CN118194664A - Automatic finite element grid quality inspection method and system - Google Patents

Abstract

The invention discloses a finite element grid quality automatic checking method and system, which belong to the technical field of CAE performance simulation, and firstly, the type of a finite element grid to be checked is judged; the finite element grid type comprises triangular grid cells and quadrilateral grid cells; if the finite element mesh type is a triangular mesh unit, respectively checking the quality of the finite element mesh according to the sequence of a twisting Angle Skewness, a minimum height MIN HEIGHT, a minimum Angle min Angle and a maximum Angle max Angle; if the finite element grid type is a quadrilateral grid unit, performing quadrilateral grid quality inspection according to the sequence of the Warping Angle warp, the Warping Angle Skewness, the minimum height MIN HEIGHT, the minimum Angle min Angle and the maximum Angle max Angle. The method can reduce investment of enterprises in grid division, improve research and development efficiency and reduce labor intensity of engineers.

Description

Automatic finite element grid quality inspection method and system

Technical Field

The invention belongs to the technical field of CAE performance simulation, and particularly relates to a finite element grid quality automatic inspection method and system.

Background

In the development process of the automobile body structure performance, CAE performance simulation is an indispensable link, and 60% -80% of time is occupied by the finite element grid division of the automobile structure in the whole CAE simulation process. In general, in development of vehicle model products, the same part can be repeatedly subjected to geometric structure modification and adjustment, during which finite element mesh quality is required to be checked manually, and then mesh quality adjustment is performed, and if automatic mesh quality check and adjustment are realized, the key for realizing automatic finite element mesh division is realized.

Disclosure of Invention

In order to solve the defects of the prior art, the invention aims to provide a finite element grid quality automatic checking method and a finite element grid quality automatic checking system, wherein the checking method firstly judges the type of a grid to be checked: if the cell type is triangle, respectively checking the quality of the grid according to the sequence of minimum height of the twisting angles Skewness and MIN HEIGHT, minimum Angle of min Angle and maximum Angle of max Angle; if the unit type is quadrilateral, performing quadrilateral grid quality inspection according to the sequence of the minimum height of the Warping Angle warp Angle Skewness and MIN HEIGHT, the minimum Angle of the min Angle and the maximum Angle of the max Angle; the method can reduce investment of enterprises in grid division, improve research and development efficiency and reduce labor intensity of engineers.

The invention is realized by the following technical scheme:

In a first aspect, the present invention provides a method for automatically checking the quality of a finite element grid, which specifically includes the following steps: firstly, judging the type of the finite element grid to be checked; the finite element grid type comprises triangular grid cells and quadrilateral grid cells; if the finite element mesh type is a triangular mesh unit, respectively checking the quality of the finite element mesh according to the sequence of a twisting Angle Skewness, a minimum height MIN HEIGHT, a minimum Angle min Angle and a maximum Angle max Angle; if the finite element grid type is a quadrilateral grid unit, performing quadrilateral grid quality inspection according to the sequence of the Warping Angle warp, the Warping Angle Skewness, the minimum height MIN HEIGHT, the minimum Angle min Angle and the maximum Angle max Angle.

Further, the twist angle Skewness for the triangular mesh unit is obtained by:

Let three vertices of triangle be P ₁、P₂、P₃ respectively, and calculate the twist angles Skewness of the three vertices respectively, first calculate the point P ₁ to the edge Vector V ₁, edge/>, of midpoint mid1 of (1)Mid-point to side/>Vector V ₂ at the midpoint of (a) and calculating the included angle/>The absolute value of the included angle minus 90 degrees is the grid torsion angle of the point P ₁; then, respectively calculating grid twist angles of the points P ₂、P₃ according to the method; and finally, respectively comparing the grid torsion angles of the points P ₁、P₂、P₃ with target values, and if one or more torsion angles are larger than the target torsion angle value, judging that the torsion angle value of the triangle unit does not meet the requirement.

Further, the minimum height MIN HEIGHT for a triangular mesh unit is obtained by:

and setting three vertexes of the triangle as P ₁、P₂、P₃ respectively, calculating the vertical heights of the three vertexes relative to opposite sides of the triangle respectively, and setting the vertical heights as h ₁、h₂、h₃ respectively, and if one of the height values is smaller than the target minimum height value, judging that the minimum height value of the triangle unit does not meet the requirement.

Further, the minimum angle MinAngle for a triangular mesh unit is obtained by:

three vertexes of the triangle are respectively P ₁、P₂、P₃, and three angles corresponding to the three vertexes are respectively If one of the angles is smaller than the target minimum angle value, judging that the triangle unit does not meet the requirement of the minimum angle value;

The maximum angle MaxAngle for a triangular mesh unit is obtained by:

Three vertexes of the triangle are respectively P ₁、P₂、P₃, and three angles corresponding to the three vertexes are respectively three angles If one of the angles is larger than the target minimum angle value, the triangle unit is judged to not meet the requirement of the minimum angle value.

Further, warp value warp for the quadrangular mesh unit is obtained by the following method:

by dividing the diagonal of the quadrangle, the quadrangle can be divided into two triangles, and because the quadrangle has two diagonals, the quadrangle can be divided into two groups of triangle pairs, and the angles of each group of triangle pairs are calculated respectively If the value of one angle is larger than the target warping value, judging that the quadrilateral unit is not satisfied.

Further, the warp value Skewness for the quadrangular mesh unit is obtained by the following method:

Four vertexes of the quadrangle are set as P ₁、P₂、P₃、P₄ respectively, and four sides are calculated respectively Is then/>And/>Is taken as a vector, will/>And/>Takes the midpoint connecting line of the two vectors as a vector, calculates the included angle/>Will include an angle/>Subtracting the value of 90 degrees, taking an absolute value, and if the result is larger than the target distortion value, judging that the quadrilateral unit does not meet the requirement.

Further, the minimum height MIN HEIGHT for a quadrilateral mesh unit is obtained by:

And (3) setting four vertexes of the quadrangle as P ₁、P₂、P₃、P₄ respectively, calculating the vertical heights h ₁、h₂、h₃、h₄ of the four vertexes and opposite sides respectively, and if one or more height values in the four heights are smaller than the target minimum height value, judging that the quadrangle unit does not meet the requirement.

Further, the minimum angle MinAngle for a quadrilateral mesh unit is obtained by:

four vertexes of the quadrangle are respectively P ₁、P₂、P₃、P₄, and angles at the four vertexes are respectively And calculating whether one or more angles in the four angles are smaller than a target minimum angle value, and if so, judging that the quadrilateral unit does not meet the requirement.

The maximum angle MaxAngle for a quadrilateral mesh unit is obtained by:

four vertexes of the quadrangle are respectively P ₁、P₂、P₃、P₄, and angles at the four vertexes are respectively And calculating whether one or more angles in the four angles are larger than a target minimum angle value, and if so, judging that the quadrilateral unit does not meet the requirement.

In a second aspect, the present invention also provides an automated finite element mesh quality inspection system, comprising:

the judging module is used for judging the type of the finite element grid to be checked;

a first checking module for checking the grid quality of the triangle grid unit;

and the second checking module is used for checking the grid quality of the quadrilateral grid unit.

In a third aspect, a terminal is provided, including:

one or more processors;

A memory for storing the one or more processor-executable instructions;

wherein the one or more processors are configured to:

The method according to the first aspect of the embodiment of the invention is performed.

In a fourth aspect, a non-transitory computer readable storage medium is provided, which when executed by a processor of a terminal, enables the terminal to perform the method according to the first aspect of the embodiments of the invention.

In a fifth aspect, an application product is provided, which when running at a terminal causes the terminal to perform the method according to the first aspect of the embodiments of the invention.

Compared with the prior art, the invention has the following advantages:

The method and the system for automatically checking the quality of the finite element grids are an indispensable link of the finite element grid division function of the full-automatic automobile structure, the implementation of the link can reduce the investment of enterprises in grid division, improve the research and development efficiency, reduce the labor intensity of engineers and provide a feasible technical solution for the pretreatment automation of the finite element grids of the automobile structure.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below. Like elements or portions are generally identified by like reference numerals throughout the several figures. In the drawings, elements or portions thereof are not necessarily drawn to scale.

FIG. 1 is a flow chart of an automated finite element mesh quality inspection method of the present invention;

FIG. 2 is a finite element mesh of an automotive panel shell structure;

FIG. 3 is a diagram showing triangle cell twist Skewness;

FIG. 4 is a diagram showing a minimum height MIN HEIGHT of a triangle unit;

FIG. 5 is a diagram of the triangle unit minimum/maximum angles Min angle/Max angle index;

FIG. 6 is a graph showing the warp Warping index of the quadrangular unit;

FIG. 7 is a graph showing the index of quadrilateral cell distortion Skewness;

FIG. 8 is a diagram showing the minimum height MIN HEIGHT of the quadrangular unit;

fig. 9 is a diagram of a minimum Angle Min Angle index of a quadrangular unit.

Detailed Description

For a clear and complete description of the technical scheme and the specific working process thereof, the following specific embodiments of the invention are provided with reference to the accompanying drawings in the specification:

In the present invention, unless explicitly specified and limited otherwise, the terms "mounted," "connected," "secured," and the like are to be construed broadly, and may be, for example, fixedly connected, detachably connected, or integrally formed; can be mechanically or electrically connected; either directly or indirectly, through intermediaries, or both, may be in communication with each other or in interaction with each other, unless expressly defined otherwise. The specific meaning of the above terms in the present invention can be understood by those of ordinary skill in the art according to the specific circumstances.

In the present invention, unless expressly stated or limited otherwise, a first feature "up" or "down" a second feature may be the first and second features in direct contact, or the first and second features in indirect contact via an intervening medium. Moreover, a first feature being "above," "over" and "on" a second feature may be a first feature being directly above or obliquely above the second feature, or simply indicating that the first feature is level higher than the second feature. The first feature being "under", "below" and "beneath" the second feature may be the first feature being directly under or obliquely below the second feature, or simply indicating that the first feature is less level than the second feature.

In the description of the present specification, a description referring to terms "one embodiment," "some embodiments," "examples," "specific examples," or "some examples," etc., means that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the present invention. In this specification, schematic representations of the above terms are not necessarily directed to the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples. Furthermore, the different embodiments or examples described in this specification and the features of the different embodiments or examples may be combined and combined by those skilled in the art without contradiction.

Example 1

The automobile structure finite element mesh division is mainly based on commercial finite element mesh preprocessing tools, and is commonly used as hypermesh of Altair company and ANSA of Greek BETA company in the United states. In the embodiment, a method for checking the quality of the grid, which is automated on the basis of grid generation in the grid of the plate shell, is mainly described, and the specific technical scheme is as follows:

step one: taking the plate and shell part A as an example, the part grid structure A _mesh is shown in FIG. 2. The plate shell finite element grid is generally formed by mixing a quadrangle and a triangle grid, so that the triangle grid and the quadrangle grid need to be respectively subjected to quality inspection in the whole method, wherein:

(1) Triangle mesh quality includes a distortion value Skewness, a minimum height MIN HEIGHT, a minimum angle MinAngle, a maximum angle MaxAngle;

(2) The grid quality of the quadrangle includes warp value warp, warp value Skewness, jacob, minimum height MIN HEIGHT, minimum angle MinAngle, maximum angle MaxAngle;

Specifically, in the actual grid division process of the plate-shell structure, indexes of finite element grid quality are different according to different field attributes, such as the fields of structural collision, NVH, structural durability and the like. Describing a method for automatically checking the quality of the triangular meshes by using the mesh quality index in the structural durability field, wherein the mesh quality index of the structural durability is shown in table 1;

Table 1 shows a structural durable grid quality index table

Step two: the inspection of the quality index of each grid of the triangle grid is specifically as follows:

(1) Distortion value Skewness: for the distortion value of the triangle unit, three vertices P ₁、P₂、P₃ are calculated three times, for example, vertex P ₁, and point P ₁ is calculated to the edge Vector V ₁, edge/>, of midpoint mid1 of (1)Mid-point to side/>Vector V ₂ at the midpoint of (a) and calculating the included angle/>The absolute value of the included angle minus 90 degrees is the current grid torsion angle, the torsion angles calculated by the three vertexes P ₁、P₂、P₃ are respectively compared with the target values, and if one or more torsion angles are larger than the target torsion angle value, the torsion angle value of the triangle unit is judged to not meet the requirement, as shown in figure 3;

(2) Minimum height: MIN HEIGHT: the triangle unit has three heights passing through three vertexes P ₁、P₂、P₃, h ₁、h₂、h₃ respectively, the three height values are calculated respectively, and if one of the height values is smaller than the target minimum height value, the minimum height value of the triangle unit is judged to not meet the requirement, as shown in fig. 4;

(3) Minimum angles MinAngle three vertices P ₁、P₂、P₃ of a triangle element have three angles, respectively If one of the angles is smaller than the target minimum angle value, judging that the triangle unit does not meet the requirement of the minimum angle value, as shown in fig. 5;

(4) Maximum angle MaxAngle three vertices P ₁、P₂、P₃ of the triangle unit have three angles respectively If one of the angles is larger than the target minimum angle value, judging that the triangle unit does not meet the requirement of the minimum angle value, as shown in fig. 5;

Step three: the quality index of the quadrilateral mesh is checked as follows:

(1) Warp value warp: as shown in FIG. 6, the warp value of the quadrangle is shown, the quadrangle can be divided into two triangles by dividing the diagonal of the quadrangle, and the quadrangle can be divided into two triangle pairs because the quadrangle has two diagonals, and the angles of each triangle pair can be calculated respectively If the value of one angle is larger than the target warping value, judging that the quadrilateral unit is not satisfied with the requirement;

(2) Distortion value Skewness: the distortion values of the quadrangle are calculated as shown in FIG. 7, and four sides are calculated respectively Is then/>And/>Is taken as a vector, will/>And/>Takes the midpoint connecting line of the two vectors as a vector, calculates the included angle/>Will include an angle/>Subtracting the value of 90 degrees, taking an absolute value, and if the result is larger than the target distortion value, judging that the quadrilateral unit does not meet the requirement;

(3) Minimum height MIN HEIGHT: the minimum height values of the quadrangle are calculated respectively, as shown in fig. 8, the heights h ₁、h₂、h₃、h₄ of the four vertexes P ₁、P₂、P₃、P₄ and the opposite sides are calculated respectively, and if one or more height values in the four heights are smaller than the target minimum height value, the quadrangle unit is judged to not meet the requirement;

(4) Minimum angle MinAngle: the quadrilateral unit has four vertexes P ₁、P₂、P₃、P₄, the angles of which are respectively Calculating whether one or more angles in the four angles are smaller than a target minimum angle value, and if so, judging that the quadrilateral unit does not meet the requirement;

(5) Maximum angle MaxAngle: the quadrilateral unit has four vertexes P ₁、P₂、P₃、P₄, the angles of which are respectively Calculating whether one or more angles in the four angles are larger than a target minimum angle value, and if so, judging that the quadrilateral unit does not meet the requirement;

(6) Jacob jacobian: the minimum angle and the maximum angle of the quadrangle of the jacobian main user are related, and as long as the minimum angle and the maximum angle of the quadrangle meet the target requirement in engineering application, the target value of the jacobian can meet the actual target value requirement;

In the above calculation, the angle can be calculated by two vector angles, such as vector V ₁ and vector V ₂, and the angle can be calculated by an inverse cosine function method, such as The height can be calculated by using the point multiplication of the vector and itself, and then calculating the root number of the structure, such as vector V ₁, the length of which can be expressed as/>

Example 2

The embodiment provides an automated finite element mesh quality inspection system, which comprises:

the judging module is used for judging the type of the finite element grid to be checked;

a first checking module for checking the grid quality of the triangle grid unit;

and the second checking module is used for checking the grid quality of the quadrilateral grid unit.

Example 3

A terminal may be the terminal in the above embodiment. The terminal may be a portable mobile terminal such as: smart phone, tablet computer. Terminals may also be referred to by other names, user equipment, portable terminals, etc.

Generally, the terminal includes: a processor and a memory.

The processor may include one or more processing cores, such as a 4-core processor, an 8-core processor, and the like. The processor may be implemented in at least one hardware form of DSP (DIGITAL SIGNAL Processing), FPGA (Field-Programmable gate array), PLA (Programmable Logic Array ). The processor may also include a main processor, which is a processor for processing data in an awake state, also called a CPU (Central Processing Unit ), and a coprocessor; a coprocessor is a low-power processor for processing data in a standby state. In some embodiments, the processor may incorporate a GPU (Graphics Processing Unit, image processor) for rendering and rendering of content to be displayed by the display screen. In some embodiments, the processor may also include an AI (ARTIFICIAL INTELLIGENCE ) processor for processing computing operations related to machine learning.

The memory may include one or more computer-readable storage media, which may be tangible and non-transitory. The memory may also include high-speed random access memory, as well as non-volatile memory, such as one or more magnetic disk storage devices, flash memory storage devices. In some embodiments, a non-transitory computer readable storage medium in memory is used to store at least one instruction for execution by a processor to implement a finite element mesh quality automated inspection method provided in the present application.

In some embodiments, the terminal may further optionally include: a peripheral interface and at least one peripheral. Specifically, the peripheral device includes: at least one of a radio frequency circuit, a touch display screen, a camera, an audio circuit, a positioning component and a power supply.

The peripheral interface may be used to connect at least one Input/Output (I/O) related peripheral to the processor and the memory. In some embodiments, the processor, memory, and peripheral interfaces are integrated on the same chip or circuit board; in some other embodiments, either or both of the processor, memory, and peripheral interface may be implemented on separate chips or circuit boards, which is not limiting in this embodiment.

The Radio Frequency circuit is used for receiving and transmitting RF (Radio Frequency) signals, also called electromagnetic signals. The radio frequency circuit communicates with the communication network and other communication devices via electromagnetic signals. The radio frequency circuit converts an electrical signal into an electromagnetic signal for transmission, or converts a received electromagnetic signal into an electrical signal. Optionally, the radio frequency circuit comprises: antenna systems, RF transceivers, one or more amplifiers, tuners, oscillators, digital signal processors, codec chipsets, subscriber identity module cards, and so forth. The radio frequency circuitry may communicate with other terminals via at least one wireless communication protocol. The wireless communication protocol includes, but is not limited to: the world wide web, metropolitan area networks, intranets, generation mobile communication networks (2G, 3G, 4G, and 5G), wireless local area networks, and/or WiFi (WIRELESS FIDELITY ) networks. In some embodiments, the radio frequency circuit may further include NFC (NEAR FIELD Communication) related circuits, which is not limited by the present application.

The touch display screen is used to display a UI (User Interface). The UI may include graphics, text, icons, video, and any combination thereof. Touch display screens also have the ability to collect touch signals at or above the surface of the touch display screen. The touch signal may be input to the processor for processing as a control signal. The touch display is used to provide virtual buttons and/or virtual keyboards, also known as soft buttons and/or soft keyboards. In some embodiments, the touch display screen may be one, and a front panel of the terminal is provided; in other embodiments, the touch display screen may be at least two, and is respectively disposed on different surfaces of the terminal or in a folded design; in still other embodiments, the touch display may be a flexible display disposed on a curved surface or a folded surface of the terminal. Even more, the touch display screen may be arranged in an irregular pattern other than rectangular, i.e. a shaped screen. The touch display screen may be made of materials such as an LCD (Liquid CRYSTAL DISPLAY), an OLED (Organic Light-Emitting Diode), and the like.

The camera assembly is used for acquiring images or videos. Optionally, the camera assembly 306 includes a front camera and a rear camera. In general, a front camera is used for realizing video call or self-photographing, and a rear camera is used for realizing photographing of pictures or videos. In some embodiments, the number of the rear cameras is at least two, and the rear cameras are any one of a main camera, a depth camera and a wide-angle camera, so as to realize fusion of the main camera and the depth camera to realize a background blurring function, and fusion of the main camera and the wide-angle camera to realize a panoramic shooting function and a Virtual Reality (VR) shooting function. In some embodiments, the camera assembly may further include a flash. The flash lamp can be a single-color temperature flash lamp or a double-color temperature flash lamp. The dual-color temperature flash lamp refers to a combination of a warm light flash lamp and a cold light flash lamp, and can be used for light compensation under different color temperatures.

The audio circuit is for providing an audio interface between the user and the terminal. The audio circuit may include a microphone and a speaker. The microphone is used for collecting sound waves of users and the environment, converting the sound waves into electric signals and inputting the electric signals to the processor for processing, or inputting the electric signals to the radio frequency circuit for realizing voice communication. For the purpose of stereo acquisition or noise reduction, a plurality of microphones can be respectively arranged at different parts of the terminal. The microphone may also be an array microphone or an omni-directional pickup microphone. The speaker is used to convert electrical signals from the processor or radio frequency circuitry into sound waves. The speaker may be a conventional thin film speaker or a piezoelectric ceramic speaker. When the speaker is a piezoelectric ceramic speaker, not only the electric signal can be converted into a sound wave audible to humans, but also the electric signal can be converted into a sound wave inaudible to humans for ranging and other purposes. In some embodiments, the audio circuit may also include a headphone jack.

The location component is used to locate the current geographic location of the terminal to enable navigation or LBS (Location Based Service, location-based services). The positioning component can be a positioning component based on a GPS (Global Positioning System ) of the United states and a Beidou system of China.

The power supply is used for supplying power to various components in the terminal. The power source may be alternating current, direct current, disposable or rechargeable. When the power source comprises a rechargeable battery, the rechargeable battery may be a wired rechargeable battery or a wireless rechargeable battery. The wired rechargeable battery is a battery charged through a wired line, and the wireless rechargeable battery is a battery charged through a wireless coil. The rechargeable battery may also be used to support fast charge technology.

It will be appreciated by those skilled in the art that the structure is not limiting of the terminal and may include more or less components than illustrated, or may combine certain components, or may employ a different arrangement of components.

Example 4

In an exemplary embodiment, a computer readable storage medium is also provided, on which a computer program is stored, which program, when being executed by a processor, implements a method for automated inspection of finite element mesh quality as provided by all inventive embodiments of the present application.

Any combination of one or more computer readable media may be employed. The computer readable medium may be a computer readable signal medium or a computer readable storage medium. The computer readable storage medium can be, for example, but not limited to, an electronic, magnetic, optical, electromagnetic, infrared, or semiconductor system, apparatus, or device, or a combination of any of the foregoing. More specific examples (a non-exhaustive list) of the computer-readable storage medium would include the following: an electrical connection having one or more wires, a portable computer diskette, a hard disk, a Random Access Memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or flash memory), an optical fiber, a portable compact disc read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination of the foregoing. In this document, a computer readable storage medium may be any tangible medium that can contain, or store a program for use by or in connection with an instruction execution system, apparatus, or device.

The computer readable signal medium may include a propagated data signal with computer readable program code embodied therein, either in baseband or as part of a carrier wave. Such a propagated data signal may take any of a variety of forms, including, but not limited to, electro-magnetic, optical, or any suitable combination of the foregoing. A computer readable signal medium may also be any computer readable medium that is not a computer readable storage medium and that can communicate, propagate, or transport a program for use by or in connection with an instruction execution system, apparatus, or device.

Program code embodied on a computer readable medium may be transmitted using any appropriate medium, including but not limited to wireless, wireline, optical fiber cable, RF, etc., or any suitable combination of the foregoing.

Computer program code for carrying out operations of the present invention may be written in any combination of one or more programming languages, including an object oriented programming language such as Java, smalltalk, C ++ and conventional procedural programming languages, such as the "C" programming language or similar programming languages. The program code may execute entirely on the user's computer, partly on the user's computer, as a stand-alone software package, partly on the user's computer and partly on a remote computer or entirely on the remote computer or server. In the case of a remote computer, the remote computer may be connected to the user's computer through any kind of network, including a Local Area Network (LAN) or a Wide Area Network (WAN), or may be connected to an external computer (for example, through the Internet using an Internet service provider).

Example 5

In an exemplary embodiment, an application program product is also provided, comprising one or more instructions executable by the processor 301 of the above apparatus to perform a finite element mesh quality automation inspection method as described above.

Although embodiments of the present invention have been disclosed above, they are not limited to the use listed in the description and modes of implementation. It can be applied to various fields suitable for the present invention. Additional modifications will readily occur to those skilled in the art. Therefore, the invention is not to be limited to the specific details and illustrations shown and described herein, without departing from the general concepts defined in the claims and their equivalents.

Claims (10)

1. The finite element mesh quality automatic checking method is characterized by comprising the following steps of: firstly, judging the type of the finite element grid to be checked; the finite element grid type comprises triangular grid cells and quadrilateral grid cells; if the finite element mesh type is a triangular mesh unit, respectively checking the quality of the finite element mesh according to the sequence of a twisting Angle Skewness, a minimum height MIN HEIGHT, a minimum Angle min Angle and a maximum Angle max Angle; if the finite element grid type is a quadrilateral grid unit, performing quadrilateral grid quality inspection according to the sequence of the Warping Angle warp, the Warping Angle Skewness, the minimum height MIN HEIGHT, the minimum Angle min Angle and the maximum Angle max Angle.

2. An automated finite element mesh quality inspection method according to claim 1, wherein the twist angle Skewness for the triangular mesh unit is obtained by:

Let three vertices of triangle be P ₁、P₂、P₃ respectively, and calculate the twist angles Skewness of the three vertices respectively, first calculate the point P ₁ to the edge Vector V ₁, edge/>, of midpoint mid1 of (1)Mid-point to side/>Vector V ₂ at the midpoint of (a) and calculating the included angle/>The absolute value of the included angle minus 90 degrees is the grid torsion angle of the point P ₁; then, respectively calculating grid twist angles of the points P ₂、P₃ according to the method; and finally, respectively comparing the grid torsion angles of the points P ₁、P₂、P₃ with target values, and if one or more torsion angles are larger than the target torsion angle value, judging that the torsion angle value of the triangle unit does not meet the requirement.

3. A method of automated finite element mesh quality inspection according to claim 1, wherein the minimum height MIN HEIGHT for a triangular mesh unit is obtained by:

and setting three vertexes of the triangle as P ₁、P₂、P₃ respectively, calculating the vertical heights of the three vertexes relative to opposite sides of the triangle respectively, and setting the vertical heights as h ₁、h₂、h₃ respectively, and if one of the height values is smaller than the target minimum height value, judging that the minimum height value of the triangle unit does not meet the requirement.

4. A method of automated finite element mesh quality inspection according to claim 1, wherein the minimum height MIN HEIGHT for a triangular mesh unit is obtained by:

and setting three vertexes of the triangle as P ₁、P₂、P₃ respectively, calculating the vertical heights of the three vertexes relative to opposite sides of the triangle respectively, and setting the vertical heights as h ₁、h₂、h₃ respectively, and if one of the height values is smaller than the target minimum height value, judging that the minimum height value of the triangle unit does not meet the requirement.

5. The method for automatically checking the quality of a finite element mesh according to claim 1, wherein the warp value warp for a quadrangular mesh unit is obtained by:

by dividing the diagonal of the quadrangle, the quadrangle can be divided into two triangles, and because the quadrangle has two diagonals, the quadrangle can be divided into two groups of triangle pairs, and the angles of each group of triangle pairs are calculated respectively If the value of one angle is larger than the target warping value, judging that the quadrilateral unit is not satisfied.

6. The method for automatically checking the quality of a finite element mesh according to claim 1, wherein the warp value warp for a quadrangular mesh unit is obtained by:

by dividing the diagonal of the quadrangle, the quadrangle can be divided into two triangles, and because the quadrangle has two diagonals, the quadrangle can be divided into two groups of triangle pairs, and the angles of each group of triangle pairs are calculated respectively If the value of one angle is larger than the target warping value, judging that the quadrilateral unit is not satisfied.

7.A method of automated finite element mesh quality inspection according to claim 1, wherein the minimum height MIN HEIGHT for a quadrilateral mesh unit is obtained by:

And (3) setting four vertexes of the quadrangle as P ₁、P₂、P₃、P₄ respectively, calculating the vertical heights h ₁、h₂、h₃、h₄ of the four vertexes and opposite sides respectively, and if one or more height values in the four heights are smaller than the target minimum height value, judging that the quadrangle unit does not meet the requirement.

8. A method of automated inspection of finite element mesh quality as claimed in claim 1, wherein the minimum angle MinAngle for a quadrilateral mesh unit is obtained by:

four vertexes of the quadrangle are respectively P ₁、P₂、P₃、P₄, and angles at the four vertexes are respectively And calculating whether one or more angles in the four angles are smaller than a target minimum angle value, and if so, judging that the quadrilateral unit does not meet the requirement.

The maximum angle MaxAngle for a quadrilateral mesh unit is obtained by:

four vertexes of the quadrangle are respectively P ₁、P₂、P₃、P₄, and angles at the four vertexes are respectively And calculating whether one or more angles in the four angles are larger than a target minimum angle value, and if so, judging that the quadrilateral unit does not meet the requirement.

9. An automated finite element mesh quality inspection system for implementing the method of any of claims 1-8, comprising:

the judging module is used for judging the type of the finite element grid to be checked;

a first checking module for checking the grid quality of the triangle grid unit;

and the second checking module is used for checking the grid quality of the quadrilateral grid unit.

10. A terminal, comprising:

one or more processors;

A memory for storing the one or more processor-executable instructions;

wherein the one or more processors are configured to:

Performing the method of any of claims 1-8.