CN118015223B - Method and device for generating three-manifold hexahedral grid - Google Patents
Method and device for generating three-manifold hexahedral grid Download PDFInfo
- Publication number
- CN118015223B CN118015223B CN202410421282.6A CN202410421282A CN118015223B CN 118015223 B CN118015223 B CN 118015223B CN 202410421282 A CN202410421282 A CN 202410421282A CN 118015223 B CN118015223 B CN 118015223B
- Authority
- CN
- China
- Prior art keywords
- grid
- mesh
- tetrahedral
- points
- hexahedral
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
- 238000000034 method Methods 0.000 title claims abstract description 64
- 230000006835 compression Effects 0.000 claims abstract description 44
- 238000007906 compression Methods 0.000 claims abstract description 44
- 238000013507 mapping Methods 0.000 claims abstract description 24
- 238000004364 calculation method Methods 0.000 claims abstract description 17
- 238000005259 measurement Methods 0.000 claims description 19
- 238000004422 calculation algorithm Methods 0.000 claims description 17
- 238000012545 processing Methods 0.000 claims description 9
- 238000009499 grossing Methods 0.000 claims description 7
- 230000008859 change Effects 0.000 abstract description 11
- 238000011161 development Methods 0.000 abstract description 6
- 230000009286 beneficial effect Effects 0.000 abstract description 4
- 238000004904 shortening Methods 0.000 abstract description 4
- 230000008569 process Effects 0.000 description 16
- 238000010586 diagram Methods 0.000 description 12
- 238000005192 partition Methods 0.000 description 8
- 238000003860 storage Methods 0.000 description 8
- 238000004590 computer program Methods 0.000 description 5
- 230000007246 mechanism Effects 0.000 description 4
- 238000000638 solvent extraction Methods 0.000 description 4
- 238000005516 engineering process Methods 0.000 description 3
- 238000006243 chemical reaction Methods 0.000 description 2
- 238000004891 communication Methods 0.000 description 2
- 238000000354 decomposition reaction Methods 0.000 description 2
- 239000012530 fluid Substances 0.000 description 2
- 238000013139 quantization Methods 0.000 description 2
- 230000003044 adaptive effect Effects 0.000 description 1
- 230000001413 cellular effect Effects 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 230000006870 function Effects 0.000 description 1
- 230000008676 import Effects 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 230000003287 optical effect Effects 0.000 description 1
- 239000004984 smart glass Substances 0.000 description 1
- 210000000689 upper leg Anatomy 0.000 description 1
- 239000013598 vector Substances 0.000 description 1
Classifications
-
- G—PHYSICS
- G06—COMPUTING; CALCULATING OR COUNTING
- G06T—IMAGE DATA PROCESSING OR GENERATION, IN GENERAL
- G06T17/00—Three dimensional [3D] modelling, e.g. data description of 3D objects
- G06T17/20—Finite element generation, e.g. wire-frame surface description, tesselation
-
- G—PHYSICS
- G06—COMPUTING; CALCULATING OR COUNTING
- G06F—ELECTRIC DIGITAL DATA PROCESSING
- G06F30/00—Computer-aided design [CAD]
- G06F30/20—Design optimisation, verification or simulation
- G06F30/28—Design optimisation, verification or simulation using fluid dynamics, e.g. using Navier-Stokes equations or computational fluid dynamics [CFD]
Landscapes
- Physics & Mathematics (AREA)
- Engineering & Computer Science (AREA)
- Computer Graphics (AREA)
- Geometry (AREA)
- Software Systems (AREA)
- General Physics & Mathematics (AREA)
- Theoretical Computer Science (AREA)
- Image Generation (AREA)
Abstract
The application provides a method and a device for generating a three-flow hexahedral mesh, wherein the method for generating the three-flow hexahedral mesh comprises the following steps: creating a three-flow tetrahedral grid of the object model; obtaining a sphere tetrahedral mesh based on the three-flow tetrahedral mesh; sequentially calculating the average volume of adjacent tetrahedrons of each grid point in the tri-manifold tetrahedron grid, and sequentially calculating the average volume of adjacent tetrahedrons of each grid point in the sphere tetrahedron grid; calculating a volume compression ratio according to the average volume of adjacent tetrahedrons of each grid point in the three-flow tetrahedron grid and the sphere tetrahedron grid, dividing the sphere tetrahedron grid according to the volume compression ratio, obtaining a hexahedral grid according to a division result, inversely mapping the hexahedral grid to the three-flow shape to obtain the target three-flow hexahedral grid, realizing automatic division of the three-flow structure grid adapting to any complex shape without excessive complex calculation and considering direction change, being beneficial to shortening the grid generation period and improving the development efficiency.
Description
Technical Field
The application relates to the technical field of computer graphics processing, in particular to a method for generating a three-flow hexahedral grid. The application also relates to a three-flow hexahedral mesh generating device, a computing device and a computer readable storage medium.
Background
With the development of computer technology, the use of structural grids in work and production is becoming more common, and structural grid automation is a complex project, which is derived from its own standardized structure. In the prior art, the earlier developed medial axis method calculates the medial axis reflecting the geometric shape characteristics through a geometric method, then provides a two-dimensional region decomposition based on a standard frame field, calculates flow lines of singular points in the staggered and standard frame fields by using the mapping relation between vectors and standard frames, and finally obtains a smooth standard frame field for region decomposition. For complex models, more characteristic constraints and the problems that a frame is hard to characterize are required to be considered, and the partition is difficult to apply in a three-dimensional space; a volume parameterization method based on harmonic energy is newly developed, and a three-variable B spline modeling model partition is created on parameterization, so that the method is only suitable for simple models such as femur and the like.
In order to apply the complex model, a partitioning technology is introduced for a mapping method, however, the existing standard frame field partitioning technology needs to consider more characteristic constraints, the standard frame is hard to characterize and the like, and is not enough to be used in three dimensions; the existing volume parameterization method based on the harmonic energy can only be applied to part of simple models, and has low generation efficiency. These methods do not guarantee the automatic generation of a structural mesh under any tri-manifold tetrahedral mesh.
Disclosure of Invention
In view of this, the embodiment of the application provides a method for generating a three-shaped hexahedral mesh, so as to solve the technical defects existing in the prior art. The embodiment of the application also provides a three-flow hexahedral grid generating device, a computing device and a computer readable storage medium.
According to a first aspect of an embodiment of the present application, there is provided a method for generating a three-dimensional hexahedral mesh, including:
creating a three-flow tetrahedral grid of the acquired object model;
the measurement of the three-flow tetrahedron grid is adjusted based on a preset algorithm, and a sphere tetrahedron grid is obtained, wherein the three-flow tetrahedron grid corresponds to grid points contained in the sphere tetrahedron grid one by one;
sequentially calculating grid points in the three-stream tetrahedron grid Average volume of adjacent tetrahedraAnd sequentially calculating grid points/>, in the spheroid tetrahedral meshAverage volume of adjacent tetrahedra；
According to the describedAnd saidCalculate the volumetric compression ratioAnd according to the volume compression ratioDividing the sphere tetrahedron grid to obtain at least one topological area;
And sequentially assembling the hexahedral mesh blocks of the at least one topological area to obtain a hexahedral mesh, and inversely mapping the hexahedral mesh to a three-manifold to obtain the target three-manifold hexahedral mesh.
Optionally, the computing sequentially calculates grid points in the tri-shaped tetrahedral meshAverage volume of adjacent tetrahedronsComprising:
Determining grid points contained in the tri-shaped tetrahedral grid ；
Sequentially inquiring the grid points in the tri-flow tetrahedron gridAdjacent tetrahedrons, the grid points/>, are calculatedAdjacent tetrahedral volume sum；
Calculating grid points in the tri-shaped tetrahedral meshAverage volume of adjacent tetrahedraWherein m is the grid pointThe number of adjacent tetrahedra in the tri-shaped tetrahedral mesh.
Optionally, the sequentially computing grid points in the spheroid tetrahedral meshAverage volume of adjacent tetrahedronsComprising:
Querying the corresponding relation of grid points between the spheroid tetrahedral grids and the tri-manifold tetrahedral grids, and determining the grid points contained in the spheroid tetrahedral grids based on the query result ；
Sequentially inquiring in the tetrahedron grid of the sphere and the grid pointAdjacent tetrahedrons, the grid points/>, are calculatedAdjacent tetrahedral volume sum；
Calculating grid points in the spheroid tetrahedral meshAverage volume of adjacent tetrahedraWherein n is the grid pointThe number of adjacent tetrahedrons in the spheroid tetrahedral mesh.
Optionally, said step of providing a base according to saidAnd saidCalculate the volumetric compression ratioComprising:
determining grid points in the spheroid tetrahedral mesh Maximum in average volume of adjacent tetrahedrons；
And according to theTheAnd saidCalculating the volumetric compression ratio。
Optionally, the volume compression ratio is based onDividing the sphere tetrahedral mesh to obtain at least one topological area, wherein the method comprises the following steps:
According to the volume compression ratio And corresponding grid points/>, in the spheroid tetrahedral meshEstablishing a grid cloud picture;
Extracting an isosurface according to the grid cloud image;
And carrying out smoothing and sharpening treatment on the isosurface in the grid cloud picture through a preset image processing algorithm to obtain the at least one topological area.
Optionally, the creating the three-manifold tetrahedral mesh of the acquired object model includes:
Setting surface grid generation parameters of the target object model;
Generating a surface unstructured grid according to the surface grid generation parameters and the target object model;
Setting a volume generation parameter of the surface non-mechanism grid, and generating the tri-flow tetrahedral grid according to the volume generation parameter and the surface non-structure grid.
Optionally, the adjusting the metric of the tri-shaped tetrahedral mesh based on a preset algorithm to obtain a spheroid tetrahedral mesh includes:
determining points contained within the tri-shaped tetrahedral mesh And determining boundary points/>, of the tri-shaped tetrahedral mesh；
The saidSetting the gaussian curvature of (2) to 0, and setting theIs set toObtaining three-stream tetrahedral mesh data, whereinB is the boundary point/>, of the three-flow tetrahedral meshIs the number of (3);
and calculating the measurement of the data of the three-flow tetrahedral mesh through a discrete Ricci curvature flow equation, and determining the mesh point coordinates of the spherical tetrahedral mesh according to the calculation result to obtain the spherical tetrahedral mesh.
Optionally, the sequentially assembling the hexahedral mesh blocks on the at least one topological area, to obtain a hexahedral mesh includes:
Determining grid points contained in the spheroid tetrahedral mesh And in the spheroid tetrahedral mesh with the mesh pointsConnected grid edges;
Calculating the average value of the lengths of the grid edges, and adjusting the edge length parameters of the grid edges according to the average value;
And sequentially assembling hexahedral grid blocks in the at least one topological area according to the side length parameters of the grid sides to obtain the hexahedral grid.
Optionally, the inversely mapping the hexahedral mesh to a three-manifold, and obtaining the target three-manifold hexahedral mesh includes:
Querying grid points contained in the spheroid tetrahedral mesh Grid point coordinates of (a);
determining the corresponding relation of grid points between the sphere tetrahedral grid and the hexahedral grid;
And projecting the hexahedral mesh to a tri-manifold based on the corresponding relation and the grid point coordinates to obtain the target tri-manifold hexahedral mesh.
According to a second aspect of an embodiment of the present application, there is provided a three-shaped hexahedral mesh generating device including:
A grid creation module configured to create a tri-manifold tetrahedral grid of the acquired object model;
the measurement adjustment module is configured to adjust the measurement of the three-flow tetrahedron grid based on a preset algorithm to obtain a sphere tetrahedron grid, wherein the three-flow tetrahedron grid corresponds to grid points contained in the sphere tetrahedron grid one by one;
a volume calculation module configured to sequentially calculate grid points in the tri-shaped tetrahedral mesh Average volume of adjacent tetrahedraAnd sequentially calculating grid points/>, in the spheroid tetrahedral meshAverage volume of adjacent tetrahedrons；
A region dividing module configured to, according to theAnd saidCalculate the volumetric compression ratioAnd according to the volume compression ratioDividing the sphere tetrahedron grid to obtain at least one topological area;
and the grid inverse mapping module is configured to sequentially assemble the hexahedral grid blocks of the at least one topological area to obtain a hexahedral grid, and inversely map the hexahedral grid to a three-flow shape to obtain the target three-flow-shaped hexahedral grid.
According to a third aspect of embodiments of the present application, there is provided a computing device comprising:
a memory and a processor;
The memory is used for storing computer executable instructions, and the processor realizes the steps of the three-fluid hexahedral grid generating method when executing the computer executable instructions.
According to a fourth aspect of embodiments of the present application, there is provided a computer-readable storage medium storing computer-executable instructions which, when executed by a processor, implement the steps of the method of generating a three-manifold hexahedral mesh.
According to a fifth aspect of embodiments of the present application, there is provided a chip storing a computer program which, when executed by the chip, implements the steps of the three-shaped hexahedral mesh generating method.
According to the three-flow-shaped hexahedral mesh generation method provided by the application, the three-flow-shaped tetrahedral mesh of the obtained object model is created;
the measurement of the three-flow tetrahedron grid is adjusted based on a preset algorithm, and a sphere tetrahedron grid is obtained, wherein the three-flow tetrahedron grid corresponds to grid points contained in the sphere tetrahedron grid one by one;
sequentially calculating grid points in the three-stream tetrahedron grid Average volume of adjacent tetrahedraAnd sequentially calculating grid points/>, in the spheroid tetrahedral meshAverage volume of adjacent tetrahedra；
According to the describedAnd saidCalculate the volumetric compression ratioAnd according to the volume compression ratioDividing the sphere tetrahedron grid to obtain at least one topological area;
and sequentially assembling the hexahedral mesh blocks of the at least one topological area to obtain hexahedral mesh, and inversely mapping the hexahedral mesh to the three-manifold to obtain the target three-manifold hexahedral mesh, so that the three-manifold structure mesh adapting to any complex shape is automatically divided without excessive complex calculation and without considering direction change, thereby being beneficial to shortening the mesh generation period and improving the development efficiency.
Drawings
In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required for the description of the embodiments will be briefly described below, and it is apparent that the drawings in the following description are only some embodiments of the present application, and other drawings may be obtained according to these drawings without inventive effort for a person skilled in the art.
FIG. 1 is a flowchart of a method for generating a three-dimensional hexahedral mesh according to an embodiment of the present application;
FIG. 2 is a schematic diagram of a method for generating a three-dimensional hexahedral mesh according to an embodiment of the present application;
FIG. 3 is a process flow diagram of a method for generating a tri-shaped hexahedral mesh for a gear workpiece according to one embodiment of the present application;
fig. 4 is a schematic structural view of a three-shaped hexahedral mesh generating device according to an embodiment of the present application;
FIG. 5 is a block diagram of a computing device according to one embodiment of the application.
Detailed Description
In the following description, numerous specific details are set forth in order to provide a thorough understanding of the present application. The present application may be embodied in many other forms than those herein described, and those skilled in the art will readily appreciate that the present application may be similarly embodied without departing from the spirit or essential characteristics thereof, and therefore the present application is not limited to the specific embodiments disclosed below.
The terminology used in the one or more embodiments of the application is for the purpose of describing particular embodiments only and is not intended to be limiting of the one or more embodiments of the application. As used in one or more embodiments of the application and the appended claims, the singular forms "a," "an," and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise. It should also be understood that the term "and/or" as used in one or more embodiments of the present application refers to and encompasses any or all possible combinations of one or more of the associated listed items.
It should be understood that, although the terms first, second, etc. may be used in one or more embodiments of the application to describe various information, these information should not be limited by these terms. These terms are only used to distinguish one type of information from another. For example, a first may also be referred to as a second, and similarly, a second may also be referred to as a first, without departing from the scope of one or more embodiments of the application.
First, terms related to one or more embodiments of the present invention will be explained.
Igs file: the file formats of 2D and 3D geometries are described, stored and exchanged by standard data interface specifications.
Iso-surface: a curved surface in space on which the value of the function F (x, y, z) is equal to a given value Ft, i.e. the isosurface is defined by all points s= { (x, y, z): f (x, y, z) =ft }.
CFD: computational fluid dynamics.
And (3) body parameterization: a three-variable tensor parameterized model is created to establish a one-to-one mapping relationship with a regular enclosure.
In the present application, a method of generating a three-shaped hexahedral mesh is provided. The present application relates to a three-dimensional hexahedral mesh generating device, a computing device, and a computer-readable storage medium, which are described in detail one by one in the following embodiments.
Fig. 1 shows a flowchart of a method for generating a three-dimensional hexahedral mesh according to an embodiment of the present application, which specifically includes the following steps:
S102: creating a three-flow tetrahedral grid of the acquired object model;
S104: the measurement of the three-flow tetrahedron grid is adjusted based on a preset algorithm, and a sphere tetrahedron grid is obtained, wherein the three-flow tetrahedron grid corresponds to grid points contained in the sphere tetrahedron grid one by one;
S106: sequentially calculating grid points in the three-stream tetrahedron grid Average volume of adjacent tetrahedraAnd sequentially calculating grid points/>, in the spheroid tetrahedral meshAverage volume of adjacent tetrahedra；
S108: according to the describedAnd saidCalculate the volumetric compression ratioAnd according to the volume compression ratioDividing the sphere tetrahedron grid to obtain at least one topological area;
S110: and sequentially assembling the hexahedral mesh blocks of the at least one topological area to obtain a hexahedral mesh, and inversely mapping the hexahedral mesh to a three-manifold to obtain the target three-manifold hexahedral mesh.
The object model is model data needed to construct a corresponding tri-manifold hexahedral mesh, which may be scan data obtained by a user scanning a workpiece, or a model made by a user using a modeling tool, where the kind and source of the object model are determined by an actual use scenario, and the embodiment is not limited. It should be noted that the three-flow shape is also called a three-dimensional manifold, i.e., a manifold in three-dimensional space.
Based on the method, corresponding three-shaped tetrahedral grids are generated according to the obtained object model, and the topology of the three-shaped tetrahedral grids is made to be a sphere tetrahedral grid through parameter adjustment related to the three-shaped tetrahedral grids. Determining corresponding grid points in the three-flow tetrahedron grids and the sphere tetrahedron grids before and after conversion, and tetrahedrons adjacent to the grid points, calculating the average volume of tetrahedrons connected with the grid points, changing the tetrahedron grids connected with the grid points from the three-flow tetrahedron grids to the sphere tetrahedron grids according to the change of the average volume of the tetrahedron grids, calculating the volume compression ratio before and after the change, dividing the sphere tetrahedron grids according to the calculated volume compression ratio value to obtain topology subareas, selecting the topology subareas for filling the hexahedron grids to obtain hexahedron grids, inversely mapping the obtained hexahedron grids to three-flow shapes, and obtaining the three-flow hexahedron grids of the target object model. The method has the advantages that excessive complex calculation is not needed, the direction change is not considered, the three-stream-shaped structural grids adapting to any complex shape are automatically divided, the grid generation period is shortened, and the development efficiency is improved.
Further, in the process of creating a three-manifold tetrahedral mesh of the object model, the specific implementation manner in this embodiment is as follows:
Setting surface grid generation parameters of the target object model; generating a surface unstructured grid according to the surface grid generation parameters and the target object model; setting a volume generation parameter of the surface non-mechanism grid, and generating the tri-flow tetrahedral grid according to the volume generation parameter and the surface non-structure grid.
The surface mesh generation parameters include parameters such as global target size, curvature self-adaptive angle, and the like, and specific parameter selection is determined by actual use scenes, which is not limited in this embodiment. The volume generation parameters include parameters such as mesh size and growth rate, and the specific parameters are determined by actual usage scenario, and the embodiment is not limited.
Based on this, as shown in the schematic diagram of a three-manifold hexahedral mesh generating method in fig. 2, the background mesh generation is a three-manifold tetrahedral mesh generating process of the object model, the object model is stored in the igs file, the surface non-structural mesh related to the object model is generated after the presentation form of the surface non-structural mesh is defined by setting the surface mesh generating parameters, then the set volume generating parameters are set again, and the inside of the surface non-structural mesh is filled with the tetrahedral mesh to obtain the three-manifold tetrahedral mesh of the object model.
Further, in the process of generating a corresponding spherical tetrahedral mesh by using the three-shaped tetrahedral mesh, the specific implementation manner is as follows:
determining points contained within the tri-shaped tetrahedral mesh And determining boundary points/>, of the tri-shaped tetrahedral mesh；
The saidSetting the gaussian curvature of (2) to 0, and setting theIs set toObtaining three-stream tetrahedral mesh data, whereinB is the boundary point/>, of the three-flow tetrahedral meshIs the number of (3);
and calculating the measurement of the data of the three-flow tetrahedral mesh through a discrete Ricci curvature flow equation, and determining the mesh point coordinates of the spherical tetrahedral mesh according to the calculation result to obtain the spherical tetrahedral mesh.
In the process of volume parameterization, as shown in the schematic diagram of a method for generating a three-dimensional hexahedral mesh in fig. 2, the three-dimensional tetrahedral mesh is converted into a spherical tetrahedral mesh by performing processing of setting target curvature, calculating target metric and calculating point coordinates of the mesh.
Specifically, the gaussian curvature of the boundary points of the three-flow tetrahedron grid is set to be 0, so that the boundary points are spherically distributed, and the three-flow tetrahedron grid can be changed into a sphere tetrahedron grid under the condition that the topological structure of the three-flow tetrahedron grid is not changed by correspondingly adjusting the gaussian curvature of the internal containing points of the three-flow tetrahedron grid. And then, calculating the measurement of the deformed three-flow tetrahedral mesh data through a discrete Ricci curvature flow equation, and determining the mesh point coordinates of the spherical tetrahedral mesh according to the calculation result to realize the conversion from the three-flow tetrahedral mesh to the spherical tetrahedral mesh.
Further, the average volume of tetrahedrons adjacent to the grid points in the tri-manifold tetrahedron mesh is calculated, and in this embodiment, the specific implementation manner is as follows:
Determining grid points contained in the tri-shaped tetrahedral grid ；
Sequentially inquiring the grid points in the tri-flow tetrahedron gridAdjacent tetrahedrons, the grid points/>, are calculatedAdjacent tetrahedral volume sum；
Calculating grid points in the tri-shaped tetrahedral meshAverage volume of adjacent tetrahedraWherein m is the grid pointThe number of adjacent tetrahedra in the tri-shaped tetrahedral mesh.
Further, the average volume of tetrahedrons adjacent to the grid points in the tetrahedron mesh of the sphere is calculated, and in this embodiment, the specific implementation manner is as follows:
Querying the corresponding relation of grid points between the spheroid tetrahedral grids and the tri-manifold tetrahedral grids, and determining the grid points contained in the spheroid tetrahedral grids based on the query result ；
Sequentially inquiring in the tetrahedron grid of the sphere and the grid pointAdjacent tetrahedrons, the grid points/>, are calculatedAdjacent tetrahedral volume sum；
Calculating grid points in the spheroid tetrahedral meshAverage volume of adjacent tetrahedraWherein n is the grid pointThe number of adjacent tetrahedrons in the spheroid tetrahedral mesh.
Further, in the process of calculating the volumetric compression ratio, in this embodiment, the specific implementation manner is as follows:
determining grid points in the spheroid tetrahedral mesh Maximum in average volume of adjacent tetrahedrons；
And according to theTheAnd saidCalculating the volumetric compression ratio。
As shown in the schematic diagram of one method for generating a three-manifold hexahedral mesh in fig. 2, the "M mesh points" are mesh points in the three-manifold tetrahedral mesh, and the "N mesh points" are mesh points in the spheroid tetrahedral mesh.
Specifically, the implementation process of "calculating the average volume at the M grid points" and "calculating the average volume at the N grid points" is that, in the three-manifold tetrahedron grid and the sphere tetrahedron grid, tetrahedrons adjacent to each grid point are determined, then the tetrahedron grid volumes adjacent to each grid point are added, and then the obtained sum of the volumes corresponding to each grid point is divided by the number of the tetrahedrons adjacent to each other, so that the average volume of the tetrahedrons adjacent to each grid point is calculated.
In addition, the implementation process of calculating the volume change compression ratio is that the corresponding relation of each grid point in the tri-manifold tetrahedron grid and the sphere tetrahedron grid is determined, the ratio of the average volumes of adjacent tetrahedrons of the corresponding grid points is calculated, and the obtained ratio of each grid point is divided by the maximum value of the average volumes of adjacent tetrahedrons of the grid points in the sphere tetrahedron grid, so that the volume compression ratio corresponding to the grid point can be obtained.
Further, in this embodiment, the specific implementation manner is as follows:
According to the volume compression ratio And corresponding grid points/>, in the spheroid tetrahedral meshEstablishing a grid cloud picture;
Extracting an isosurface according to the grid cloud image;
And carrying out smoothing and sharpening treatment on the isosurface in the grid cloud picture through a preset image processing algorithm to obtain the at least one topological area.
As shown in the schematic diagram of the three-flow hexahedral mesh generating method in fig. 2, the "volume change field" is a spheroid tetrahedral mesh, and then the implementation process of extracting an isosurface from the volume change field is specifically to make a cloud chart about the spheroid tetrahedral mesh according to the value of the volume compression ratio, and it should be noted that the isosurface can also be directly generated based on the value of the volume compression ratio according to the cloud chart, and the mode of extracting the isosurface is determined according to the actual use scenario, which is not limited in this embodiment. In addition, after the isosurface of the sphere tetrahedron grid is extracted, smoothing and sharpening are carried out on the isosurface, and a space topology partition is generated, so that at least one topology region is obtained.
Further, the process of assembling the hexahedral mesh blocks in the topology area is implemented as follows in this embodiment:
Determining grid points contained in the spheroid tetrahedral mesh And in the spheroid tetrahedral mesh with the mesh pointsConnected grid edges; calculating the average value of the length of the grid edge, and adjusting the edge length parameter of the grid edge according to the average value; and sequentially assembling hexahedral grid blocks in the at least one topological area according to the side length parameters of the grid sides to obtain the hexahedral grid.
In the process of "partition boundary quantization", as shown in the schematic diagram of a three-shaped hexahedral mesh generation method in fig. 2, the mesh sides connected with the mesh points in the four-sided mesh of the sphere need to be determined, and the average value of the mesh sides connected with the same mesh point is calculated, so that the mesh size of the mesh is determined, and quantization is completed. In addition, the process of filling the partition network by using the template method is to assemble hexahedral mesh blocks in the topological area according to the confirmed mesh size, so as to generate the hexahedral network.
Further, the process of inversely mapping the hexahedral mesh to the three-shape is implemented in this embodiment as follows:
Querying grid points contained in the spheroid tetrahedral mesh Grid point coordinates of (a); determining the corresponding relation of grid points between the sphere tetrahedral grid and the hexahedral grid; and projecting the hexahedral mesh to a tri-manifold based on the corresponding relation and the grid point coordinates to obtain the target tri-manifold hexahedral mesh.
As shown in a schematic diagram of a method for generating a three-stream hexahedral mesh in fig. 2, the implementation process of forming a space mesh by inverse mapping includes mapping mesh points of the hexahedral mesh to three-streams according to a positional relationship between the spherical tetrahedral mesh and each mesh point in the hexahedral mesh, and due to a mapping relationship between the spherical tetrahedral mesh and each mesh point in the three-stream tetrahedral mesh, the three-stream hexahedral mesh of the object model is obtained.
The method for generating the three-shaped hexahedral mesh provided by the application is taken as an example for gear workpieces, and is further described below with reference to fig. 3. Fig. 3 shows a process flow chart of a method for generating a tri-shaped hexahedral mesh applied to a gear workpiece according to an embodiment of the present application, which specifically includes the following steps:
s302: and setting surface grid generation parameters of the target object model.
S304: and generating a surface unstructured grid according to the surface grid generation parameters and the target object model.
Specifically, the user needs to create a tri-shaped hexahedral mesh about the gear workpiece a, first, the user imports a CAD digital-analog igs file of the workpiece a, and then sets global target size parameters and curvature adaptive angle parameters about the workpiece a model, so as to generate a surface unstructured mesh of the workpiece a model.
S306: setting a volume generation parameter of the surface non-mechanism grid, and generating a triple-manifold tetrahedral grid according to the volume generation parameter and the surface non-structure grid.
Specifically, a grid size parameter and a growth rate parameter are set, so that the tetrahedral grid fills the surface unstructured grid of the workpiece A to obtain a tri-shaped tetrahedral grid M of the workpiece A.
S308: and adjusting the measurement of the three-flow tetrahedral mesh based on a preset algorithm to obtain a sphere tetrahedral mesh.
Specifically, according to the measurement change of the three-manifold tetrahedral mesh M induced by the preset target Gaussian curvature, the Gaussian curvature of the internal points of the three-manifold tetrahedral mesh M is set to be 0, and the calculation formula of the target Gaussian curvature of the boundary points is as followsB is the number of boundary points of the three-flow tetrahedral mesh M. And calculating a target metric by using a discrete Ricci curvature flow equation, and calculating the point coordinates of the processed three-flow tetrahedral mesh M by using the induced metric to obtain a spherical tetrahedral mesh N.
S310: determining mesh points contained in a tri-manifold tetrahedral mesh。
S312: sequentially inquiring in a three-stream tetrahedron grid and the grid pointAdjacent tetrahedrons, computing grid pointsAdjacent tetrahedral volume sum。
S314: calculating grid points in a tri-manifold tetrahedral meshAverage volume of adjacent tetrahedra。
Wherein m is the grid pointThe number of adjacent tetrahedra in the tri-shaped tetrahedral mesh.
S316: sequentially calculating grid points in a spheroid tetrahedron gridAverage volume of adjacent tetrahedra。
S318: determining grid points in a spheroid tetrahedral meshMaximum in average volume of adjacent tetrahedrons。
S320: according to、AndCalculate the volumetric compression ratio。
Specifically, tetrahedrons adjacent to each grid point in the tri-manifold tetrahedron grid M are determined, the total volume of the tetrahedrons adjacent to each grid point is calculated, the total volume corresponding to each grid point is divided by the number of the tetrahedrons adjacent to each grid point, the average volume of the tetrahedrons adjacent to each grid point is obtained, and the average volumes of the tetrahedrons adjacent to each grid point are stored on the corresponding grid points. Determining tetrahedrons adjacent to each grid point in the tetrahedron grid N of the sphere, calculating the average volume of the tetrahedrons adjacent to each grid point of the tetrahedron grid N of the sphere in a similar manner, and storing the calculated average volume data on the grid points corresponding to the tetrahedron grid N of the sphere.
Determining the average volume maximum value of adjacent tetrahedrons of grid points in the spherical tetrahedron grid N, inquiring the tri-manifold tetrahedron grid M and the spherical tetrahedron grid N, determining the one-to-one correspondence relation of the grid points contained in the tri-manifold tetrahedron grid M and the spherical tetrahedron grid N, extracting the average volume data stored in the corresponding grid points, calculating the ratio between the average volume related to the spherical tetrahedron grid N and the average volume related to the tri-manifold tetrahedron grid M, dividing the ratio by the average volume maximum value of adjacent tetrahedrons of the grid points in the spherical tetrahedron grid N, obtaining the volume compression ratio corresponding to each grid point in the spherical tetrahedron grid N, and storing the volume compression ratio in the corresponding grid point.
S322: according to the volume compression ratioAnd corresponding grid points/>, in a spheroid tetrahedral gridAnd establishing a grid cloud picture.
S324: and extracting the isosurface according to the grid cloud image.
S326: and carrying out smoothing and sharpening treatment on the isosurface in the grid cloud picture through a preset image processing algorithm to obtain at least one topological area.
Specifically, a cloud picture is generated according to the volume compression ratio values stored in each grid point of the four-side grid N of the sphere, an isosurface is extracted according to the cloud picture, and the isosurface is smoothed and sharpened to obtain the topological partition of the four-side grid N of the sphere.
S328: and sequentially assembling the hexahedral mesh blocks of at least one topological area to obtain the hexahedral mesh.
S330: and inversely mapping the hexahedral mesh to the three-manifold to obtain the target three-manifold hexahedral mesh.
Specifically, all grid edges around each grid point of the four-side grid N of the sphere are queried, the grid sizes are weighted and averaged, the grid sizes are stored on the grid points, and in the obtained topological partition, grid block assembly is performed according to the grid sizes, so that a hexahedral grid S is generated. And inversely mapping the hexahedral mesh S to a three-manifold according to the position relation between the grid points in the hexahedral mesh S and the grid points in the spherical tetrahedral mesh N to obtain the three-manifold hexahedral mesh of the workpiece A.
In summary, by creating a three-manifold tetrahedral mesh of the acquired object model; adjusting the measurement of the three-flow tetrahedral mesh based on a preset algorithm to obtain a sphere tetrahedral mesh; sequentially calculating grid points in the three-stream tetrahedron gridAverage volume of adjacent tetrahedraAnd sequentially calculating grid points/>, in the spheroid tetrahedral meshAverage volume of adjacent tetrahedra; According to theAnd saidCalculate the volumetric compression ratioAnd according to the volume compression ratioDividing the sphere tetrahedron grid to obtain at least one topological area; and sequentially assembling the hexahedral mesh blocks of the at least one topological area to obtain hexahedral mesh, and inversely mapping the hexahedral mesh to the three-manifold to obtain the target three-manifold hexahedral mesh, so that the three-manifold structure mesh adapting to any complex shape is automatically divided without excessive complex calculation and without considering direction change, thereby being beneficial to shortening the mesh generation period and improving the development efficiency.
Corresponding to the method embodiment, the application also provides an embodiment of the three-dimensional hexahedral mesh generating device, and fig. 4 shows a schematic structural diagram of the three-dimensional hexahedral mesh generating device according to an embodiment of the application. As shown in fig. 4, the apparatus includes:
a mesh creation module 402 configured to create a tri-shaped tetrahedral mesh of the acquired object model;
The measurement adjustment module 404 is configured to adjust the measurement of the tri-manifold tetrahedral mesh based on a preset algorithm to obtain a sphere tetrahedral mesh, wherein the tri-manifold tetrahedral mesh corresponds to grid points contained in the sphere tetrahedral mesh one by one;
a volume calculation module 406 configured to sequentially calculate grid points in the tri-shaped tetrahedral mesh Average volume of adjacent tetrahedraAnd sequentially calculating grid points/>, in the spheroid tetrahedral meshAverage volume of adjacent tetrahedra；
A region dividing module 408 configured to, according to theAnd saidCalculate the volumetric compression ratioAnd according to the volume compression ratioDividing the sphere tetrahedron grid to obtain at least one topological area;
The grid inverse mapping module 410 is configured to sequentially perform hexahedral grid block assembly on the at least one topological area to obtain a hexahedral grid, and inversely map the hexahedral grid to a tri-manifold to obtain a target tri-manifold hexahedral grid.
In an alternative embodiment, the volume calculation module 406 is further configured to:
Determining grid points contained in the tri-shaped tetrahedral grid ；
Sequentially inquiring the grid points in the tri-flow tetrahedron gridAdjacent tetrahedrons, the grid points/>, are calculatedAdjacent tetrahedral volume sum；
Calculating grid points in the tri-shaped tetrahedral meshAverage volume of adjacent tetrahedraWherein m is the grid pointThe number of adjacent tetrahedra in the tri-shaped tetrahedral mesh.
In an alternative embodiment, the volume calculation module 406 is further configured to:
Querying the corresponding relation of grid points between the spheroid tetrahedral grids and the tri-manifold tetrahedral grids, and determining the grid points contained in the spheroid tetrahedral grids based on the query result ；
Sequentially inquiring in the tetrahedron grid of the sphere and the grid pointAdjacent tetrahedrons, the grid points/>, are calculatedAdjacent tetrahedral volume sum；
Calculating grid points in the spheroid tetrahedral meshAverage volume of adjacent tetrahedraWherein n is the grid pointThe number of adjacent tetrahedrons in the spheroid tetrahedral mesh.
In an alternative embodiment, the region partitioning module 408 is further configured to:
determining grid points in the spheroid tetrahedral mesh Maximum in average volume of adjacent tetrahedrons；
And according to theTheAnd saidCalculating the volume compression ratio。
In an alternative embodiment, the region partitioning module 408 is further configured to:
According to the volume compression ratio And corresponding grid points/>, in the spheroid tetrahedral meshEstablishing a grid cloud picture;
Extracting an isosurface according to the grid cloud image;
And carrying out smoothing and sharpening treatment on the isosurface in the grid cloud picture through a preset image processing algorithm to obtain the at least one topological area.
In an alternative embodiment, the grid creation module 402 is further configured to:
Setting surface grid generation parameters of the target object model; generating a surface unstructured grid according to the surface grid generation parameters and the target object model; setting a volume generation parameter of the surface non-mechanism grid, and generating the tri-flow tetrahedral grid according to the volume generation parameter and the surface non-structure grid.
In an alternative embodiment, the metric adjustment module 404 is further configured to:
determining points contained within the tri-shaped tetrahedral mesh And determining boundary points/>, of the tri-shaped tetrahedral mesh；
The saidSetting the gaussian curvature of (2) to 0, and setting theIs set toObtaining three-stream tetrahedral mesh data, whereinB is the boundary point/>, of the three-flow tetrahedral meshIs the number of (3);
and calculating the measurement of the data of the three-flow tetrahedral mesh through a discrete Ricci curvature flow equation, and determining the mesh point coordinates of the spherical tetrahedral mesh according to the calculation result to obtain the spherical tetrahedral mesh.
In an alternative embodiment, the grid inverse mapping module 410 is further configured to:
Determining grid points contained in the spheroid tetrahedral mesh And in the spheroid tetrahedral mesh with the mesh pointsConnected grid edges; calculating the average value of the length of the grid edge, and adjusting the edge length parameter of the grid edge according to the average value; and sequentially assembling hexahedral grid blocks in the at least one topological area according to the side length parameters of the grid sides to obtain the hexahedral grid.
In an alternative embodiment, the grid inverse mapping module 410 is further configured to:
Querying grid points contained in the spheroid tetrahedral mesh Grid point coordinates of (a); determining the corresponding relation of grid points between the sphere tetrahedral grid and the hexahedral grid; and projecting the hexahedral mesh to a tri-manifold based on the corresponding relation and the grid point coordinates to obtain the target tri-manifold hexahedral mesh.
The three-shaped hexahedral mesh generating device provided by the application is characterized in that three-shaped tetrahedral meshes of an acquired object model are created; adjusting the measurement of the three-flow tetrahedral mesh based on a preset algorithm to obtain a sphere tetrahedral mesh; sequentially calculating grid points in the three-stream tetrahedron gridAverage volume of adjacent tetrahedraAnd sequentially calculating grid points/>, in the spheroid tetrahedral meshAverage volume of adjacent tetrahedra; According to theAnd saidCalculate the volumetric compression ratioAnd according to the volume compression ratioDividing the sphere tetrahedron grid to obtain at least one topological area; and sequentially assembling the hexahedral mesh blocks of the at least one topological area to obtain hexahedral mesh, and inversely mapping the hexahedral mesh to the three-manifold to obtain the target three-manifold hexahedral mesh, so that the three-manifold structure mesh adapting to any complex shape is automatically divided without excessive complex calculation and without considering direction change, thereby being beneficial to shortening the mesh generation period and improving the development efficiency. /(I)
The above is a schematic scheme of a three-shaped hexahedral mesh generating device of the present embodiment. It should be noted that, the technical solution of the three-dimensional hexahedral mesh generating device and the technical solution of the three-dimensional hexahedral mesh generating method belong to the same conception, and details of the technical solution of the three-dimensional hexahedral mesh generating device, which are not described in detail, can be referred to the description of the technical solution of the three-dimensional hexahedral mesh generating method. Furthermore, the components in the apparatus embodiments should be understood as functional blocks that must be established to implement the steps of the program flow or the steps of the method, and the functional blocks are not actually functional partitions or separate limitations. The device claims defined by such a set of functional modules should be understood as a functional module architecture for implementing the solution primarily by means of the computer program described in the specification, and not as a physical device for implementing the solution primarily by means of hardware.
Fig. 5 illustrates a block diagram of a computing device 500, provided in accordance with an embodiment of the present application. The components of the computing device 500 include, but are not limited to, a memory 510 and a processor 520. Processor 520 is coupled to memory 510 via bus 530 and database 550 is used to hold data.
Computing device 500 also includes access device 540, access device 540 enabling computing device 500 to communicate via one or more networks 560. Examples of such networks include the Public Switched Telephone Network (PSTN), a Local Area Network (LAN), a Wide Area Network (WAN), a Personal Area Network (PAN), or a combination of communication networks such as the internet. The access device 540 may include one or more of any type of network interface, wired or wireless (e.g., a Network Interface Card (NIC)), such as an IEEE802.11 Wireless Local Area Network (WLAN) wireless interface, a worldwide interoperability for microwave access (Wi-MAX) interface, an ethernet interface, a Universal Serial Bus (USB) interface, a cellular network interface, a bluetooth interface, a Near Field Communication (NFC) interface, and so forth.
In one embodiment of the application, the above-described components of computing device 500, as well as other components not shown in FIG. 5, may also be connected to each other, such as by a bus. It should be understood that the block diagram of the computing device illustrated in FIG. 5 is for exemplary purposes only and is not intended to limit the scope of the present application. Those skilled in the art may add or replace other components as desired.
Computing device 500 may be any type of stationary or mobile computing device, including a mobile computer or mobile computing device (e.g., tablet, personal digital assistant, laptop, notebook, netbook, etc.), mobile phone (e.g., smart phone), wearable computing device (e.g., smart watch, smart glasses, etc.), or other type of mobile device, or a stationary computing device such as a desktop computer or PC. Computing device 500 may also be a mobile or stationary server.
Wherein the processor 520 is configured to execute the following computer-executable instructions:
creating a three-flow tetrahedral grid of the acquired object model;
the measurement of the three-flow tetrahedron grid is adjusted based on a preset algorithm, and a sphere tetrahedron grid is obtained, wherein the three-flow tetrahedron grid corresponds to grid points contained in the sphere tetrahedron grid one by one;
sequentially calculating grid points in the three-stream tetrahedron grid Average volume of adjacent tetrahedraAnd sequentially calculating grid points/>, in the spheroid tetrahedral meshAverage volume of adjacent tetrahedra；
According to the describedAnd saidCalculate the volumetric compression ratioAnd according to the volume compression ratioDividing the sphere tetrahedron grid to obtain at least one topological area;
And sequentially assembling the hexahedral mesh blocks of the at least one topological area to obtain a hexahedral mesh, and inversely mapping the hexahedral mesh to a three-manifold to obtain the target three-manifold hexahedral mesh.
The foregoing is a schematic illustration of a computing device of this embodiment. It should be noted that, the technical solution of the computing device and the technical solution of the three-dimensional hexahedral mesh generating method belong to the same concept, and details of the technical solution of the computing device, which are not described in detail, can be referred to the description of the technical solution of the three-dimensional hexahedral mesh generating method.
An embodiment of the present application also provides a computer-readable storage medium storing computer instructions that, when executed by a processor, are configured to:
creating a three-flow tetrahedral grid of the acquired object model;
the measurement of the three-flow tetrahedron grid is adjusted based on a preset algorithm, and a sphere tetrahedron grid is obtained, wherein the three-flow tetrahedron grid corresponds to grid points contained in the sphere tetrahedron grid one by one;
sequentially calculating grid points in the three-stream tetrahedron grid Average volume of adjacent tetrahedraAnd sequentially calculating grid points/>, in the spheroid tetrahedral meshAverage volume of adjacent tetrahedra；
According to the describedAnd saidCalculate the volumetric compression ratioAnd according to the volume compression ratioDividing the sphere tetrahedron grid to obtain at least one topological area;
And sequentially assembling the hexahedral mesh blocks of the at least one topological area to obtain a hexahedral mesh, and inversely mapping the hexahedral mesh to a three-manifold to obtain the target three-manifold hexahedral mesh.
The above is an exemplary version of a computer-readable storage medium of the present embodiment. It should be noted that, the technical solution of the storage medium and the technical solution of the three-dimensional hexahedral mesh generating method belong to the same concept, and details of the technical solution of the storage medium, which are not described in detail, can be referred to the description of the technical solution of the three-dimensional hexahedral mesh generating method.
An embodiment of the present application also provides a chip storing a computer program which, when executed by the chip, implements the steps of the method for generating a three-shaped hexahedral mesh.
The foregoing describes certain embodiments of the present application. Other embodiments are within the scope of the following claims. In some cases, the actions or steps recited in the claims can be performed in a different order than in the embodiments and still achieve desirable results. In addition, the processes depicted in the accompanying figures do not necessarily require the particular order shown, or sequential order, to achieve desirable results. In some embodiments, multitasking and parallel processing are also possible or may be advantageous.
The computer instructions include computer program code that may be in source code form, object code form, executable file or some intermediate form, etc. The computer readable medium may include: any entity or device capable of carrying the computer program code, a recording medium, a U disk, a removable hard disk, a magnetic disk, an optical disk, a computer Memory, a Read-Only Memory (ROM), a random access Memory (RAM, random Access Memory), an electrical carrier signal, a telecommunications signal, a software distribution medium, and so forth. It should be noted that the computer readable medium contains content that can be appropriately scaled according to the requirements of jurisdictions in which such content is subject to legislation and patent practice, such as in certain jurisdictions in which such content is subject to legislation and patent practice, the computer readable medium does not include electrical carrier signals and telecommunication signals.
It should be noted that, for the sake of simplicity of description, the foregoing method embodiments are all expressed as a series of combinations of actions, but it should be understood by those skilled in the art that the present application is not limited by the order of actions described, as some steps may be performed in other order or simultaneously in accordance with the present application. Further, those skilled in the art will appreciate that the embodiments described in the specification are all preferred embodiments, and that the acts and modules referred to are not necessarily all required for the present application.
In the foregoing embodiments, the descriptions of the embodiments are emphasized, and for parts of one embodiment that are not described in detail, reference may be made to the related descriptions of other embodiments.
The preferred embodiments of the application disclosed above are intended only to assist in the explanation of the application. Alternative embodiments are not intended to be exhaustive or to limit the application to the precise form disclosed. Obviously, many modifications and variations are possible in light of the above teaching. The embodiments were chosen and described in order to best explain the principles of the application and the practical application, to thereby enable others skilled in the art to best understand and utilize the application. The application is limited only by the claims and the full scope and equivalents thereof.
Claims (4)
1. A method of generating a three-dimensional hexahedral mesh, comprising:
creating a three-flow tetrahedral grid of the acquired object model;
determining points contained within the tri-shaped tetrahedral mesh And determining boundary points of the three-flow tetrahedral mesh；
The saidSetting the gaussian curvature of (2) to 0, and setting theIs set toObtaining three-stream tetrahedral mesh data, whereinB is the boundary point/>, of the three-flow tetrahedral meshIs the number of (3);
calculating the measurement of the data of the three-flow tetrahedral mesh through a discrete Ricci curvature flow equation, and determining the mesh point coordinates of the spherical tetrahedral mesh according to the calculation result to obtain the spherical tetrahedral mesh, wherein the three-flow tetrahedral mesh corresponds to the mesh points contained in the spherical tetrahedral mesh one by one;
Determining grid points contained in the tri-shaped tetrahedral grid ；
Sequentially inquiring the grid points in the tri-flow tetrahedron gridAdjacent tetrahedrons, calculating the grid pointsAdjacent tetrahedral volume sum；
Calculating grid points in the tri-shaped tetrahedral meshAverage volume of adjacent tetrahedraWherein m is the grid pointThe number of adjacent tetrahedrons in the three-flow tetrahedral mesh;
sequentially calculating grid points in the sphere tetrahedron grid Average volume of adjacent tetrahedra；
Determining grid points in the spheroid tetrahedral meshMaximum value in average volume of adjacent tetrahedrons；
And according to theTheAnd saidCalculating the volumetric compression ratio；
According to the volume compression ratioAnd corresponding grid points/>, in the spheroid tetrahedral meshEstablishing a grid cloud picture;
Extracting an isosurface according to the grid cloud image;
carrying out smoothing and sharpening treatment on the isosurface in the grid cloud picture through a preset image processing algorithm to obtain at least one topological area;
Determining grid points contained in the spheroid tetrahedral mesh And in the spheroid tetrahedral mesh with the mesh pointsConnected grid edges;
Calculating the average value of the lengths of the grid edges, and adjusting the edge length parameters of the grid edges according to the average value;
sequentially assembling hexahedral grid blocks in the at least one topological area according to the side length parameters of the grid sides to obtain hexahedral grids;
Querying grid points contained in the spheroid tetrahedral mesh Grid point coordinates of (a);
determining the corresponding relation of grid points between the sphere tetrahedral grid and the hexahedral grid;
And projecting the hexahedral mesh to a three-manifold based on the corresponding relation and the grid point coordinates to obtain a target three-manifold hexahedral mesh.
2. The method of claim 1, wherein the sequentially computing grid points in the spheroid tetrahedral meshAverage volume of adjacent tetrahedraComprising:
Querying the corresponding relation of grid points between the spheroid tetrahedral grids and the tri-manifold tetrahedral grids, and determining the grid points contained in the spheroid tetrahedral grids based on the query result ；
Sequentially inquiring in the tetrahedron grid of the sphere and the grid pointAdjacent tetrahedrons, the grid points/>, are calculatedAdjacent tetrahedral volume sum；
Calculating grid points in the spheroid tetrahedral meshAverage volume of adjacent tetrahedraWherein n is the grid pointThe number of adjacent tetrahedrons in the spheroid tetrahedral mesh.
3. The method of claim 1, wherein creating the three-shaped tetrahedral mesh of the acquired object model comprises:
Setting surface grid generation parameters of the target object model;
generating a surface unstructured grid according to the surface grid generation parameters and the target model object;
Setting a volume generation parameter of the surface unstructured grid, and generating the three-flow tetrahedral grid according to the volume generation parameter and the surface unstructured grid.
4. A three-shaped hexahedral mesh generating device, comprising:
A grid creation module configured to create a tri-manifold tetrahedral grid of the acquired object model;
a metric adjustment module configured to determine points contained within the tri-shaped tetrahedral mesh And determining boundary points/>, of the tri-shaped tetrahedral mesh; Will saidSetting the gaussian curvature of (2) to 0, and setting theIs set toObtaining three-stream tetrahedral mesh data, whereinB is the boundary point/>, of the three-flow tetrahedral meshIs the number of (3); calculating the measurement of the data of the three-flow tetrahedral mesh through a discrete Ricci curvature flow equation, and determining the mesh point coordinates of the spherical tetrahedral mesh according to the calculation result to obtain the spherical tetrahedral mesh, wherein the three-flow tetrahedral mesh corresponds to the mesh points contained in the spherical tetrahedral mesh one by one;
A volume calculation module configured to determine grid points contained in the tri-shaped tetrahedral mesh ; Sequentially querying in the tri-shaped tetrahedron grid, and the grid pointsAdjacent tetrahedrons, the grid points/>, are calculatedAdjacent tetrahedral volume sum; Calculating grid points/>, in the tri-shaped tetrahedral meshAverage volume of adjacent tetrahedronsWherein m is the grid pointThe number of adjacent tetrahedrons in the tri-shaped tetrahedron mesh is calculated, and the grid points/>, in the spheroid tetrahedron mesh is calculated in turnAverage volume of adjacent tetrahedra；
A region dividing module configured to determine grid points in the spheroid tetrahedral meshMaximum value in average volume of adjacent tetrahedrons; And according to theTheAnd saidCalculate the volumetric compression ratio; According to the volume compression ratioAnd corresponding grid points/>, in the spheroid tetrahedral meshEstablishing a grid cloud picture; extracting an isosurface according to the grid cloud image; carrying out smoothing and sharpening treatment on the isosurface in the grid cloud picture through a preset image processing algorithm to obtain at least one topological area;
a mesh inverse mapping module configured to determine mesh points contained in the spheroid tetrahedral mesh And in the spheroid tetrahedral mesh with the mesh pointsConnected grid edges; calculating the average value of the lengths of the grid edges, and adjusting the edge length parameters of the grid edges according to the average value; sequentially assembling hexahedral grid blocks in the at least one topological area according to the side length parameters of the grid sides to obtain hexahedral grids; querying grid points/>, contained in the spheroid tetrahedral meshGrid point coordinates of (a); determining the corresponding relation of grid points between the sphere tetrahedral grid and the hexahedral grid; and projecting the hexahedral mesh to a three-manifold based on the corresponding relation and the grid point coordinates to obtain a target three-manifold hexahedral mesh.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202410421282.6A CN118015223B (en) | 2024-04-09 | 2024-04-09 | Method and device for generating three-manifold hexahedral grid |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202410421282.6A CN118015223B (en) | 2024-04-09 | 2024-04-09 | Method and device for generating three-manifold hexahedral grid |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN118015223A CN118015223A (en) | 2024-05-10 |
| CN118015223B true CN118015223B (en) | 2024-06-18 |
Family
ID=90954306
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202410421282.6A Active CN118015223B (en) | 2024-04-09 | 2024-04-09 | Method and device for generating three-manifold hexahedral grid |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN118015223B (en) |
Family Cites Families (13)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2006201857A (en) * | 2005-01-18 | 2006-08-03 | Fujitsu Ltd | Hexahedron mesh generating method and device |
| CN103236088B (en) * | 2013-04-16 | 2015-07-15 | 北京金阳普泰石油技术股份有限公司 | Three-dimensional geological structure modeling method and system based on composite grid |
| CN104572575B (en) * | 2015-01-27 | 2017-10-13 | 南京航空航天大学 | A kind of especially big deformation dynamics mess generation method |
| CN108717493B (en) * | 2018-05-21 | 2022-03-01 | 杭州电子科技大学 | Two-dimensional area automatic decomposition method for structured quadrilateral mesh generation |
| CN109377561B (en) * | 2018-10-26 | 2024-01-19 | 北京工商大学 | Conformal geometry-based digital-analog surface grid generation method |
| CN114222659A (en) * | 2019-08-14 | 2022-03-22 | 西门子工业软件公司 | Method of generating a structural grid, method of using a structural grid, computer program and computer readable medium |
| CN112862972B (en) * | 2021-02-22 | 2023-08-18 | 北京工商大学 | Surface structure grid generation method |
| CN113987856A (en) * | 2021-09-26 | 2022-01-28 | 杭州电子科技大学 | Complex multi-constraint structure grid generation method based on frame field |
| CN116030218A (en) * | 2021-10-26 | 2023-04-28 | 中国石油化工股份有限公司 | Tetrahedral mesh dividing method, device, system and storage medium |
| CN115965764A (en) * | 2022-11-21 | 2023-04-14 | 中国地质大学（北京） | Complex geological model tetrahedral mesh division method and device for calculating surface subsidence |
| CN116071519B (en) * | 2023-03-06 | 2023-06-20 | 清华大学 | Image processing method and device for generating grid model based on harmonic mapping |
| CN117077294B (en) * | 2023-10-12 | 2024-03-12 | 中国空气动力研究与发展中心计算空气动力研究所 | Parameterization-based structural grid generation method, apparatus, device and medium |
| CN117610354A (en) * | 2023-11-23 | 2024-02-27 | 中国核动力研究设计院 | Method and device for mapping parallelepiped grid |
-
2024
- 2024-04-09 CN CN202410421282.6A patent/CN118015223B/en active Active
Non-Patent Citations (2)
| Title |
|---|
| 基于有限元弹性变形运算的全六面体网格生成方法研究;邹静;纪洪广;;计算力学学报;20110415(第02期);全文 * |
| 网格之星：国家数值风洞的通用型结构网格生成软件;庞宇飞;《空气动力学学报》;20200815;第第38卷卷(第第4期677期);677-686 * |
Also Published As
| Publication number | Publication date |
|---|---|
| CN118015223A (en) | 2024-05-10 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN107392984B (en) | Method for generating animation based on face image and computing equipment | |
| CN111768477B (en) | Three-dimensional facial expression base establishment method and device, storage medium and electronic equipment | |
| Montenegro et al. | An automatic strategy for adaptive tetrahedral mesh generation | |
| CN111581776B (en) | Iso-geometric analysis method based on geometric reconstruction model | |
| CN110298922B (en) | Three-dimensional model simplification method, device and equipment | |
| CN114756944A (en) | Light-weight system and method for BIM (building information modeling), computer equipment and storage medium | |
| CN104156546B (en) | The shape face redesign method of the car panel die based on T battens | |
| CN112560125B (en) | Generation method, generation system and preprocessing system of lattice structure model | |
| CN112598773A (en) | Method and device for realizing skeleton skin animation | |
| CN116385672A (en) | Construction method of three-dimensional terrain scene model data product | |
| CN117974817B (en) | Efficient compression method and system for texture data of three-dimensional model based on image coding | |
| JP2023076820A (en) | Image processing method, device, electronic device, and storage medium | |
| CA2396419C (en) | System and method for multi-resolution fairing of non-manifold models | |
| CN116071529A (en) | Three-dimensional model processing method and device | |
| CN118313177A (en) | Cloth simulation method and device, electronic equipment, medium and product | |
| CN118015223B (en) | Method and device for generating three-manifold hexahedral grid | |
| CN113191016B (en) | Body expression model-based multi-material product modeling and analyzing integrated method | |
| CN107330209B (en) | Modeling wall intelligent template implementation method based on parametric design | |
| CN115841063B (en) | Sliding dynamic grid generation method and device for dynamic derivative numerical simulation | |
| CN112414396A (en) | Method and device for measuring position of object model in real scene, storage medium and equipment | |
| CN115972202B (en) | Method, robot, device, medium and product for controlling operation of mechanical arm | |
| Pujol et al. | Adaptive approximation of signed distance fields through piecewise continuous interpolation | |
| CN114140508A (en) | Method, system and equipment for generating three-dimensional reconstruction model and readable storage medium | |
| CN110689616B (en) | Water delivery channel parametric modeling method based on three-dimensional digital earth | |
| CN112819961B (en) | Simplified grid deformation method and device based on micro-computing |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |