio in the parameter domain plane, and then determine the discrete point coordinate information corresponding to each discrete point to be processed.

[0095] The current contour line determination unit is used to determine the corresponding gradient value based on the current advancement direction and current coordinate information using a preset point-line-surface interpolation algorithm, and to perform contour line generation operation on each of the discrete points to be processed based on the gradient value and the discrete point coordinate information corresponding to each of the discrete points to be processed, so as to obtain the current contour line.

[0096] In some specific embodiments, the discrete point determination module 13 may specifically include:

[0097] The current starting point update unit is used to determine the compression ratio threshold corresponding to the vertex to be compared, and then determine whether the current compression ratio is greater than the compression ratio threshold. If the current compression ratio is not greater than the compression ratio threshold, the current vertex to be processed is set as the current starting point, and the process jumps back to the step of determining the current vertex to be processed with the smallest compression ratio among the vertices adjacent to the current starting point in the adjacency list, until the current compression ratio is greater than the compression ratio threshold.

[0098] The target contour line generation unit is used to smooth each obtained contour line using a preset Laplace smoothing algorithm to obtain corresponding smooth contour lines, and to adjust the contour line density of each smooth contour line using a preset automatic adaptive surface curvature change algorithm to obtain each target contour line. Then, each target contour line is stored in a preset contour line level set in the order of its generation; wherein, the earlier the target contour line is generated, the smaller the level number corresponding to the target contour line.

[0099] In some specific embodiments, the mesh generation module 14 may specifically include:

[0100] The initial projection point generation unit is used to perform vertical projection operations on each discrete point on each target contour line in the preset contour line hierarchy set to the adjacent outer contour line in order from small to large hierarchy, so as to obtain the initial projection point corresponding to each discrete point.

[0101] The target projection point generation unit is used to match the discrete point with the corresponding initial projection point to obtain the matching result, and determine the projection point size based on the matching result, so as to re-project the discrete point onto the adjacent outer contour line based on the projection point size to obtain the target projection point.

[0102] A distance determination unit is used to determine the adjacent discrete points of the discrete point on the target contour line and to determine the adjacent projection points of the target projection point on the outer contour line, so as to determine the first distance between the discrete point and the adjacent discrete points and the second distance between the target projection point and the adjacent projection points;

[0103] A mesh filling unit is used to determine a distance ratio based on the first distance and the second distance, and to determine a mesh filling rule based on the distance ratio, so as to perform mesh filling based on the mesh filling rule to obtain a curved quadrilateral dominant mesh corresponding to the aircraft.

[0104] In some specific embodiments, the mesh generation module 14 may specifically include:

[0105] The first grid filling result determination unit is used to determine whether the distance ratio is less than a first preset threshold. If the distance ratio is less than the first preset threshold, a quadrilateral filling operation is performed on the parameter domain plane to obtain the grid filling result.

[0106] The second mesh filling result determination unit is used to determine whether the distance ratio is less than the second preset threshold if the distance ratio is not less than the first preset threshold, and if the distance ratio is less than the second preset threshold, to perform a triangle and a quadrilateral filling operation on the parameter domain plane to obtain the mesh filling result.

[0107] The third grid filling result determination unit is used to determine whether the distance ratio is less than the third preset threshold if the distance ratio is not less than the second preset threshold, and if the distance ratio is less than the third preset threshold, to perform two triangles and one quadrilateral filling operation on the parameter domain plane to obtain the grid filling result.

[0108] The fourth grid filling result determination unit is used to generate a new contour line at the midpoint of the target contour line and the outer contour line using a linear interpolation algorithm if the distance ratio is not less than the third preset threshold. Then, a quadrilateral filling operation is performed between the target contour line and the new contour line, and a triangle filling operation is performed between the new contour line and the outer contour line to obtain the grid filling result.

[0109] The mesh filling result inverse mapping unit is used to inversely map the mesh filling result to three-dimensional space based on the coordinate positions of each mesh vertex in the parameter domain space, to obtain a surface quadrilateral dominant mesh corresponding to the aircraft; the mesh filling result is consistent with the topological relationship corresponding to the surface quadrilateral dominant mesh.

[0110] Furthermore, embodiments of this application also disclose an electronic device, Figure 3 This is a structural diagram of an electronic device 20 according to an exemplary embodiment. The content of the diagram should not be construed as limiting the scope of this application. Specifically, the electronic device 20 may include: at least one processor 21, at least one memory 22, a power supply 23, a communication interface 24, an input / output interface 25, and a communication bus 26. The memory 22 stores a computer program, which is loaded and executed by the processor 21 to implement the relevant steps in the method for generating the curved quadrilateral dominant mesh of an aircraft disclosed in any of the foregoing embodiments. Furthermore, the electronic device 20 in this embodiment may specifically be an electronic computer.

[0111] In this embodiment, the power supply 23 is used to provide operating voltage for each hardware device on the electronic device 20; the communication interface 24 can create a data transmission channel between the electronic device 20 and external devices, and the communication protocol it follows can be any communication protocol applicable to the technical solution of this application, and is not specifically limited here; the input / output interface 25 is used to acquire external input data or output data to the outside world, and its specific interface type can be selected according to specific application needs, and is not specifically limited here.

[0112] In addition, the memory 22, as a carrier for resource storage, can be a read-only memory, random access memory, disk or optical disk, etc. The resources stored thereon can include operating system 221, computer program 222, etc., and the storage method can be temporary storage or permanent storage.

[0113] The operating system 221 is used to manage and control the various hardware devices on the electronic device 20 and the computer program 222, which may be Windows Server, Netware, Unix, Linux, etc. In addition to including a computer program capable of performing the method for generating a curved quadrilateral dominant mesh for an aircraft executed by the electronic device 20 as disclosed in any of the foregoing embodiments, the computer program 222 may further include computer programs capable of performing other specific tasks.

[0114] Furthermore, this application also discloses a computer-readable storage medium for storing a computer program; wherein, when the computer program is executed by a processor, it implements the aforementioned method for generating a curved quadrilateral dominant mesh for an aircraft. Specific steps of this method can be found in the corresponding content disclosed in the foregoing embodiments, and will not be repeated here.

[0115] The various embodiments in this specification are described in a progressive manner, with each embodiment focusing on its differences from other embodiments. Similar or identical parts between embodiments can be referred to interchangeably. For the apparatus disclosed in the embodiments, since it corresponds to the method disclosed in the embodiments, the description is relatively simple; relevant parts can be referred to in the method section.

[0116] Those skilled in the art will further recognize that the units and algorithm steps of the various examples described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, computer software, or a combination of both. To clearly illustrate the interchangeability of hardware and software, the components and steps of the various examples have been generally described in terms of functionality in the foregoing description. Whether these functions are implemented in hardware or software depends on the specific application and design constraints of the technical solution. Those skilled in the art can use different methods to implement the described functions for each specific application, but such implementation should not be considered beyond the scope of this application.

[0117] The steps of the methods or algorithms described in conjunction with the embodiments disclosed herein can be implemented directly by hardware, a software module executed by a processor, or a combination of both. The software module can be located in random access memory (RAM), main memory, read-only memory (ROM), electrically programmable ROM, electrically erasable programmable ROM, registers, hard disk, removable disk, CD-ROM, or any other form of storage medium known in the art.

[0118] Finally, it should be noted that in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0119] The technical solutions provided in this application have been described in detail above. Specific examples have been used to illustrate the principles and implementation methods of this application. The descriptions of the above embodiments are only for the purpose of helping to understand the methods and core ideas of this application. At the same time, for those skilled in the art, there will be changes in the specific implementation methods and application scope based on the ideas of this application. Therefore, the content of this specification should not be construed as a limitation of this application.

Claims

1. A method for generating a curved quadrilateral-dominant mesh of an aircraft, characterized in that, The method comprises the following steps: determining surface mesh generation parameters based on a CAD file of the aircraft, generating a surface unstructured mesh based on the surface mesh generation parameters, conformally mapping the surface unstructured mesh to a preset parameter domain space to obtain a parameter domain plane, and determining mesh edge metrics corresponding to each grid vertex of the surface unstructured mesh and the parameter domain plane, and determining vertex compression rates based on the mesh edge metrics; determining an adjacency table based on the vertex compression rates, determining a current starting point with the minimum vertex compression rate and a vertex to be compared with the maximum vertex compression rate in the adjacency table, determining a current to-be-processed vertex with the minimum compression rate among vertices adjacent to the current starting point in the adjacency table, and determining a current advancing direction based on the current starting point and the current to-be-processed vertex; determining, in the parameter domain plane, each to-be-processed discrete point with the same compression rate as the current compression rate based on the current compression rate and the current coordinate information of the current to-be-processed vertex, determining a current contour based on each to-be-processed discrete point and the current advancing direction, and determining whether the current compression rate is greater than a compression rate threshold corresponding to the vertex to be compared, and if not, setting the current to-be-processed vertex as the current starting point and returning to the step of determining the current to-be-processed vertex until the current compression rate is greater than the compression rate threshold; vertically projecting each discrete point on each contour to an adjacent outer contour in the order of generation of each contour to obtain a projection point, and generating a mesh based on the distance ratio between each discrete point and the corresponding projection point to obtain a curved quadrilateral dominant mesh corresponding to the aircraft.

2. The method of claim 1, wherein, The method of determining surface mesh generation parameters based on a CAD file of the aircraft, generating a surface unstructured mesh based on the surface mesh generation parameters, conformally mapping the surface unstructured mesh to a preset parameter domain space to obtain a parameter domain plane, and determining mesh edge metrics corresponding to each grid vertex of the surface unstructured mesh and the parameter domain plane, and determining vertex compression rates based on the mesh edge metrics, comprises the following steps: reading the CAD file of the aircraft and determining surface mesh generation parameters including a preset global target size and a preset curvature adaptive angle based on the CAD file, and constructing a surface unstructured mesh corresponding to the aircraft by using a preset mesh generation algorithm and based on the surface mesh generation parameters; conformally mapping the surface unstructured mesh to a preset parameter domain space to obtain a parameter domain plane, and determining mesh edge metrics corresponding to each grid vertex of the surface unstructured mesh and the parameter domain plane; mapping each grid vertex and the associated edge line of the surface unstructured mesh to a preset parameter domain space by using a discrete Ricci flow algorithm to obtain a parameter domain plane; the preset parameter domain space is a two-dimensional space; and the parameter domain plane is a two-dimensional plane; determining first mesh edge metrics corresponding to each grid vertex of the surface unstructured mesh and second mesh edge metrics corresponding to each grid vertex of the parameter domain plane, and determining corresponding vertex compression rates based on the first mesh edge metrics and the corresponding second mesh edge metrics.

3. The method of claim 1, wherein, Determine the current starting point with the minimum vertex compression rate and the vertex to be compared with the maximum vertex compression rate in the adjacency list based on the vertex compression rate of each vertex, and determine the current vertex to be processed with the minimum compression rate among the vertices adjacent to the current starting point in the adjacency list, and then determine the current advancing direction based on the current starting point and the current vertex to be processed, including: Construct the adjacency list based on each grid vertex in the parameter domain plane, the corresponding vertex compression rate and the associated information, and set the vertex with the minimum vertex compression rate among each grid vertex as the current vertex, and then set the vertex with the maximum vertex compression rate among each grid vertex as the vertex to be compared; Determine each adjacent vertex adjacent to the current vertex based on the adjacency list, and determine the adjacent compression rate corresponding to each adjacent vertex, and then set the vertex corresponding to the minimum compression rate among each adjacent compression rate as the current vertex to be processed; Determine the current advancing direction and the current advancing direction vector based on the first position information of the current starting point in the parameter domain plane and the second position information of the current vertex to be processed in the parameter domain plane.

4. The method of claim 3, wherein, Determine each vertex to be processed with the same compression rate as the current compression rate in the parameter domain plane based on the current compression rate and the current coordinate information of the current vertex to be processed, and determine the current contour line based on each vertex to be processed and the current advancing direction, including: Determine the current compression rate and the current coordinate information corresponding to the current vertex to be processed based on the preset grid size and the current advancing direction vector, and determine each vertex to be processed with the same compression rate as the current compression rate in the parameter domain plane, and then determine the discrete point coordinate information corresponding to each vertex to be processed; Determine the corresponding gradient value based on the current advancing direction and the current coordinate information by using the preset point-line-surface interpolation algorithm, and perform contour generation operation on each vertex to be processed based on the gradient value and the discrete point coordinate information corresponding to each vertex to be processed, to obtain the current contour line.

5. The method of claim 1, wherein, Determine whether the current compression rate is greater than the compression rate threshold value corresponding to the vertex to be compared, if not, set the current vertex to be processed as the current starting point, and jump back to the step of determining the current vertex to be processed until the current compression rate is greater than the compression rate threshold value, including: Determine the compression rate threshold value corresponding to the vertex to be compared, and then determine whether the current compression rate is greater than the compression rate threshold value, if the current compression rate is not greater than the compression rate threshold value, set the current vertex to be processed as the current starting point, and jump back to the step of determining the current vertex to be processed among the vertices adjacent to the current starting point in the adjacency list until the current compression rate is greater than the compression rate threshold value; The obtained each contour line is smoothed by using a preset Laplace smoothing processing algorithm to obtain corresponding smoothed contour lines, and the density of each smoothed contour line is adjusted by using a preset automatic adaptive curved surface curvature change algorithm to obtain each target contour line, and then each target contour line is sequentially stored in a preset contour level set according to the generation order; the earlier the target contour line is generated, the smaller the level number corresponding to the target contour line is.

6. The method of claim 5, wherein, The vertical projection of each discrete point on each contour line to the adjacent outer contour line is performed according to the generation order of each contour line to obtain a projection point, and a grid is generated based on the distance ratio between each discrete point and the corresponding projection point to obtain a curved quadrilateral dominant grid corresponding to the aircraft, including: The vertical projection of each discrete point on each target contour line in the preset contour level set to the adjacent outer contour line is performed in turn according to the order of the level from small to large to obtain an initial projection point corresponding to each discrete point; The discrete point and the corresponding initial projection point are matched to obtain a matching result, and the projection point size is determined based on the matching result, so that the discrete point is re-projected vertically to the adjacent outer contour line based on the projection point size to obtain a target projection point; The adjacent discrete point of the discrete point on the target contour line is determined, and the adjacent projection point of the target projection point on the outer contour line is determined, so that the first distance between the discrete point and the adjacent discrete point and the second distance between the target projection point and the adjacent projection point are determined; The distance ratio is determined based on the first distance and the second distance, and the grid filling rule is determined based on the distance ratio, so that the grid filling is performed based on the grid filling rule to obtain a curved quadrilateral dominant grid corresponding to the aircraft.

7. The method of claim 6, wherein, The distance ratio is determined based on the first distance and the second distance, and the grid filling rule is determined based on the distance ratio, so that the grid filling is performed based on the grid filling rule to obtain a curved quadrilateral dominant grid corresponding to the aircraft. It is judged whether the distance ratio is less than a first preset threshold, if the distance ratio is less than the first preset threshold, a quadrilateral filling operation is performed on the parameter domain plane to obtain a grid filling result; If the distance ratio is not less than the first preset threshold, it is judged whether the distance ratio is less than a second preset threshold, if the distance ratio is less than the second preset threshold, a filling operation of one triangle and one quadrilateral is performed on the parameter domain plane to obtain a grid filling result; If the distance ratio is not less than the second preset threshold, it is judged whether the distance ratio is less than a third preset threshold, if the distance ratio is less than the third preset threshold, a filling operation of two triangles and one quadrilateral is performed on the parameter domain plane to obtain a grid filling result; If the distance ratio is not less than the third preset threshold, a new contour line is generated at a midpoint position of the target contour line and the outer contour line by using a linear interpolation algorithm, a quadrilateral filling operation is performed between the target contour line and the new contour line, and then a triangular filling operation is performed between the new contour line and the outer contour line, to obtain a grid filling result; The grid filling result is inversely mapped to a three-dimensional space based on coordinate positions of each grid vertex in the grid filling result in the parameter domain space, to obtain a curved quadrilateral dominant grid corresponding to the aircraft; and a topological relationship corresponding to the grid filling result and the curved quadrilateral dominant grid is consistent.

8. A device for generating a curved quadrilateral dominant mesh for an aircraft, characterized in that, Comprise: A grid generation parameter determination module is configured to determine surface grid generation parameters based on a CAD file of the aircraft, to generate a surface unstructured grid based on the surface grid generation parameters, to conformally map the surface unstructured grid to a preset parameter domain space to obtain a parameter domain plane, and to determine grid edge metrics corresponding to each grid vertex in the surface unstructured grid and the parameter domain plane, to determine vertex compression rates based on each grid edge metric; An adjacency list determination module is configured to determine an adjacency list based on each vertex compression rate, to determine a current starting point with a minimum vertex compression rate and a vertex to be compared with a maximum vertex compression rate in the adjacency list, to determine a current vertex to be processed with a minimum compression rate among each vertex adjacent to the current starting point in the adjacency list, and to determine a current advancing direction based on the current starting point and the current vertex to be processed; A discrete point determination module is configured to determine each vertex to be processed discrete point with a same compression rate as the current compression rate of the current vertex to be processed in the parameter domain plane based on the current compression rate and current coordinate information of the current vertex to be processed, and to determine a current contour line based on each vertex to be processed discrete point and the current advancing direction, and to determine whether the current compression rate is greater than a compression rate threshold corresponding to the vertex to be compared, and if not, to set the current vertex to be processed as the current starting point, and to return to the step of determining the current vertex to be processed until the current compression rate is greater than the compression rate threshold; A grid generation module is configured to project each discrete point on each contour line to an adjacent outer contour line to obtain a projection point in a vertical direction according to a sequence in which each contour line is generated, and to generate a curved quadrilateral dominant grid corresponding to the aircraft based on a distance ratio between each discrete point and the corresponding projection point.

9. An electronic device, comprising: Comprise: A memory is configured to save a computer program; A processor is configured to execute the computer program to implement the curved quadrilateral dominant grid generation method of the aircraft according to any one of claims 1 to 7.

10. A computer-readable storage medium, characterized in that, A computer program is saved, and the computer program is executed by a processor to implement the curved quadrilateral dominant grid generation method of the aircraft according to any one of claims 1 to 7.

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