CN112199783A - Finite element simulation method, device and equipment for vehicle frame and storage medium - Google Patents
Finite element simulation method, device and equipment for vehicle frame and storage medium Download PDFInfo
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Abstract
The invention belongs to the technical field of vehicle design and discloses a finite element simulation method, a finite element simulation device, finite element simulation equipment and a storage medium for a vehicle frame. The method comprises the following steps: acquiring a three-dimensional model of a frame to be simulated; converting the three-dimensional model into a two-dimensional shell unit structure model; carrying out gridding treatment on the two-dimensional shell unit structure model to obtain a gridded two-dimensional model; performing rivet connection optimization processing on the gridding two-dimensional model to obtain a target two-dimensional model; carrying out welding connection simplification processing on the target two-dimensional model to obtain a finite element simulation model of the frame to be simulated; and (5) carrying out frame stress verification according to the finite element simulation model. Through the mode, the three-dimensional model is converted into the two-dimensional model, the two-dimensional model is simpler in grid division compared with the three-dimensional model, the number of grids is less, the scale of the finite element model of the frame is effectively reduced, the rivet connection is optimized, the welding connection is simplified, and the efficiency of finite element analysis is improved.
Description
Technical Field
The invention relates to the technical field of automobile design, in particular to a finite element simulation method, a finite element simulation device, finite element simulation equipment and a storage medium for a frame.
Background
With the rapid development of the automobile industry along with the progress of science and technology, automobiles occupy more and more important positions in the life of people. As part of the vehicle assembly, the frame is subjected to loads from the road and complex loads. The frame is provided with relevant parts such as an engine, a transmission system, a suspension, a cargo box and the like, bears various forces and moments transmitted to the frame, and has a complex working state. Therefore, the frame has enough rigidity and strength, reliability and service life. The method for optimally designing the vehicle frame is very important, the design period of the vehicle can be shortened, and the reliability of the safety performance of the vehicle can be improved.
The most used in the current frame design is tests: a large amount of simplified calculation is carried out on the frame according to the classical mechanics theory, the frame is designed according to the experience of a designer, a sample vehicle is trial-manufactured after the scheme is completed, and the sample vehicle is tested to judge whether the design is reasonable or not. The method has certain reliability, but makes the design blind and the development cycle of the automobile longer. The application of the finite element method is not common, the grid quality is poor when the finite element model of the frame is made in the prior art, the workload is increased, the scale of the finite element model is increased, and the stress concentration around the rivet influences the judgment of the overall strength of the frame.
The above is only for the purpose of assisting understanding of the technical aspects of the present invention, and does not represent an admission that the above is prior art.
Disclosure of Invention
The invention mainly aims to provide a finite element simulation method, a finite element simulation device, a finite element simulation equipment and a storage medium for a frame, and aims to solve the technical problems of reducing the scale of a finite element model of the frame and improving the efficiency of finite element analysis.
In order to achieve the aim, the invention provides a finite element simulation method of a frame, which comprises the following steps:
acquiring a three-dimensional model of a frame to be simulated;
converting the three-dimensional model into a two-dimensional shell unit structure model;
carrying out gridding treatment on the two-dimensional shell unit structure model to obtain a gridded two-dimensional model;
performing rivet connection optimization processing on the gridding two-dimensional model to obtain a target two-dimensional model;
carrying out welding connection simplification processing on the target two-dimensional model to obtain a finite element simulation model of the frame to be simulated;
and carrying out frame stress verification according to the finite element simulation model.
Optionally, the gridding the two-dimensional shell unit structure model to obtain a gridded two-dimensional model includes:
carrying out independent gridding processing on the target hole corresponding to the two-dimensional shell unit structure model to obtain a hole part gridding model;
carrying out gridding division processing on the models except the target hole in the two-dimensional shell unit structure model to obtain a partial gridding model;
and obtaining a gridding two-dimensional model according to the hole part gridding model and the partial gridding model.
Optionally, the performing, by a single mesh division process, a target hole corresponding to the two-dimensional shell unit structure model includes:
adding a marking surface on the periphery of the target hole according to the pressing surface of the rivet to obtain the target hole with the marking surface;
and carrying out independent mesh division processing on the target hole with the imprinting surface.
Optionally, the performing rivet connection optimization processing on the gridding two-dimensional model to obtain a target two-dimensional model includes:
and converting the rivet connecting units in the gridding two-dimensional model into beam structure units with the same cross sections as the rivets to obtain a target two-dimensional model.
Optionally, the converting the rivet connection unit in the gridding two-dimensional model into a beam structure unit with the same cross section as that of the rivet to obtain a target two-dimensional model includes:
acquiring rivet connection unit information in the gridding two-dimensional model;
determining rivet section information and a rivet-connected shell unit according to the rivet connection unit information;
determining a remote point of action from the rivet-connected shell element;
selecting a beam unit structure, wherein the section information corresponding to the beam unit structure is the same as the section information of the rivet;
and connecting the remote action points through the beam unit structure to obtain a target two-dimensional model.
Optionally, the determining a remote point of action from the rivet-connected shell element comprises:
determining a marking surface corresponding to the rivet connecting hole according to the shell unit connected by the rivet;
and simulating the associated remote action point according to the imprinting surface.
Optionally, the performing weld connection simplification processing on the target two-dimensional model to obtain a finite element simulation model of the frame to be simulated includes:
determining the position of a welding seam in the target two-dimensional model and parts to be welded;
and connecting the parts to be welded at the welding seam position in a binding contact mode to obtain a finite element simulation model of the frame to be simulated.
In addition, in order to achieve the above object, the present invention further provides a finite element simulation apparatus for a vehicle frame, including:
the acquisition module is used for acquiring a three-dimensional model of the frame to be simulated;
the conversion module is used for converting the three-dimensional model into a two-dimensional shell unit structure model;
the gridding module is used for carrying out gridding processing on the two-dimensional shell unit structure model to obtain a gridding two-dimensional model;
an optimization module used for carrying out rivet connection optimization processing on the gridding two-dimensional model to obtain a target two-dimensional model
The simplification module is used for carrying out welding connection simplification processing on the target two-dimensional model to obtain a finite element simulation model of the frame to be simulated;
and the verification module is used for verifying the stress of the frame according to the finite element simulation model.
In addition, in order to achieve the above object, the present invention further provides a finite element simulation device for a vehicle frame, including: a memory, a processor and a frame finite element simulation program stored on said memory and executable on said processor, said frame finite element simulation program being configured to implement the steps of the frame finite element simulation method as described above.
In addition, to achieve the above object, the present invention further provides a storage medium, on which a finite element frame simulation program is stored, and the finite element frame simulation program implements the steps of the finite element frame simulation method as described above when executed by a processor.
The method comprises the steps of obtaining a three-dimensional model of a frame to be simulated; converting the three-dimensional model into a two-dimensional shell unit structure model; carrying out gridding treatment on the two-dimensional shell unit structure model to obtain a gridded two-dimensional model; performing rivet connection optimization processing on the gridding two-dimensional model to obtain a target two-dimensional model; carrying out welding connection simplification processing on the target two-dimensional model to obtain a finite element simulation model of the frame to be simulated; and (5) carrying out frame stress verification according to the finite element simulation model. Through the mode, the three-dimensional model is converted into the two-dimensional model, the two-dimensional model is simpler in grid division compared with the three-dimensional model, the number of grids is less, the scale of the finite element model of the frame is effectively reduced, the rivet connection is optimized, the welding connection is simplified, and the efficiency of finite element analysis is improved.
Drawings
FIG. 1 is a schematic structural diagram of a finite element simulation device of a frame in a hardware operating environment according to an embodiment of the present invention;
FIG. 2 is a schematic flow chart of a finite element simulation method of a vehicle frame according to a first embodiment of the present invention;
FIG. 3 is a schematic view of a three-dimensional model of a vehicle frame according to an embodiment of the finite element simulation method of a vehicle frame of the present invention;
FIG. 4 is a schematic diagram showing a comparison between a three-dimensional model of a vehicle frame and a two-dimensional shell unit structure model according to an embodiment of the finite element simulation method of the vehicle frame of the present invention;
FIG. 5 is a schematic flow chart of a finite element simulation method for a vehicle frame according to a second embodiment of the present invention;
FIG. 6 is a schematic diagram showing a grid comparison of an embodiment of a finite element simulation method of a vehicle frame according to the present invention;
FIG. 7 is a schematic flow chart diagram of a finite element simulation method for a vehicle frame according to a third embodiment of the present invention;
FIG. 8 is a schematic diagram comparing a rivet connection unit and a beam structure unit according to an embodiment of the finite element simulation method of a vehicle frame of the present invention;
FIG. 9 is a schematic flow chart diagram of a finite element simulation method for a vehicle frame according to a fourth embodiment of the present invention;
FIG. 10 is a block diagram of a finite element simulation apparatus for a vehicle frame according to a first embodiment of the present invention.
The implementation, functional features and advantages of the objects of the present invention will be further explained with reference to the accompanying drawings.
Detailed Description
It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.
Referring to fig. 1, fig. 1 is a schematic structural diagram of a finite element simulation device of a vehicle frame in a hardware operating environment according to an embodiment of the present invention.
As shown in fig. 1, the finite element simulation apparatus of a vehicle frame may include: a processor 1001, such as a Central Processing Unit (CPU), a communication bus 1002, a user interface 1003, a network interface 1004, and a memory 1005. Wherein a communication bus 1002 is used to enable connective communication between these components. The user interface 1003 may include a Display screen (Display), an input unit such as a Keyboard (Keyboard), and the optional user interface 1003 may also include a standard wired interface, a wireless interface. The network interface 1004 may optionally include a standard wired interface, a WIreless interface (e.g., a WIreless-FIdelity (WI-FI) interface). The Memory 1005 may be a Random Access Memory (RAM) Memory, or may be a Non-Volatile Memory (NVM), such as a disk Memory. The memory 1005 may alternatively be a storage device separate from the processor 1001.
Those skilled in the art will appreciate that the configuration shown in FIG. 1 does not constitute a limitation of the finite element simulation device for a vehicle frame, and may include more or fewer components than shown, or some components in combination, or a different arrangement of components.
As shown in fig. 1, a memory 1005 as a storage medium may include an operating system, a network communication module, a user interface module, and a frame finite element simulation program.
In the finite element simulation device of the vehicle frame shown in fig. 1, the network interface 1004 is mainly used for data communication with a network server; the user interface 1003 is mainly used for data interaction with a user; the processor 1001 and the memory 1005 of the finite element simulation device of the frame of the invention can be arranged in the finite element simulation device of the frame, the finite element simulation device of the frame calls a finite element simulation program stored in the memory 1005 through the processor 1001, and executes the finite element simulation method of the frame provided by the embodiment of the invention.
The embodiment of the invention provides a finite element simulation method for a vehicle frame, and referring to fig. 2, fig. 2 is a schematic flow chart of a first embodiment of the finite element simulation method for the vehicle frame.
In this embodiment, the finite element simulation method for the vehicle frame includes the following steps:
step S10: and acquiring a three-dimensional model of the frame to be simulated.
It can be understood that the executing main body of this embodiment is a finite element simulation device of the vehicle frame, and the finite element simulation device of the vehicle frame may be a computer or a server installed with a finite element simulation program of the vehicle frame, or may be other devices that can achieve the same function, which is not limited in this embodiment.
Referring to fig. 3, fig. 3 is a schematic diagram of a three-dimensional model of a vehicle frame according to an embodiment of the finite element simulation method of the vehicle frame, the vehicle frame assembly is bilaterally symmetrical, and main parts comprise a longitudinal beam 1, a cross beam 2, a cross beam connecting plate 3 and a vehicle body connecting plate 4; the parts are riveted and welded. The frame assembly is modeled by UG (Unigraphics), SolidWorks, CATIA, Pro/E and other software to obtain the geometric model shown in FIG. 3.
It should be noted that, the process of obtaining the three-dimensional model of the frame to be simulated may be to previously model the frame assembly through modeling software, output a file in a general format, and send it to the finite element simulation device of the frame, and the finite element simulation device of the frame reads the file in the general format to obtain the three-dimensional model of the frame to be simulated.
Step S20: and converting the three-dimensional model into a two-dimensional shell unit structure model.
It can be understood that the three-dimensional model is imported into finite element analysis software, the three-dimensional model is converted into a two-dimensional shell element structure model, the shell elements are given according to the actual thickness, the finite element analysis software can be ANSA Workbench or HyperMeSh software, and a user can display the three-dimensional structure by displaying the thickness on the two-dimensional shell element structure model.
Referring to fig. 4, fig. 4 is a schematic diagram illustrating a comparison between a three-dimensional model of a vehicle frame and a two-dimensional shell unit structure model according to an embodiment of the finite element simulation method of the vehicle frame of the present invention.
Step S30: and carrying out gridding treatment on the two-dimensional shell unit structure model to obtain a gridded two-dimensional model.
It should be noted that, in this embodiment, the gridding process may be implemented by processing manners such as free grid division, mapping grid division, and hybrid grid division, or the holes connected by the rivets and other important holes may be divided separately, and then the rest of the holes may be subjected to grid division, so that the gridding process is performed on the two-dimensional shell unit structure model, and the gridded two-dimensional model is obtained.
It is to be understood that the step of implementing the gridding process by free grid division may include: the size and density distribution of the grid are automatically controlled by using an intelligent size control technology of ANSYS finite element analysis software, and preset parameters can be input to realize the control of the size of the grid, the density distribution, the selection of a sub-grid algorithm and the like. The step of implementing the gridding process by mapping the grid division may include: and cutting the blocks into a series of hexahedrons by using an ANSYS Boolean operation function, and then carrying out mapping grid division on the cut blocks. The step of implementing the gridding process by hybrid grid-division may include: according to the characteristics of the longitudinal beam, the transverse beam connecting plate and the vehicle body connecting plate, various grid division modes such as free mode, mapping mode, sweeping mode and the like are adopted respectively to form a finite element model with the best comprehensive effect. In order to improve the calculation precision and reduce the calculation time, firstly, hexahedron meshes are divided into areas suitable for scanning and mapping mesh division, and then areas which cannot be divided and must be divided by tetrahedron free meshes are freely divided into the areas by adopting hexahedron units with middle nodes.
Step S40: and performing rivet connection optimization processing on the gridding two-dimensional model to obtain a target two-dimensional model.
The rivet connection optimization process may include optimizing rivet connection by simulating connection modes such as bolts and spot welding, or may include obtaining a target two-dimensional model by using beam elements instead of rivet connection.
Step S50: and carrying out welding connection simplification processing on the target two-dimensional model to obtain a finite element simulation model of the frame to be simulated.
It will be appreciated that the components are joined by binding contact at the location of the weld of the two components, thereby achieving a simplified handling of the weld joint.
Step S60: and carrying out frame stress verification according to the finite element simulation model.
It should be noted that the stress condition of the frame can be verified by inputting stress condition parameters to the finite element simulation model according to actual conditions, and powerful verification means is provided for vehicle development.
In the embodiment, a three-dimensional model of the frame to be simulated is obtained; converting the three-dimensional model into a two-dimensional shell unit structure model; carrying out gridding treatment on the two-dimensional shell unit structure model to obtain a gridded two-dimensional model; performing rivet connection optimization processing on the gridding two-dimensional model to obtain a target two-dimensional model; carrying out welding connection simplification processing on the target two-dimensional model to obtain a finite element simulation model of the frame to be simulated; and (5) carrying out frame stress verification according to the finite element simulation model. Through the mode, the three-dimensional model is converted into the two-dimensional model, the two-dimensional model is simpler in grid division compared with the three-dimensional model, the number of grids is less, the scale of the finite element model of the frame is effectively reduced, the rivet connection is optimized, the welding connection is simplified, and the efficiency of finite element analysis is improved.
Referring to FIG. 5, FIG. 5 is a schematic flow chart of a finite element simulation method of a vehicle frame according to a second embodiment of the present invention.
Based on the first embodiment, in the step S30, the finite element simulation method for a vehicle frame in this embodiment includes:
step S301: and carrying out independent grid division processing on the target holes corresponding to the two-dimensional shell unit structure model to obtain a hole part gridding model.
It can be understood that the separate mesh division processing may be a series of trilateral, quadrilateral or hexagon dividing the periphery of the target hole, or may be performed by adding an imprinting surface to the target hole according to the rivet pressing surface and then performing the separate mesh division processing on the imprinting surface.
Further, in order to separately partition the target holes and make the simulated stress result around the rivet hole more accurate, the separately meshing the target holes corresponding to the two-dimensional shell unit structure model includes: adding a marking surface on the periphery of the target hole according to the pressing surface of the rivet to obtain the target hole with the marking surface; and carrying out independent mesh division processing on the target hole with the imprinting surface.
It is understood that the stamping surface refers to an area divided from a large plane, and in this embodiment, the stamping surface has the same shape and size as the pressing surface of the rivet.
Step S302: and carrying out meshing processing on the models except the target hole in the two-dimensional shell unit structure model to obtain a partial meshing model.
It can be understood that the intelligent size control technology of ANSYS finite element analysis software is utilized to automatically control the size and density distribution of the grids, so as to complete the operation of carrying out the grid division processing on the models except the target holes.
Step S303: and obtaining a gridding two-dimensional model according to the hole part gridding model and the partial gridding model.
Referring to fig. 6, fig. 6 is a schematic diagram of grid comparison of an embodiment of a finite element simulation method of a vehicle frame of the present invention, which is a diagram of grid comparison of an angle of a first cross beam of the vehicle frame, where a geometric model 1 is a geometric model corresponding to a current finite element analysis model without an imprint surface added thereto, the finite element model 1 is a schematic diagram of a current finite element analysis model grid, a geometric model 2 is a geometric model obtained by adding an imprint surface to the periphery of a target hole according to a compression surface of a rivet, and a finite element model 2 is a finite element model obtained by performing gridding processing in the present embodiment, and it can be seen from the diagram that a gridding two-dimensional model obtained by performing gridding processing in the present embodiment is more explanatory for the finite element model 1 in comparison of simulation of the periphery of the rivet, and a more accurate.
According to the embodiment, the marking surface is added on the periphery of the rivet-connected hole and other important holes according to the compression surface of the rivet, and meshing is carried out on other parts after the marking surface is singly meshed, so that the quality of meshes around the rivet is improved, a more explanatory model is provided for stress analysis around the rivet, and the efficiency of finite element analysis is improved.
Referring to FIG. 7, FIG. 7 is a schematic flow chart of a finite element simulation method of a vehicle frame according to a third embodiment of the present invention.
Based on the first embodiment, in the step S40, the finite element simulation method for a vehicle frame in this embodiment includes:
step S401: and converting the rivet connecting units in the gridding two-dimensional model into beam structure units with the same cross sections as the rivets to obtain a target two-dimensional model.
Referring to fig. 8, fig. 8 is a schematic diagram showing a comparison between a rivet connection unit and a beam structure unit according to an embodiment of the finite element simulation method for a vehicle frame of the present invention, wherein the rivet is used for connecting an upper layer unit and a lower layer unit, the beam structure unit is used for connecting the upper layer unit and the lower layer unit, and the cross sections of the beam structure unit and the rivet connection unit are the same, so as to realize the optimized rivet connection.
Further, in order to convert the rivet connection unit into a beam structure unit having the same section as that of the rivet, and obtain an optimized target two-dimensional model, the step S401 includes: acquiring rivet connection unit information in the gridding two-dimensional model; determining rivet section information and a rivet-connected shell unit according to the rivet connection unit information; determining a remote point of action from the rivet-connected shell element; selecting a beam unit structure, wherein the section information corresponding to the beam unit structure is the same as the section information of the rivet; and connecting the remote action points through the beam unit structure to obtain a target two-dimensional model.
It can be understood that the rivet section information is obtained through parameter information corresponding to the three-dimensional model. In finite element analysis, when concentrated loads such as point loads are applied to the structure, stress concentration is easily caused at a stress point, so that a simulation result is inaccurate, and a remote action point has the function of transmitting the concentrated loads to elements such as lines, surfaces and the like in the result, so that the stress concentration is reduced, and the simulation precision is improved. The location of the remote point of action may be determined from the rivet, or from the beam element structure.
Further, in order to improve simulation accuracy, determining a remote action point and a transmission surface and enable a stress verification result to be more accurate, the determining the remote action point according to the shell unit connected by the rivet includes: determining a marking surface corresponding to the rivet connecting hole according to the shell unit connected by the rivet; and simulating the associated remote action point according to the imprinting surface.
It will be appreciated that prior to determining the corresponding footprint of the rivet attachment hole from the rivet attached shell element, the method further comprises: and adding an imprinting surface on the periphery of the rivet hole on the shell unit connected with the rivet according to the compression surface of the rivet, and determining a remote action point according to the imprinting surface, so that the concentrated stress is transmitted to the imprinting surface in the subsequent stress verification process, and the optimization simulation of the rivet is realized.
The model that rivet connection has been replaced through roof beam unit structure combination seal mark face and remote action point to this embodiment, has reduced the scale of frame finite element model effectively, has promoted finite element analysis's efficiency.
Referring to FIG. 9, FIG. 9 is a schematic flow chart of a finite element simulation method of a vehicle frame according to a fourth embodiment of the present invention.
Based on the first embodiment, in the step S50, the finite element simulation method for a vehicle frame in this embodiment includes:
step S501: and determining the position of the welding seam in the target two-dimensional model and the parts to be welded.
It can be understood that the positions of the welding seams and the parts to be welded are determined according to the corresponding parameters of the three-dimensional model of the vehicle frame.
Step S502: and connecting the parts to be welded at the welding seam position in a binding contact mode to obtain a finite element simulation model of the frame to be simulated.
It will be appreciated that reasonable tolerances can be set when it is desired to establish a weld so that a binding contact is automatically established between the two components, thereby reducing the amount of work.
In the embodiment, the welding connection of the parts is simplified into the connection of the parts at the position of the welding line of the two parts in a binding contact mode, so that the scale of the finite element model of the frame is effectively reduced, and the efficiency of finite element analysis is improved.
In addition, an embodiment of the present invention further provides a storage medium, where a finite element frame simulation program is stored on the storage medium, and when executed by a processor, the finite element frame simulation program implements the steps of the finite element frame simulation method described above.
Referring to fig. 10, fig. 10 is a structural block diagram of a finite element simulation device of a vehicle frame according to a first embodiment of the invention.
As shown in fig. 10, a finite element simulation apparatus for a vehicle frame according to an embodiment of the present invention includes: .
The obtaining module 10 is used for obtaining a three-dimensional model of the frame to be simulated.
Referring to fig. 3, fig. 3 is a schematic diagram of a three-dimensional model of a vehicle frame according to an embodiment of the finite element simulation method of the vehicle frame, the vehicle frame assembly is bilaterally symmetrical, and main parts comprise a longitudinal beam 1, a cross beam 2, a cross beam connecting plate 3 and a vehicle body connecting plate 4; the parts are riveted and welded. The frame assembly is modeled by UG (Unigraphics), SolidWorks, CATIA, Pro/E and other software to obtain the geometric model shown in FIG. 3.
It should be noted that, in the process of acquiring the three-dimensional model of the frame to be simulated, the frame assembly may be modeled in advance through modeling software, a file in a general format is output and sent to the acquisition module 10, and the acquisition module 10 reads the file in the general format to acquire the three-dimensional model of the frame to be simulated.
A conversion module 20 for converting the three-dimensional model into a two-dimensional shell unit structure model.
It can be understood that the three-dimensional model is imported into finite element analysis software, the three-dimensional model is converted into a two-dimensional shell element structure model, the shell elements are given according to the actual thickness, the finite element analysis software can be ANSA Workbench or HyperMeSh software, and a user can display the three-dimensional structure by displaying the thickness on the two-dimensional shell element structure model.
Referring to fig. 4, fig. 4 is a schematic diagram illustrating a comparison between a three-dimensional model of a vehicle frame and a two-dimensional shell unit structure model according to an embodiment of the finite element simulation method of the vehicle frame of the present invention.
And the gridding module 30 is used for gridding the two-dimensional shell unit structure model to obtain a gridded two-dimensional model.
It should be noted that, in this embodiment, the gridding process may be implemented by processing manners such as free grid division, mapping grid division, and hybrid grid division, or the holes connected by the rivets and other important holes may be divided separately, and then the rest of the holes may be subjected to grid division, so that the gridding process is performed on the two-dimensional shell unit structure model, and the gridded two-dimensional model is obtained.
It is to be understood that the step of implementing the gridding process by free grid division may include: the size and density distribution of the grid are automatically controlled by using an intelligent size control technology of ANSYS finite element analysis software, and preset parameters can be input to realize the control of the size of the grid, the density distribution, the selection of a sub-grid algorithm and the like. The step of implementing the gridding process by mapping the grid division may include: and cutting the blocks into a series of hexahedrons by using an ANSYS Boolean operation function, and then carrying out mapping grid division on the cut blocks. The step of implementing the gridding process by hybrid grid-division may include: according to the characteristics of the longitudinal beam, the transverse beam connecting plate and the vehicle body connecting plate, various grid division modes such as free mode, mapping mode, sweeping mode and the like are adopted respectively to form a finite element model with the best comprehensive effect. In order to improve the calculation precision and reduce the calculation time, firstly, hexahedron meshes are divided into areas suitable for scanning and mapping mesh division, and then areas which cannot be divided and must be divided by tetrahedron free meshes are freely divided into the areas by adopting hexahedron units with middle nodes.
And the optimization module 40 is used for performing rivet connection optimization processing on the gridding two-dimensional model to obtain a target two-dimensional model.
The rivet connection optimization process may include optimizing rivet connection by simulating connection modes such as bolts and spot welding, or may include obtaining a target two-dimensional model by using beam elements instead of rivet connection.
And the simplifying module 50 is used for carrying out welding connection simplifying processing on the target two-dimensional model to obtain a finite element simulation model of the frame to be simulated.
It will be appreciated that the components are joined by binding contact at the location of the weld of the two components, thereby achieving a simplified handling of the weld joint.
And the verification module 60 is used for verifying the stress of the frame according to the finite element simulation model.
It should be noted that the stress condition of the frame can be verified by inputting stress condition parameters to the finite element simulation model according to actual conditions, and powerful verification means is provided for vehicle development.
It should be understood that the above is only an example, and the technical solution of the present invention is not limited in any way, and in a specific application, a person skilled in the art may set the technical solution as needed, and the present invention is not limited thereto.
In the embodiment, a three-dimensional model of a frame to be simulated is obtained; converting the three-dimensional model into a two-dimensional shell unit structure model; carrying out gridding treatment on the two-dimensional shell unit structure model to obtain a gridded two-dimensional model; performing rivet connection optimization processing on the gridding two-dimensional model to obtain a target two-dimensional model; carrying out welding connection simplification processing on the target two-dimensional model to obtain a finite element simulation model of the frame to be simulated; and (5) carrying out frame stress verification according to the finite element simulation model. Through the mode, the three-dimensional model is converted into the two-dimensional model, the two-dimensional model is simpler in grid division compared with the three-dimensional model, the number of grids is less, the scale of the finite element model of the frame is effectively reduced, the rivet connection is optimized, the welding connection is simplified, and the efficiency of finite element analysis is improved.
It should be noted that the above-described work flows are only exemplary, and do not limit the scope of the present invention, and in practical applications, a person skilled in the art may select some or all of them to achieve the purpose of the solution of the embodiment according to actual needs, and the present invention is not limited herein.
In addition, the technical details that are not described in detail in this embodiment can be referred to the finite element simulation method of the vehicle frame provided by any embodiment of the present invention, and are not described herein again.
In an embodiment, the gridding module 30 is further configured to perform separate grid division processing on the target holes corresponding to the two-dimensional shell unit structure model to obtain a hole part gridding model;
carrying out gridding division processing on the models except the target hole in the two-dimensional shell unit structure model to obtain a partial gridding model;
and obtaining a gridding two-dimensional model according to the hole part gridding model and the partial gridding model.
In an embodiment, the gridding module 30 is further configured to add a mark surface to the periphery of the target hole according to the pressing surface of the rivet, so as to obtain the target hole with the mark surface;
and carrying out independent mesh division processing on the target hole with the imprinting surface.
In an embodiment, the optimizing module 40 is further configured to convert the rivet connection units in the gridding two-dimensional model into beam structure units having the same cross section as that of the rivets, so as to obtain a target two-dimensional model.
In an embodiment, the optimization module 40 is further configured to obtain rivet connection unit information in the gridding two-dimensional model;
determining rivet section information and a rivet-connected shell unit according to the rivet connection unit information;
determining a remote point of action from the rivet-connected shell element;
selecting a beam unit structure, wherein the section information corresponding to the beam unit structure is the same as the section information of the rivet;
and connecting the remote action points through the beam unit structure to obtain a target two-dimensional model.
In an embodiment, the optimizing module 40 is further configured to determine, according to the rivet-connected shell unit, a stamp face corresponding to the rivet-connecting hole;
and simulating the associated remote action point according to the imprinting surface.
In an embodiment, the simplified module 50 is further configured to determine the positions of the weld joints in the target two-dimensional model and the parts to be welded;
and connecting the parts to be welded at the welding seam position in a binding contact mode to obtain a finite element simulation model of the frame to be simulated.
Further, it is to be noted that, in this document, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or system that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or system. Without further limitation, an element defined by the phrase "comprising an … …" does not exclude the presence of other like elements in a process, method, article, or system that comprises the element.
The above-mentioned serial numbers of the embodiments of the present invention are merely for description and do not represent the merits of the embodiments.
Through the above description of the embodiments, those skilled in the art will clearly understand that the method of the above embodiments can be implemented by software plus a necessary general hardware platform, and certainly can also be implemented by hardware, but in many cases, the former is a better implementation manner. Based on such understanding, the technical solution of the present invention or portions thereof that contribute to the prior art may be embodied in the form of a software product, where the computer software product is stored in a storage medium (e.g. Read Only Memory (ROM)/RAM, magnetic disk, optical disk), and includes several instructions for enabling a terminal device (e.g. a mobile phone, a computer, a server, or a network device) to execute the method according to the embodiments of the present invention.
The above description is only a preferred embodiment of the present invention, and not intended to limit the scope of the present invention, and all modifications of equivalent structures and equivalent processes, which are made by using the contents of the present specification and the accompanying drawings, or directly or indirectly applied to other related technical fields, are included in the scope of the present invention.
Claims (10)
1. A finite element simulation method of a frame is characterized by comprising the following steps:
acquiring a three-dimensional model of a frame to be simulated;
converting the three-dimensional model into a two-dimensional shell unit structure model;
carrying out gridding treatment on the two-dimensional shell unit structure model to obtain a gridded two-dimensional model;
performing rivet connection optimization processing on the gridding two-dimensional model to obtain a target two-dimensional model;
carrying out welding connection simplification processing on the target two-dimensional model to obtain a finite element simulation model of the frame to be simulated;
and carrying out frame stress verification according to the finite element simulation model.
2. The finite element simulation method of a vehicle frame according to claim 1, wherein the gridding the two-dimensional shell element structure model to obtain a gridded two-dimensional model comprises:
carrying out independent gridding processing on the target hole corresponding to the two-dimensional shell unit structure model to obtain a hole part gridding model;
carrying out gridding division processing on the models except the target hole in the two-dimensional shell unit structure model to obtain a partial gridding model;
and obtaining a gridding two-dimensional model according to the hole part gridding model and the partial gridding model.
3. The finite element simulation method of a vehicle frame according to claim 2, wherein the individual meshing processing of the target holes corresponding to the two-dimensional shell element structure model comprises:
adding a marking surface on the periphery of the target hole according to the pressing surface of the rivet to obtain the target hole with the marking surface;
and carrying out independent mesh division processing on the target hole with the imprinting surface.
4. The finite element simulation method of a vehicle frame according to claim 1, wherein the performing rivet connection optimization processing on the gridded two-dimensional model to obtain a target two-dimensional model comprises:
and converting the rivet connecting units in the gridding two-dimensional model into beam structure units with the same cross sections as the rivets to obtain a target two-dimensional model.
5. The finite element simulation method of a frame according to claim 4, wherein the step of converting the rivet connecting unit in the gridding two-dimensional model into a beam structure unit with the same section as that of the rivet to obtain a target two-dimensional model comprises the following steps:
acquiring rivet connection unit information in the gridding two-dimensional model;
determining rivet section information and a rivet-connected shell unit according to the rivet connection unit information;
determining a remote point of action from the rivet-connected shell element;
selecting a beam unit structure, wherein the section information corresponding to the beam unit structure is the same as the section information of the rivet;
and connecting the remote action points through the beam unit structure to obtain a target two-dimensional model.
6. The finite element simulation method of a vehicle frame of claim 5, wherein said determining a remote point of action from said rivet connected shell element comprises:
determining a marking surface corresponding to the rivet connecting hole according to the shell unit connected by the rivet;
and simulating the associated remote action point according to the imprinting surface.
7. The finite element simulation method of a frame according to claim 1, wherein the step of simplifying the welding connection of the target two-dimensional model to obtain the finite element simulation model of the frame to be simulated comprises the following steps:
determining the position of a welding seam in the target two-dimensional model and parts to be welded;
and connecting the parts to be welded at the welding seam position in a binding contact mode to obtain a finite element simulation model of the frame to be simulated.
8. A finite element simulation device for a vehicle frame, the finite element simulation device comprising:
the acquisition module is used for acquiring a three-dimensional model of the frame to be simulated;
the conversion module is used for converting the three-dimensional model into a two-dimensional shell unit structure model;
the gridding module is used for carrying out gridding processing on the two-dimensional shell unit structure model to obtain a gridding two-dimensional model;
the optimization module is used for performing rivet connection optimization processing on the gridding two-dimensional model to obtain a target two-dimensional model;
the simplification module is used for carrying out welding connection simplification processing on the target two-dimensional model to obtain a finite element simulation model of the frame to be simulated;
and the verification module is used for verifying the stress of the frame according to the finite element simulation model.
9. A finite element simulation apparatus for a vehicle frame, the apparatus comprising: memory, a processor and a frame finite element simulation program stored on the memory and executable on the processor, the frame finite element simulation program being configured to implement the steps of the frame finite element simulation method of any of claims 1 to 7.
10. A storage medium having stored thereon a finite element frame simulation program which when executed by a processor implements the steps of the finite element frame simulation method of any of claims 1 to 7.
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