Method, device and equipment for generating curved-surface quadrilateral dominant grid of aircraft and storage medium

Abstract

The invention discloses a curved surface quadrilateral dominant grid generation method, device and equipment for an aircraft and a storage medium, and relates to the technical field of computational fluid mechanics, and the method comprises the steps: creating a surface unstructured grid based on surface grid generation parameters of a CAD file of the aircraft, carrying out the conformal mapping of the surface unstructured grid to a parameter domain plane, and calculating the vertex compression ratio of each grid vertex; selecting the current starting point with the minimum compression ratio and the maximum to-be-compared vertex in the adjacency list, and determining the current to-be-processed vertex with the minimum compression ratio in the adjacent vertexes and the advancing direction; determining to-be-processed discrete points according to the current compression ratio and the coordinate information to generate a current isoline, if the current compression ratio does not exceed a threshold value, iteratively updating the current starting point, and skipping to the step of determining the current to-be-processed vertex again; the discrete points are projected to the outer-layer isolines according to the isoline sequence, and the curved-surface quadrilateral dominant grid is generated based on the distance proportion between each discrete point and the projection point, so that the generation efficiency of the curved-surface quadrilateral grid is improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of computational fluid dynamics, in particular to a curved quadrilateral-dominant mesh generation method, device and equipment of an aircraft and a storage medium. BACKGROUND

[0002] At present, quadrilateral-dominant mesh has significant advantages in engineering simulation, geometric modeling, parameterization and other fields. Under the same number of elements, quadrilateral elements have higher interpolation accuracy and convergence than triangular elements. The balance problem of the essential geometric constraints, topological rules and computational efficiency of quadrilateral-dominant mesh generation needs to meet the global constraints of differential geometry, singular point index and, compatible with noise mesh, multi-boundary conditions, and control the post-processing overhead.

[0003] The existing quadrilateral-dominant mesh generation method, the classic Q-Morph front advancing method, advances quadrilateral elements from the boundary inward, merges triangular meshes into quadrilateral meshes, and avoids residual triangles through active front management. The region decomposition method recursively divides the complex domain into simple subdomains, and generates subdomain meshes using predefined templates. The frame field method defines the edge direction of the mesh through the frame field, generates a topological partition combined with curvature constraints, advances quadrilateral meshes in the partition and fills a small number of triangles. There are still problems such as input quality dependence, extreme geometric adaptability and three-dimensional expansion.

[0004] However, the above existing technology is difficult to balance in mathematical constraints and feature preservation, and the optimization of singular point distribution still depends on artificial experience, and the computational complexity of large-scale models is high, which greatly reduces the mesh generation efficiency. Complex meshes are prone to geometric cracks and need to rely on post-processing, which may cause certain problems.

[0005] From the above, how to improve the efficiency of generating curved quadrilateral-dominant mesh in the process of generating curved quadrilateral-dominant mesh of an aircraft is a problem to be solved at present. SUMMARY

[0006] Therefore, the purpose of the present application is to provide a curved quadrilateral-dominant mesh generation method, device and equipment of an aircraft and a storage medium, which can improve the efficiency of generating curved quadrilateral-dominant mesh in the process of generating curved quadrilateral-dominant mesh of an aircraft, thereby improving the user's experience. The specific scheme is as follows:

[0007] In a first aspect, the present application provides a curved quadrilateral-dominant mesh generation method of an aircraft, comprising:

[0008] determine surface mesh generation parameters based on the CAD file of the aircraft, generate a surface unstructured mesh based on the surface mesh generation parameters, conformally map the surface unstructured mesh to a preset parameter domain space to obtain a parameter domain plane, and determine mesh edge metrics corresponding to each grid vertex of the surface unstructured mesh and the parameter domain plane, to determine vertex compression rates based on each mesh edge metric;

[0009] determine an adjacency table based on each vertex compression rate, determine a current starting point with the smallest vertex compression rate and a vertex to be compared with the largest vertex compression rate in the adjacency table, determine a current vertex to be processed with the smallest compression rate among each vertex adjacent to the current starting point in the adjacency table, and determine a current advancing direction based on the current starting point and the current vertex to be processed;

[0010] determine each discrete point 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, determine a current contour based on each discrete point to be processed and the current advancing direction, and determine whether the current compression rate is greater than a compression rate threshold corresponding to the vertex to be compared, and if not, set the current vertex to be processed as the current starting point and re-jump to the step of determining the current vertex to be processed until the current compression rate is greater than the compression rate threshold;

[0011] vertically project 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 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.

[0012] Optionally, the surface mesh generation parameters are determined based on the CAD file of the aircraft, the surface unstructured mesh is generated based on the surface mesh generation parameters, the surface unstructured mesh is conformally mapped to a preset parameter domain space to obtain a parameter domain plane, and the mesh edge metrics corresponding to each grid vertex of the surface unstructured mesh and the parameter domain plane are determined, to determine the vertex compression rates based on each mesh edge metric, which includes:

[0013] read the CAD file of the aircraft, determine the surface mesh generation parameters including a preset global target size and a preset curvature adaptive angle based on the CAD file, and construct a surface unstructured mesh corresponding to the aircraft by using a preset mesh generation algorithm and based on the surface mesh generation parameters;

[0014] conformally map the surface unstructured mesh to a preset parameter domain space to obtain a parameter domain plane, and determine mesh edge metrics corresponding to each grid vertex of the surface unstructured mesh and the parameter domain plane;

[0015] mapping each grid vertex and the associated edge in 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.

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

[0017] Optionally, the adjacent table is determined based on the vertex compression rates, and then a current starting point with the minimum vertex compression rate in the adjacent table and a vertex to be compared with the maximum vertex compression rate are determined, and a current vertex to be processed with the minimum compression rate among the vertices adjacent to the current starting point in the adjacent table is determined, and then a current advancing direction is determined based on the current starting point and the current vertex to be processed, including:

[0018] an adjacent table is constructed based on each grid vertex in the parameter domain plane, the corresponding vertex compression rate and the associated information, and a vertex with the minimum vertex compression rate among the grid vertices is set as a current vertex, and then a vertex with the maximum vertex compression rate among the grid vertices is set as a vertex to be compared;

[0019] each adjacent vertex adjacent to the current vertex is determined based on the adjacent table, and a corresponding adjacent compression rate of each adjacent vertex is determined, and then a vertex corresponding to the compression rate with the minimum value among the adjacent compression rates is set as a current vertex to be processed;

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

[0021] Optionally, each vertex to be processed with the same compression rate as the current compression rate is determined in the parameter domain plane based on the current compression rate and the current coordinate information of the current vertex to be processed, and a current contour line is determined based on each vertex to be processed and the current advancing direction, including:

[0022] current compression rate and current coordinate information corresponding to the current vertex to be processed are determined based on a preset grid size and the current advancing direction vector, and each vertex to be processed with the same compression rate as the current compression rate is determined in the parameter domain plane, and then discrete point coordinate information corresponding to each vertex to be processed is determined;

[0023] The preset point-line-surface interpolation algorithm is used to determine a corresponding gradient value based on the current advancing direction and the current coordinate information, and an isogram generation operation is performed on each of the discrete points to be processed based on the gradient value and discrete point coordinate information corresponding to each of the discrete points to be processed, so as to obtain a current isogram.

[0024] Optionally, the method further comprises: determining a compression rate threshold corresponding to the vertex to be compared; and determining whether the current compression rate is greater than the compression rate threshold.

[0025] Optionally, the method further comprises: determining a compression rate threshold corresponding to the vertex to be compared; and determining whether the current compression rate is greater than the compression rate threshold.

[0026] The obtained isograms are subjected to a preset Laplace smoothing processing algorithm to obtain corresponding smoothed isograms, and a preset automatic adaptive surface curvature change algorithm is used to adjust the isogram density of each of the smoothed isograms to obtain target isograms, and then each of the target isograms is sequentially stored in a preset isogram hierarchical set according to the generation order; wherein the earlier the target isogram is generated, the smaller the hierarchical series corresponding to the target isogram is.

[0027] Optionally, the method further comprises: vertically projecting each of the discrete points on each of the isograms to an adjacent outer isogram to obtain a projection point, and performing grid generation based on the distance ratio between each of the discrete points and the corresponding projection point to obtain a curved quadrilateral grid corresponding to the aircraft.

[0028] The vertical projection operation is sequentially performed on each of the discrete points on each of the target isograms in the preset isogram hierarchical set to an adjacent outer isogram according to the order of the hierarchical series from small to large to obtain an initial projection point corresponding to each of the discrete points.

[0029] The discrete points and the corresponding initial projection points are matched to obtain a matching result, and the projection point size is determined based on the matching result, so that the vertical projection operation is performed on the discrete points to the adjacent outer isogram based on the projection point size to obtain a target projection point.

[0030] determining a neighboring discrete point of the discrete point on the target contour line and a neighboring projection point of the target projection point on the outer contour line to determine a first distance between the discrete point and the neighboring discrete point and a second distance between the target projection point and the neighboring projection point;

[0031] determining a distance ratio based on the first distance and the second distance, and determining a grid filling rule based on the distance ratio to perform grid filling based on the grid filling rule to obtain the curved quadrilateral-dominant grid corresponding to the aircraft.

[0032] Optionally, the determining the grid filling rule based on the distance ratio to perform grid filling based on the grid filling rule to obtain the curved quadrilateral-dominant grid corresponding to the aircraft comprises:

[0033] determining whether the distance ratio is less than a first preset threshold, and if the distance ratio is less than the first preset threshold, performing a quadrilateral filling operation on the parameter domain plane to obtain a grid filling result;

[0034] if the distance ratio is not less than the first preset threshold, determining whether the distance ratio is less than a second preset threshold, and if the distance ratio is less than the second preset threshold, performing a filling operation of one triangle and one quadrilateral on the parameter domain plane to obtain a grid filling result;

[0035] if the distance ratio is not less than the second preset threshold, determining whether the distance ratio is less than a third preset threshold, and if the distance ratio is less than the third preset threshold, performing a filling operation of two triangles and one quadrilateral on the parameter domain plane to obtain a grid filling result;

[0036] if the distance ratio is not less than the third preset threshold, generating a new contour line at a midpoint position of the target contour line and the outer contour line by using a linear interpolation algorithm, and performing a filling operation of quadrilaterals between the target contour line and the new contour line, and then performing a filling operation of triangles between the new contour line and the outer contour line to obtain a grid filling result;

[0037] inverse mapping the grid filling result 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 the 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.

[0038] In a second aspect, the present application provides a curved quadrilateral-dominant grid generation device for an aircraft, comprising:

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

[0040] an adjacency table determination module configured to determine an adjacency table based on each vertex compression rate, to determine a current starting point with a minimum vertex compression rate and a to-be-compared vertex with a maximum vertex compression rate in the adjacency table, and to determine a current to-be-processed vertex with a minimum compression rate among vertices adjacent to the current starting point in the adjacency table, so as to determine a current advancing direction based on the current starting point and the current to-be-processed vertex;

[0041] a discrete point determination module configured to determine to-be-processed discrete points with the same compression rate as the current compression rate of the current to-be-processed vertex and current coordinate information in the parameter domain plane, to determine a current contour based on each 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 to-be-compared vertex, and if not, to set the current to-be-processed vertex as the current starting point and re-jump to the step of determining the current to-be-processed vertex until the current compression rate is greater than the compression rate threshold;

[0042] a mesh generation module configured to project each discrete point on each contour to a neighboring outer contour in a vertical direction according to a sequence in which each contour is generated to obtain a projection point, and to generate a mesh based on a distance ratio between each discrete point and the corresponding projection point to obtain a curved quadrilateral dominant mesh corresponding to the aircraft.

[0043] In a third aspect, the present application provides an electronic device, comprising:

[0044] a memory configured to save a computer program;

[0045] a processor configured to execute the computer program to implement the curved quadrilateral dominant mesh generation method of the aircraft.

[0046] In a fourth aspect, the present application provides a computer readable storage medium configured to save a computer program, wherein the computer program is executed by a processor to implement the curved quadrilateral dominant mesh generation method of the aircraft.

[0047] As can be seen from the above, before the curved quadrilateral dominant mesh of the aircraft is generated, the surface mesh generation parameters are determined based on the CAD file of the aircraft, the surface unstructured mesh is generated based on the surface mesh generation parameters, then the surface unstructured mesh is conformally mapped to the preset parameter domain space to obtain a parameter domain plane, and the grid edge metric corresponding to each grid vertex in the surface unstructured mesh and the parameter domain plane is determined to determine the vertex compression rate based on each grid edge metric; the adjacent table is determined based on each vertex compression rate, then the current starting point with the minimum vertex compression rate and the vertex to be compared with the maximum vertex compression rate in the adjacent table are determined, and the current to-be-processed vertex with the minimum compression rate in each vertex adjacent to the current starting point in the adjacent table is determined, then the current advancing direction is determined based on the current starting point and the current to-be-processed vertex; each to-be-processed discrete point with the same compression rate as the current compression rate is determined in the parameter domain plane based on the current compression rate and the current coordinate information of the current to-be-processed vertex, and the current contour is determined based on each to-be-processed discrete point and the current advancing direction, then it is judged whether the current compression rate is greater than the compression rate threshold corresponding to the vertex to be compared, if not, the current to-be-processed vertex is set as the current starting point, and the step of determining the current to-be-processed vertex is re-jumped until the current compression rate is greater than the compression rate threshold; each discrete point on each contour is vertically projected to the adjacent outer contour in the order of generation of each contour to obtain a projection point, and the grid is generated based on the distance ratio between each discrete point and the corresponding projection point to obtain the curved quadrilateral dominant mesh corresponding to the aircraft.

[0048] It can be seen that the application first needs to determine the surface mesh generation parameters based on the CAD file of the aircraft, generate the surface unstructured mesh based on the surface mesh generation parameters, conformally map the surface unstructured mesh to the preset parameter domain space to obtain the parameter domain plane, and determine the grid edge metric corresponding to each grid vertex in the surface unstructured mesh and the parameter domain plane, to determine the vertex compression rate based on each grid edge metric; determine the current starting point with the smallest vertex compression rate and the vertex to be compared with the largest vertex compression rate in the adjacency table based on each vertex compression rate, and determine the current to-be-processed vertex with the smallest compression rate among the vertices adjacent to the current starting point in the adjacency table, and then determine the current advancing direction based on the current starting point and the current to-be-processed vertex; determine the to-be-processed discrete points 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 to-be-processed vertex, and determine the current contour based on the current to-be-processed discrete points and the current advancing direction, and then determine whether the current compression rate is greater than the compression rate threshold corresponding to the vertex to be compared, if not, set the current to-be-processed vertex as the current starting point, and jump back to the step of determining the current to-be-processed vertex until the current compression rate is greater than the compression rate threshold; project each discrete point on each contour to the adjacent outer contour in the vertical direction according to the order of generation of each contour to obtain the projection point, and generate the grid based on the distance ratio between each discrete point and the corresponding projection point to obtain the curved surface quadrilateral dominant mesh corresponding to the aircraft. In this way, the efficiency of generating the curved surface quadrilateral dominant mesh is improved in the process of generating the curved surface quadrilateral dominant mesh of the aircraft, thereby improving the user experience. BRIEF DESCRIPTION OF DRAWINGS

[0049] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the following will briefly introduce the drawings needed to be used in the embodiments or the prior art description. Obviously, the drawings in the following description are only embodiments of the present application, and for those skilled in the art, other drawings can also be obtained without creative labor based on the provided drawings.

[0050] Figure 1 A flow chart of a curved surface quadrilateral dominant mesh generation method of an aircraft disclosed by the present application;

[0051] Figure 2 A structural schematic diagram of a curved surface quadrilateral dominant mesh generation device of an aircraft disclosed by the present application;

[0052] Figure 3 A structural diagram of an electronic device disclosed by the present application. DETAILED DESCRIPTION

[0053] With reference to the drawings and embodiments of the present application, the technical solutions in the embodiments of the present application will be described clearly and completely. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments of the present application, all other embodiments obtained by those skilled in the art without creative work fall within the scope of the present application.

[0054] Referring to Figure 1 As shown in the drawings, the embodiments of the present application disclose a curved quadrilateral dominant mesh generation method of an aircraft, comprising:

[0055] In step S11, surface mesh generation parameters are determined based on a CAD file of the aircraft, a surface unstructured mesh is generated based on the surface mesh generation parameters, the surface unstructured mesh is conformally mapped to a preset parameter domain space to obtain a parameter domain plane, and a mesh edge metric corresponding to each mesh vertex in the surface unstructured mesh and the parameter domain plane is determined, so as to determine a vertex compression rate based on each mesh edge metric.

[0056] In the embodiments, during the generation of the curved quadrilateral dominant mesh of the aircraft, the embodiments of the present application need to read igs digital model information, and generate an unstructured mesh according to parameters corresponding to the digital model information, and the detailed steps are as follows: first, a CAD (Computer-Aided Design) digital model IGS (Initial Graphics Exchange Specification) file is read, and surface mesh generation parameters such as global target size, curvature adaptive angle and the like are determined based on the CAD digital model IGS file, then a surface unstructured mesh M is generated based on the surface mesh generation parameters. Further, the curved mesh is parameterized to a plane mesh to form a one-to-one mapping relationship, that is, the mesh M is conformally mapped to a parameter domain space by using a discrete Ricci (Ricci Curvature) flow, so as to obtain a parameter domain plane N.

[0057] Subsequently, the change of the mesh metric before and after parameterization is calculated and stored on each mesh point. In a specific embodiment, let and respectively represent the i-th mesh edge metric associated with the j-th mesh vertex of the meshes M and N, represent the calculated metric vertex compression rate values before and after the conformal mapping processing, that is, the compression rate of each vertex, and the expression is as follows:

[0058] ;

[0059] Specifically, the method can comprise the following steps: reading a 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, to construct 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 a mesh edge metric corresponding to each mesh vertex in the surface unstructured mesh and the parameter domain plane; mapping each mesh vertex and an associated edge line in the surface unstructured mesh to the 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; the parameter domain plane is a two-dimensional plane; determining a first mesh edge metric corresponding to each mesh vertex in the surface unstructured mesh and a second mesh edge metric corresponding to each mesh vertex in the parameter domain plane, to determine a corresponding vertex compression rate based on the first mesh edge metric and the corresponding second mesh edge metric.

[0060] In step S12, an adjacency table is determined based on the vertex compression rates, a current starting point with the minimum vertex compression rate and a to-be-compared vertex with the maximum vertex compression rate in the adjacency table are determined, a current to-be-processed vertex with the minimum compression rate among vertices adjacent to the current starting point in the adjacency table is determined, and a current advancing direction is determined based on the current starting point and the current to-be-processed vertex.

[0061] In this embodiment, after obtaining the vertex compression rates, the embodiment of the application can determine a gradient field in the parameter domain plane according to the vertex compression rates to obtain an isogram, and the specific process is as follows: first, all point lines and surfaces in N are traversed to establish an adjacency table, then the maximum value r_max and the minimum value r_min of the vertex compression rates are searched and stored in the adjacency table, then a point A corresponding to the minimum value r_min is set, a point B with the minimum metric around the point A is searched, and a normalized vector and an advancing direction are determined based on the point A and the point B.

[0062] Specifically, the method for determining the current advancing direction based on the current starting point and the current to-be-processed vertex can comprise the following steps: constructing an adjacency list based on each grid vertex in the parameter domain plane, the corresponding vertex compression rate and the associated information, and setting the vertex with the minimum vertex compression rate among each grid vertex as the current vertex; setting the vertex with the maximum vertex compression rate among each grid vertex as the to-be-compared vertex; determining each adjacent vertex adjacent to the current vertex based on the adjacency list, and determining the corresponding adjacent compression rate of each adjacent vertex; setting the vertex corresponding to the minimum adjacent compression rate among each adjacent compression rate as the current to-be-processed vertex; and determining 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 to-be-processed vertex in the parameter domain plane.

[0063] In step S13, each to-be-processed discrete point with the same compression rate as the current compression rate is determined in the parameter domain plane based on the current compression rate of the current to-be-processed vertex and the current coordinate information, and the current contour is determined based on each to-be-processed discrete point and the current advancing direction, and then it is judged whether the current compression rate is greater than the compression rate threshold corresponding to the to-be-compared vertex. If not, the current to-be-processed vertex is set as the current starting point, and the step of determining the current to-be-processed vertex is re-executed until the current compression rate is greater than the compression rate threshold.

[0064] In this embodiment, after the current advancing direction and the current advancing direction vector are obtained, the vertex compression rate corresponding to point B is obtained, and the first contour composed of discrete points is generated according to the point-line-surface interpolation algorithm. Specifically, the method for determining the current to-be-processed discrete point and the current contour based on the current compression rate of the current to-be-processed vertex and the current coordinate information in the parameter domain plane can comprise the following steps: determining the current compression rate corresponding to the current to-be-processed vertex and the current coordinate information based on the preset grid size and the current advancing direction vector, and determining each to-be-processed discrete point with the same compression rate as the current compression rate in the parameter domain plane, and then determining the discrete point coordinate information corresponding to each to-be-processed discrete point; determining 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 performing contour generation operation on each to-be-processed discrete point based on the gradient value and the discrete point coordinate information corresponding to each to-be-processed discrete point, to obtain the current contour.

[0065] Further, the process of generating the next contour is as follows: set ratio as the current compression ratio, then judge whether ratio is less than r_max, if less, calculate the size of point B, and according to the advancing direction Calculate the next point C of the advancing, then calculate the gradient value of point C to extract the next contour, it is worth mentioning that the embodiment of the application needs to use Laplace to smooth the contour until the loop is stopped, then process the boundary separately, and store the boundary line into the preset contour set. Specifically, the step of judging whether the current compression ratio is greater than the compression ratio threshold corresponding to the to-be-compared vertex, if not greater, setting the current to-be-processed vertex as the current starting point, and jumping back to the step of determining the current to-be-processed vertex, until the current compression ratio is greater than the compression ratio threshold, can include: determining the compression ratio threshold corresponding to the to-be-compared vertex, then judging 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 to-be-processed vertex as the current starting point, and jumping back to the step of determining the current to-be-processed vertex 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; using a preset Laplace smoothing processing algorithm to smooth the obtained contours to obtain corresponding smoothed contours respectively, and using a preset automatic adaptive curvature change algorithm to adjust the contour density of each smoothed contour to obtain each target contour, then storing each target contour into a preset contour hierarchy set in the order of generation; wherein the earlier the target contour is generated, the smaller the hierarchy number corresponding to the target contour is.

[0066] Step S14, vertically project each discrete point on each contour to the adjacent outer contour to obtain a projection point, and generate a mesh based on the distance ratio between each discrete point and the corresponding projection point to obtain a curved quadrilateral mesh corresponding to the aircraft.

[0067] In this embodiment, after obtaining each contour line, the embodiment of the application needs to fill the grid layer by layer according to the discrete points and the normal projection points. Specifically, each discrete point on each contour line is vertically projected to the adjacent outer contour line according to the generation order of each contour line to obtain a projection point, and a distance ratio between each discrete point and the corresponding projection point is used for grid generation to obtain a curved quadrilateral dominant grid corresponding to the aircraft, which can include: sequentially vertically projecting each discrete point on each target contour line in the preset contour level set to the adjacent outer contour line according to the order from small to large level to obtain an initial projection point corresponding to each discrete point; matching the discrete points and the corresponding initial projection points to obtain a matching result, determining a projection point size based on the matching result, and re-projecting the discrete points to the adjacent outer contour line based on the projection point size to obtain a target projection point; determining the adjacent discrete points of the discrete point on the target contour line and the adjacent projection points of the target projection point on the outer contour line to determine 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; determining a distance ratio based on the first distance and the second distance, and determining a grid filling rule based on the distance ratio to perform grid filling based on the grid filling rule to obtain a curved quadrilateral dominant grid corresponding to the aircraft.

[0068] In this embodiment, the steps of filling the grid are as follows: first, get the first line l1 of the inner circle, and calculate the normal projection points of all discrete points on l1 on the next contour line l2, then match the two points, and re-distribute the points on l2 according to the matching result and size, then calculate the distance s2 of the two points in l2 and the distance s1 of the two points on l1 corresponding to s2.

[0069] In a specific embodiment, the embodiment of the application needs to determine the size between each preset threshold value, and determine the filling method of the grid based on the determination result, and the expression is as follows:

[0070] If( )

[0071] Fill a quadrilateral;

[0072] Else If( )

[0073] Fill a triangle and a quadrilateral;

[0074] Else If( )

[0075] Fill two triangles and a quadrilateral.

[0076] It is worth mentioning that if two ring sizes differ by more than one time, the embodiment of the application needs to add an isogram in the middle and fill in the triangle for transition, and finally use the Denaylay (Delaunay triangulation algorithm) triangular grid filling in the innermost area until each line degree is filled in, so as to complete the parameter domain quadrilateral dominant grid G.

[0077] It can be understood that in the process of generating the curved surface quadrilateral dominant grid, the embodiment of the application needs to map the grid inversely to the three-dimensional space based on the position of the grid point in the parameter domain grid N in the grid filling result, so as to automatically generate the curved surface quadrilateral dominant grid. Specifically, the distance ratio is determined based on the distance ratio to determine the grid filling rule, and the grid filling rule is used for grid filling to obtain the curved surface quadrilateral dominant grid corresponding to the aircraft, which can include: judging whether the distance ratio is less than a first preset threshold value, if the distance ratio is less than the first preset threshold value, performing a quadrilateral filling operation on the parameter domain plane to obtain a grid filling result; if the distance ratio is not less than the first preset threshold value, judging whether the distance ratio is less than a second preset threshold value, if the distance ratio is less than the second preset threshold value, performing a filling operation of one triangle and one quadrilateral on the parameter domain plane to obtain a grid filling result; if the distance ratio is not less than the second preset threshold value, judging whether the distance ratio is less than a third preset threshold value, if the distance ratio is less than the third preset threshold value, performing a filling operation of two triangles and one quadrilateral on the parameter domain plane to obtain a grid filling result; if the distance ratio is not less than the third preset threshold value, generating a new isogram at the midpoint position of the target isogram and the outer isogram by using a linear interpolation algorithm, and performing a quadrilateral filling operation between the target isogram and the new isogram, and then performing a triangular filling operation between the new isogram and the outer isogram to obtain a grid filling result; inversely mapping the grid filling result to the three-dimensional space based on the coordinate position of each grid vertex in the grid filling result in the parameter domain space to obtain the curved surface quadrilateral dominant grid corresponding to the aircraft; the topological relationship corresponding to the grid filling result and the curved surface quadrilateral dominant grid is consistent.

[0078] As can be seen, the application first needs to determine surface mesh generation parameters based on the CAD file of the aircraft, to 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 grid edge metric corresponding to each grid vertex of the surface unstructured mesh and the parameter domain plane, to determine the vertex compression rate based on each grid edge metric; determine the adjacency table based on each vertex compression rate, then determine the current starting point with the minimum vertex compression rate and the to-be-compared vertex with the maximum vertex compression rate in the adjacency table, and determine the current to-be-processed vertex with the minimum compression rate among each vertex adjacent to the current starting point in the adjacency table, then determine the current advancing direction based on the current starting point and the current to-be-processed vertex; determine each to-be-processed discrete point 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 to-be-processed vertex, and determine the current contour based on each to-be-processed discrete point and the current advancing direction, then judge whether the current compression rate is greater than the compression rate threshold corresponding to the to-be-compared vertex, if not, set the current to-be-processed vertex as the current starting point, and rejump to the step of determining the current to-be-processed vertex until the current compression rate is greater than the compression rate threshold; project each discrete point on each contour to the adjacent outer contour in the vertical direction according to the order in which each contour is generated to obtain a projection point, and generate a mesh based on the distance ratio between each discrete point and the corresponding projection point to obtain a curved surface quadrilateral dominant mesh corresponding to the aircraft. In this way, the efficiency of generating the curved surface quadrilateral dominant mesh of the aircraft is improved in the process of generating the curved surface quadrilateral dominant mesh of the aircraft, thereby improving the user experience.

[0079] Correspondingly, referring to Figure 2 The application further provides a curved surface quadrilateral dominant mesh generation device of an aircraft, comprising:

[0080] A mesh generation parameter determination module 11 is configured to determine surface mesh generation parameters based on the CAD file of the aircraft, to 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 grid edge metric corresponding to each grid vertex of the surface unstructured mesh and the parameter domain plane, to determine the vertex compression rate based on each grid edge metric;

[0081] An adjacency table determination module 12 is configured to determine an adjacency table based on each vertex compression rate, then determine the current starting point with the minimum vertex compression rate and the to-be-compared vertex with the maximum vertex compression rate in the adjacency table, and determine the current to-be-processed vertex with the minimum compression rate among each vertex adjacent to the current starting point in the adjacency table, then determine the current advancing direction based on the current starting point and the current to-be-processed vertex;

[0082] The discrete point determination module 13 is configured to determine each to-be-processed discrete point with the same compression rate as the current compression rate based on the current compression rate of the current to-be-processed vertex and the current coordinate information in the parameter domain plane, determine the current contour line based on each to-be-processed discrete point and the current advancing direction, and then determine whether the current compression rate is greater than the compression rate threshold corresponding to the to-be-compared vertex. If not, the current to-be-processed vertex is set as the current starting point, and the step of determining the current to-be-processed vertex is re-executed until the current compression rate is greater than the compression rate threshold.

[0083] The mesh generation module 14 is configured to project each discrete point on each contour line to a neighboring outer contour line in a vertical direction according to the sequence in which each contour line is generated, to obtain a projection point, and generate a mesh based on the distance ratio between each discrete point and the corresponding projection point, to obtain a curved quadrilateral mesh corresponding to the aircraft.

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

[0085] The unstructured mesh construction unit is configured to read a CAD file of the aircraft, determine surface mesh generation parameters including a preset global target size and a preset curvature adaptive angle based on the CAD file, and construct a surface unstructured mesh corresponding to the aircraft by using a preset mesh generation algorithm and based on the surface mesh generation parameters.

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

[0087] The parameter domain plane determination unit is configured to map each mesh vertex and an associated edge 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.

[0088] The vertex compression rate determination unit is configured to determine a first mesh edge metric corresponding to each mesh vertex of the surface unstructured mesh and a second mesh edge metric corresponding to each mesh vertex in the parameter domain plane, and determine a corresponding vertex compression rate based on the first mesh edge metric and the corresponding second mesh edge metric.

[0089] In some embodiments, the adjacency table determination module 12 can specifically include:

[0090] A current vertex determination unit is configured to construct an adjacency list based on each mesh vertex in the parameter domain plane, a corresponding vertex compression rate, and associated information, and set a vertex with the smallest vertex compression rate among each mesh vertex as a current vertex, and then set a vertex with the largest vertex compression rate among each mesh vertex as a vertex to be compared;

[0091] A current vertex to be processed determination unit is configured to determine each adjacent vertex adjacent to the current vertex based on the adjacency list, and determine a corresponding adjacent compression rate of each adjacent vertex, and then set a vertex corresponding to a compression rate with the smallest value among each adjacent compression rate as a current vertex to be processed.

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

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

[0094] A discrete point coordinate information determination unit is configured to determine a current compression rate and current coordinate information corresponding to the current vertex to be processed based on a preset mesh size and the current advancing direction vector, and determine each vertex to be processed discrete point with the same compression rate as the current compression rate in the parameter domain plane, and then determine discrete point coordinate information corresponding to each vertex to be processed discrete point.

[0095] A current contour determination unit is configured to determine a corresponding gradient value based on the current advancing direction and the current coordinate information by using a preset point-line-surface interpolation algorithm, and perform a contour generation operation on each vertex to be processed discrete point based on the gradient value and the discrete point coordinate information corresponding to each vertex to be processed discrete point, to obtain a current contour.

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

[0097] A current starting point updating unit is configured to determine a 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 a current starting point, and then jump back to the step of determining a current vertex to be processed with the smallest compression rate among each vertex adjacent to the current starting point in the adjacency list, until the current compression rate is greater than the compression rate threshold value.

[0098] The target contour generating unit is configured to perform smoothing processing on each contour obtained by using a preset Laplace smoothing processing algorithm to obtain corresponding smoothed contours, adjust the contour density of each smoothed contour by using a preset automatic adaptive curved surface curvature change algorithm, obtain each target contour, and sequentially store each target contour in a preset contour level set according to the generation order.

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

[0100] The initial projection point generating unit is configured to sequentially perform vertical projection operation on each discrete point on each target contour in the preset contour level set to an adjacent outer contour in order of level from small to large, to obtain an initial projection point corresponding to each discrete point.

[0101] The target projection point generating unit is configured to match the discrete point with the corresponding initial projection point to obtain a matching result, determine a projection point size based on the matching result, perform vertical projection operation on the discrete point to the adjacent outer contour based on the projection point size to obtain a target projection point.

[0102] The distance determining unit is configured to determine a neighboring discrete point of the discrete point on the target contour and a neighboring projection point of the target projection point on the outer contour, to determine a first distance between the discrete point and the neighboring discrete point and a second distance between the target projection point and the neighboring projection point.

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

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

[0105] The first mesh filling result determining unit is configured to determine whether the distance ratio is less than a first preset threshold, and if the distance ratio is less than the first preset threshold, perform quadrilateral filling operation on the parameter domain plane to obtain a mesh filling result.

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

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

[0108] The fourth mesh filling result determination unit is configured to generate a new contour line at a midpoint position between the target contour line and the outer contour line by using a linear interpolation algorithm if the distance ratio is not less than the third preset threshold, and to perform a filling operation of a quadrangle between the target contour line and the new contour line and a filling operation of a triangle between the new contour line and the outer contour line to obtain a mesh filling result.

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

[0110] Further, the embodiment of the present application further discloses an electronic device, Figure 3 The electronic device 20 shown in the figure is not considered as any limitation on the use range of the present application. The electronic device 20 can specifically 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 is used to store a computer program, and the processor 21 loads and executes the computer program to implement the related steps in the curved quadrilateral-dominant mesh generation method of the aircraft disclosed in any of the preceding embodiments. In addition, the electronic device 20 in the embodiment can be an electronic computer.

[0111] In this embodiment, the power supply 23 is configured to provide operating voltage for each hardware device on the electronic device 20; the communication interface 24 is configured to create a data transmission channel between the electronic device 20 and external devices, and the communication protocol followed by the communication interface 24 can be any communication protocol applicable to the technical solution of the present application, which will not be specifically limited herein; the input and output interface 25 is configured to obtain external input data or output data to the outside, and the specific interface type can be selected according to the specific application requirements, which will not be specifically limited herein.

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

[0113] The operating system 221 is configured to manage and control each hardware device on the electronic device 20 and the computer program 222, and can be Windows Server, Netware, Unix, Linux, etc. In addition to the computer program capable of completing the aircraft curved quadrilateral dominant grid generation method disclosed in any of the preceding embodiments and executed by the electronic device 20, the computer program 222 can further include a computer program capable of completing other specific work.

[0114] Further, the present application also discloses a computer readable storage medium for storing a computer program; wherein the computer program is executed by a processor to implement the aircraft curved quadrilateral dominant grid generation method disclosed in the preceding embodiments. For the specific steps of the method, please refer to the corresponding contents disclosed in the preceding embodiments, which will not be described here.

[0115] Each embodiment in the specification is described in a progressive manner, and each embodiment focuses on the difference from other embodiments. For the same or similar parts between each embodiment, please refer to each other. For the device disclosed in the embodiments, since it corresponds to the method disclosed in the embodiments, the description is relatively simple, and please refer to the method part for the relevant part.

[0116] The skilled person can further realize that the units and algorithm steps of each example described in combination with the embodiments disclosed herein can be realized by electronic hardware, computer software or a combination of both. In order to clearly show the interchangeability of hardware and software, the components and steps of each example have been described in the above description. Whether the functions are realized in hardware or software depends on the specific application and design constraints of the technical solution. The skilled person can use different methods to realize the described functions for each specific application, but such implementation should not be considered beyond the scope of the present application.

[0117] The steps of a method or algorithm described in connection with the embodiments disclosed herein can be embodied directly in hardware, in a software module executed by a processor, or in a combination of the two. A software module can reside in RAM, flash memory, ROM, electrically programmable ROM (EPROM), electrically erasable programmable ROM (EEPROM), registers, hard disk, a removable disk, a CD-ROM, or any other form of storage medium known in the art. The

[0118] Finally, it should be noted that the terms "first", "second", and the like, herein do not denote any order, quantity, combination, or importance, but rather are used to distinguish one element from another, and do not imply or require any such actual relationship or order. Also, the terms "comprises", "comprising", or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but can include other elements not expressly listed or inherent to such process, method, article, or apparatus. Without further limitation, an element preceded by "comprises... a" does not, without more constraints, foreclose the existence of additional identical elements in the process, method, article, or apparatus that comprises the recited element.

[0119] The above detailed description of the technical solutions provided by the present application has been described in detail, and the principles and implementation modes of the present application have been described by applying specific examples; the above description of the embodiments is only for the purpose of helping to understand the method of the present application and its core idea; at the same time, for those skilled in the art, according to the idea of the present application, the specific implementation mode and application range will be changed; in view of the above, the content of the specification should not be understood as a limitation of the present 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 the contours 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, Determining an adjacency list based on the compression rates of the vertices, then determining a current starting point with the smallest vertex compression rate and a vertex to be compared with the largest vertex compression rate in the adjacency list, determining a current vertex to be processed with the smallest compression rate among vertices adjacent to the current starting point in the adjacency list, and then determining a current advancement direction based on the current starting point and the current vertex to be processed, includes: constructing an adjacency list based on each mesh vertex in the parameter domain plane, the corresponding vertex compression rate, and the associated information, and setting the vertex with the smallest vertex compression rate among the mesh vertices as the current vertex, and then setting the vertex with the largest vertex compression rate among the mesh vertices as the vertex to be compared; Determining adjacent vertices adjacent to the current vertex based on the adjacency list, and determining adjacent compression rates corresponding to the adjacent vertices, and then setting the vertex corresponding to the smallest compression rate among the adjacent compression rates as the current vertex to be processed; 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.

4. The method of claim 3, wherein, The method of determining discrete points to be processed having the same compression rate as the current compression rate in the parameter domain plane based on the current compression rate and current coordinate information of the current vertex to be processed, and determining a current contour line based on each discrete point to be processed and the current advancing direction, includes: Determining the current compression rate and current coordinate information corresponding to the current vertex to be processed based on the preset grid size and the current advancing direction vector, and determining each discrete point to be processed having the same compression rate as the current compression rate in the parameter domain plane, and then determining the discrete point coordinate information corresponding to each discrete point to be processed; The preset point-line-surface interpolation algorithm is used to determine the corresponding gradient value based on the current advancement direction and the current coordinate information, and the contour line generation operation is performed 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 to obtain the current contour line.

5. The method of claim 1, wherein, 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 not, setting the current vertex to be processed as the current starting point, and re-jumping to the step of determining the current vertex to be processed until the current compression ratio is greater than the compression ratio threshold, includes: Determining a compression rate threshold corresponding to the vertex to be compared, and then determining whether a current compression rate is greater than the compression rate threshold; if the current compression rate is not greater than the compression rate threshold, setting the current vertex to be processed as the current starting point, and re-jumping to the step of determining the current vertex to be processed with the smallest compression rate among the vertices adjacent to the current starting point in the adjacency table, until the current compression rate is greater than the compression rate threshold; 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 quadrilateral-dominated grid on a curved surface of 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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