Method for establishing three-dimensional rigidity model machine

Abstract

The invention belongs to the technical field of electric data processing, and particularly relates to a method for establishing a three-dimensional rigidity prototype, which comprises the following steps: S1, establishing a finite element model of a target structure, and obtaining original finite element node coordinates of the target structure; s2, rigidity simulation analysis is conducted on the target structure, and node displacement information under the specific working condition is obtained; s3, generating a deformed node coordinate according to the original finite element node coordinate and the node displacement information; s4, reconstructing the finite element model of the target structure based on the deformed node coordinates to obtain a deformed structure finite element model; and S5, generating a deformed three-dimensional structure model from the deformed structure finite element model through a grid mapping function. The three-dimensional rigidity model machine generated by the scheme can be synchronously displayed with an original structure and a peripheral structure, the deformation amount can be intuitively known, and whether a structure interference problem occurs or not is judged as a structure design constraint.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of electric data processing, and particularly relates to a method for establishing a three-dimensional stiffness prototype. BACKGROUND

[0002] The structural stiffness of an airplane is a basic structural feature affecting certain flight performances or functions, and is a key factor in airplane design, affecting structural integrity, aerodynamic performance, mechanical operation, and ensuring that each component is in accordance with vibration control and load transmission. Ignoring the stiffness problem in airplane design often leads to problems such as inconsistent force transmission routes and design intentions, difficulty in realizing mechanism functions, and even substandard performance, and thus a large cost is paid, and even airplane safety is affected. At present, in the process of airplane design, mechanism interference checking and stiffness deformation analysis are performed separately. The mechanism interference checking is mainly embodied in the form of a rigid body, and each moving part is in a theoretical form, and the checking result cannot represent the actual deformation condition of the airplane in actual work. The stiffness deformation analysis is mainly realized through simulation, and the deformation result is displayed in the form of a finite element cloud map, but in structural design, the cloud map form cannot intuitively compare the deformation amount and the interference degree of the mechanism, and thus a three-dimensional stiffness prototype is established, and the deformed structure is established as a three-dimensional model for structural design constraints and deformation interference checking. SUMMARY

[0003] To solve the above problems, the application provides a method for establishing a three-dimensional stiffness prototype, comprising the following steps:

[0004] Step S1: a finite element model of a target structure is established, and original finite element node coordinates of the target structure are obtained;

[0005] Step S2: stiffness simulation analysis is performed on the target structure, and node displacement information under a specific working condition is obtained;

[0006] Step S3: deformed node coordinates are generated according to the original finite element node coordinates and the node displacement information;

[0007] Step S4: the finite element model of the target structure is reconstructed based on the deformed node coordinates, and a deformed structure finite element model is obtained;

[0008] Step S5: the deformed structure finite element model is generated into a deformed three-dimensional structure model through a mesh mapping function.

[0009] Preferably, the Nastran software is used to perform the stiffness simulation analysis on the target structure, and finite element analysis results containing a deformation cloud map are output.

[0010] Preferably, the node displacement information is extracted from an f06 file of the finite element analysis result file.

[0011] Preferably, the calculation formula of the deformed node coordinates is:

[0012] (X i ’,Y i ’,Z i ’)=(X i0 ,Y i0 ,Z i0 )+(ΔX i ,ΔY i ,ΔZ i );

[0013] Wherein, (X i ’,Y i ’,Z i ’) represents the coordinate of the i-th node after deformation, (X i0 ,Y i0 ,Z i0 ) represents the coordinate of the i-th node before deformation, (ΔX i ,ΔY i ,ΔZ i ) represents the deformation displacement of the i-th node in three directions.

[0014] Preferably, it further comprises: step S6, exporting the deformed three-dimensional structure model into an interactive STP format file to form a three-dimensional stiffness prototype.

[0015] Preferably, in step S6, the three-dimensional stiffness prototype is used for:

[0016] Synchronous assembly with the original geometric prototype, visualizing deformation interference;

[0017] As an input condition for aerodynamic performance evaluation and system function analysis.

[0018] Preferably, in step S5, the grid mapping is realized by Hypermesh software to convert the finite element grid into a solid surface model.

[0019] The advantages of the present application include: the three-dimensional stiffness prototype generated by the present scheme can be called at any time, and is easy and simple to operate; the deformation nephogram of the previous structure cannot directly constrain the structure design, while the three-dimensional stiffness prototype generated by the present scheme can be displayed synchronously with the original structure and the surrounding structure, intuitively understanding the deformation amount, judging whether the structure interference problem occurs, and serving as a constraint for structure design. BRIEF DESCRIPTION OF DRAWINGS

[0020] Figure 1 is a method flow chart for establishing a three-dimensional stiffness prototype of a preferred embodiment of the present application. DETAILED DESCRIPTION

[0021] In order to make the technical solutions of the present application and their advantages clearer, the technical solutions of the present application will be further clearly and completely described below in conjunction with the drawings. It should be understood that the specific embodiments described herein are only some embodiments of the present application, which are used to explain the present application, but not to limit the present application. It should be noted that, for the purpose of description, only parts related to the present application are shown in the drawings, and other related parts can be referred to the general design. In the case of no conflict, the embodiments in the present application and the technical features in the embodiments can be combined to obtain new embodiments.

[0022] As shown in Figure 1 , a method for establishing a three-dimensional stiffness prototype, comprising:

[0023] Step S1: establishing a finite element model of the target structure to obtain the original finite element node coordinates of the target structure;

[0024] Step S2: performing stiffness simulation analysis on the target structure to obtain node displacement information under a specific working condition; the displacement information must be the deformation under the true scale.

[0025] Step S3: generating the deformed node coordinates according to the original finite element node coordinates and the node displacement information;

[0026] Step S4: reconstructing the finite element model of the target structure based on the deformed node coordinates to obtain the deformed structure finite element model;

[0027] Step S5: generating the deformed three-dimensional structure model through the grid mapping function of the deformed structure finite element model.

[0028] Preferably, the Nastran software is used to perform stiffness simulation analysis on the target structure, and the finite element analysis results containing the deformation cloud chart are output.

[0029] Preferably, the node displacement information is extracted from the f06 file of the finite element analysis result file.

[0030] Preferably, the calculation formula of the deformed node coordinates is:

[0031] (X i ’,Y i ’,Z i ’)=(X i0 ,Y i0 ,Z i0 )+(ΔX i ,ΔY i ,ΔZ i );

[0032] Wherein, (X i ’,Y i ’,Z i) represents the coordinate of the i th node after deformation, (X i0 , Y i0 , Z i0 ) represents the coordinate of the i th node before deformation, (ΔX i , ΔY i , ΔZ i ) represents the deformation displacement of the i th node in three directions.

[0033] Preferably, it further comprises: step S6, exporting the three-dimensional structure model after deformation into an interactive STP format file to form a three-dimensional stiffness prototype. The content of the stp file is the three-dimensional stiffness prototype, and the stiffness prototype can be used synchronously with other geometric prototypes. In the assembly of the structure, the original parts are replaced to show the state of the concerned parts after deformation for the evaluation of the aerodynamic and system.

[0034] Preferably, in step S6, the three-dimensional stiffness prototype is used for:

[0035] synchronous assembly with the original geometric prototype to visualize the deformation interference;

[0036] as an input condition for the evaluation of the aerodynamic performance and the analysis of the system function.

[0037] Preferably, in step S5, the grid mapping is realized by the Hypermesh software to convert the finite element grid into a solid surface model.

[0038] The present application establishes the three-dimensional stiffness prototype as the strength constraint condition for the design of the aircraft structure. In the past, the stiffness analysis was realized by simulation means, which could not be compared with the actual three-dimensional structure. In the present application, the creation of the structure model after deformation is realized by the means of deformation node information extraction, grid reconstruction and grid mapping to establish the three-dimensional stiffness prototype to achieve the goal of the design of the structure stiffness constraint.

[0039] The above is only a specific embodiment of the present application, but the protection scope of the present application is not limited to this. Any person skilled in the art can easily think of changes or replacements within the technical range disclosed in the present application, which should be covered in the protection scope of the present application. Therefore, the protection scope of the present application should be subject to the protection scope of the claims.

Claims

1. A method for establishing a three-dimensional stiffness prototype, characterized in that, include: Step S1: Establish the finite element model of the target structure and obtain the coordinates of the original finite element nodes of the target structure; Step S2: Perform stiffness simulation analysis on the target structure to obtain nodal displacement information under specific working conditions; Step S3: Generate the deformed node coordinates based on the original finite element node coordinates and node displacement information; Step S4: Reconstruct the finite element model of the target structure based on the deformed node coordinates to obtain the deformed structural finite element model; Step S5: Generate a deformed three-dimensional structural model from the deformed finite element model using the mesh mapping function.

2. The method for establishing a three-dimensional stiffness prototype as described in claim 1, characterized in that, The stiffness simulation analysis of the target structure was performed using Nastran software, and the finite element analysis results, including deformation contour plots, were output.

3. The method for establishing a three-dimensional stiffness prototype as described in claim 2, characterized in that, Nodal displacement information is extracted from the f06 file of the finite element analysis results file.

4. The method for establishing a three-dimensional stiffness prototype as described in claim 2, characterized in that, The formula for calculating the nodal coordinates after deformation is: (X i ’,Y i ’,Z i ’)=(X i0 ,Y i0 ,Z i0 )+(ΔX i ,ΔY i ,ΔZ i ); Among them, (X) i ', Y i ', Z i ') represents the coordinates of the i-th node after deformation, (X i0 Y i0 Z i0 () represents the coordinates of the i-th node before deformation, (ΔX) i ΔY i ΔZ i ) represents the deformation displacement of the i-th node in three directions.

5. The method for establishing a three-dimensional stiffness prototype as described in claim 2, characterized in that, It also includes step S6, which exports the deformed three-dimensional structural model as an interactive STP format file to form a three-dimensional stiffness prototype.

6. The method for establishing a three-dimensional stiffness prototype as described in claim 5, characterized in that, In step S6, the three-dimensional stiffness prototype is used for: Simultaneous assembly with the original geometric prototype, visualization of deformation interference; As input conditions for aerodynamic performance evaluation and system function analysis.

7. The method for establishing a three-dimensional stiffness prototype as described in claim 5, characterized in that, In step S5, mesh mapping is achieved using Hypermesh software, which converts the finite element mesh into a solid surface model.

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