CN-122021131-A - Honeycomb sandwich plate finite element fine modeling method and system for strength check

CN122021131ACN 122021131 ACN122021131 ACN 122021131ACN-122021131-A

Abstract

The invention provides a honeycomb sandwich plate finite element fine modeling method and system for strength check, which comprise the steps of building a honeycomb sandwich plate fine finite element model, wherein building the honeycomb sandwich plate fine finite element model comprises the steps of analyzing the composition and the stress characteristics of a honeycomb sandwich plate, formulating a failure mode and a modeling criterion, simplifying and cleaning a three-dimensional geometric model, simulating and meshing the simplified three-dimensional geometric model, simulating the gluing assembly relation of each element of the honeycomb sandwich plate, acquiring material parameters, creating physical properties and simulating boundary conditions, solving and calculating the honeycomb sandwich plate fine finite element model, and performing strength check prediction according to the strength criterion. Based on the product composition and stress characteristics, the invention establishes the fine finite element model of the honeycomb sandwich plate, realizes the technical state of highly reducing the actual product, accurately predicts and evaluates the strength characteristics and failure modes of the honeycomb sandwich plate, and guides the technical effects of structural design and weight reduction work of the spacecraft.

Inventors

MA CHAO
CHEN YE
Xiao Yakai
CHEN JING
FENG SHULIN
CHEN QIANG

Assignees

上海卫星工程研究所

Dates

Publication Date: 20260512
Application Date: 20260104

Claims (10)

1. The finite element fine modeling method for the honeycomb sandwich plate for strength check is characterized by comprising the following steps of: step S1, establishing a fine finite element model of the honeycomb sandwich plate according to the composition and the stress characteristics of the honeycomb sandwich plate; S2, solving and calculating the fine finite element model of the honeycomb sandwich plate; And step S3, performing strength check prediction according to the strength criterion.
2. The method for fine modeling of a honeycomb sandwich panel for strength check according to claim 1, wherein the building of the fine finite element model of the honeycomb sandwich panel according to the composition and the stress characteristics of the honeycomb sandwich panel comprises the following steps: s11, analyzing the composition and the stress characteristics of the honeycomb sandwich plate; step S12, according to the stress characteristics of the honeycomb sandwich plate, setting a failure mode and a modeling criterion; Step S13, simplifying and cleaning the three-dimensional geometric model of the honeycomb sandwich plate; step S14, simulating and meshing the simplified three-dimensional geometric model; step S15, simulating the gluing and assembling relationship of each element of the honeycomb sandwich plate; S16, material parameters of all elements are actually measured by using a furnace-following test piece, material modulus and strength data are obtained, then all the elements are endowed, and physical properties are created; And S17, substituting the fine finite element model of the honeycomb sandwich plate into a finite element model of a spacecraft, connecting with structural members of adjacent honeycomb sandwich plates, accurately simulating boundary conditions of the fine finite element model of the honeycomb sandwich plate, and applying displacement constraint and load under the finite element model of the spacecraft to calculate.
3. The method for fine modeling of a honeycomb sandwich panel for strength check according to claim 1, wherein the solving and calculating of the fine finite element model of the honeycomb sandwich panel comprise: And carrying out buckling analysis on the fine finite element model of the honeycomb sandwich plate to obtain a critical load coefficient, carrying out static analysis to obtain a use static stress, carrying out frequency response analysis to obtain a use dynamic stress, and calculating a safety margin according to the use dynamic stress.
4. The method for fine modeling of a honeycomb sandwich panel for strength check according to claim 1, wherein the strength check prediction according to the strength criterion comprises: the strength criteria include a critical load factor criterion, an allowable stress criterion and a safety margin criterion; the critical load coefficient criterion is that the critical load coefficient is larger than 2; The allowable stress criterion comprises that the using stress of an aluminum alloy material is smaller than 255MPa, the using stress of a magnesium alloy material is smaller than 120MPa, the using shear stress of a foaming adhesive is smaller than 3.5MPa, and the using stress of a quasi-isotropic carbon fiber material is smaller than 450MPa; The safety margin criterion comprises that the safety margin of the carbon fiber composite material is larger than 0.25, and the safety margin of the metal material is larger than 0.
5. The method for finite element fine modeling of a honeycomb sandwich panel for strength check according to claim 2, wherein the analyzing the composition and stress characteristics of the honeycomb sandwich panel comprises: the honeycomb sandwich plate consists of an upper panel, a lower panel, a honeycomb core, an embedded part, a buried frame, a reinforcing sheet and a scraping sheet, and is a composite material structure product formed by bonding with an adhesive; the honeycomb sandwich plate is characterized in that the upper panel, the lower panel, the embedded frame, the reinforcing sheet and the scraping sheet bear in-plane tension, compression and bending moment, and the honeycomb core and the embedded part bear transverse shearing force.
6. The method for finite element fine modeling of a honeycomb sandwich panel for strength check according to claim 2, wherein the step of formulating a failure mode and modeling criteria according to the stress characteristics of the honeycomb sandwich panel comprises the steps of: The failure modes of the honeycomb sandwich plate comprise integral instability, local instability of a panel, local instability of a honeycomb core, shearing of the honeycomb core, crushing and damage of the honeycomb core, plastic deformation of the panel and cracking of foaming glue; The modeling criterion comprises the steps of accurately simulating the bearing elements and the cementing assembly relation, reflecting the force transmission characteristics of the product and comprehensively predicting the failure mode of the honeycomb sandwich panel.
7. The method for finite element fine modeling of a honeycomb sandwich panel for strength check according to claim 2, wherein the simplifying and cleaning of the three-dimensional geometric model of the honeycomb sandwich panel comprises: Reasonably simplifying and cleaning a three-dimensional geometric model of the honeycomb sandwich plate by adopting three-dimensional design software, wherein the method comprises the steps of deleting secondary geometric features of all bearing elements and reserving main geometric features of all bearing elements, wherein the secondary geometric features comprise tiny holes and round corners on all bearing elements; cutting the panel and the honeycomb core according to the geometric property and the material property of the three-dimensional model, and supplementing and establishing the embedded part and the foaming glue around the embedded frame.
8. The method for finite element fine modeling of a honeycomb sandwich panel for strength check according to claim 2, wherein the simulating and meshing of the simplified three-dimensional geometric model comprises: And (3) importing the simplified and cleaned three-dimensional geometric model into finite element simulation analysis software, selecting proper units for simulation according to the geometric characteristics and stress characteristics of each element, and independently carrying out grid division, wherein the upper and lower panels, the reinforcing sheets and the embedded frames are of typical thin-wall structures, adopting triangle and quadrilateral shell unit simulation, and adopting pentahedron and hexahedral solid unit simulation for a honeycomb core, an embedded part, foaming glue and a scraping sheet.
9. The method for finite element fine modeling of a honeycomb sandwich panel for strength check according to claim 2, wherein the simulation of the glue joint assembly relationship of each element of the honeycomb sandwich panel comprises: And simulating the gluing assembly relation of each element of the honeycomb sandwich plate by adopting a gluing contact method, creating an interface unit on the contact boundary of each component, calculating a contact stiffness matrix based on a punishment factor, and then giving the interface unit to glue each component.
10. A honeycomb sandwich panel finite element fine modeling system for strength verification, comprising: The fine modeling module is used for establishing a fine finite element model of the honeycomb sandwich plate according to the composition and the stress characteristics of the honeycomb sandwich plate; the solving and calculating module is used for solving and calculating the fine finite element model of the honeycomb sandwich plate; and the checking prediction module performs strength checking prediction according to the strength criterion.

Description

Honeycomb sandwich plate finite element fine modeling method and system for strength check Technical Field The invention relates to the technical field of spacecraft structures, in particular to a method and a system for finite element fine modeling of a honeycomb sandwich plate for strength check. Background In the structural design of a spacecraft, a honeycomb sandwich plate is widely applied to various space structures due to the light weight and high strength performance of the honeycomb sandwich plate. In order to ensure that the honeycomb sandwich panel meets the strength requirements in the actual working environment, an accurate strength check must be performed. The finite element analysis method plays an important role in the strength analysis and prediction of the honeycomb sandwich panel as an important means of modern computational mechanics. In the prior art, patent document CN202011262400.1 discloses a finite element modeling method of a honeycomb sandwich plate, wherein a honeycomb core is equivalent to an orthotropic homogeneous plate, and a skin is equivalent to an isotropic plate. The method is suitable for researching the raw material grade of the honeycomb sandwich plate, but the model ignores components such as a buried frame, foam adhesive, a scraping blade and the like and connection relation, and has a larger gap with a spacecraft honeycomb sandwich plate structure product which is practically applied in aerospace engineering. Patent document CN202210048940.2 provides a method and a system for rapidly extracting a shell simulation model based on a satellite cabin plate structure, but the method focuses on improving modeling efficiency by using a digitizing means, and does not improve model and calculation accuracy. Patent document CN202210650144.6 proposes a system-level method for designing a honeycomb sandwich panel, which automatically creates high-quality grid cells, but the method focuses on rapidly generating a honeycomb core finite element grid, and does not solve the problem of connection assembly between the honeycomb core and other elements. Patent document cn202410265159.X proposes a method for calculating the vibration response of a honeycomb sandwich panel, determining a free vibration equation from strain energy and kinetic energy of upper and lower fiber layers and a honeycomb layer, and calculating the vibration response. However, the method focuses on mathematical modeling and equation deduction of the vibration problem of the honeycomb sandwich plate, and belongs to basic theoretical research. Patent document CN201210035017.1 proposes a method for measuring and calculating the natural frequency of a honeycomb sandwich structure, which is to measure the bending rigidity of the honeycomb sandwich plate and the shear modulus of the core layer, and substitute the formula to calculate the natural frequency of the honeycomb sandwich plate. The method is not suitable for checking the strength of the honeycomb sandwich plate. In summary, in view of the above-mentioned problems in the prior art, research on a method and a system for finite element fine modeling of a honeycomb sandwich panel facing strength check is a critical task to be solved in the present day. Disclosure of Invention Aiming at the defects in the prior art, the invention aims to provide a finite element fine modeling method and a finite element fine modeling system for a honeycomb sandwich plate for strength check. The honeycomb sandwich plate finite element fine modeling method for strength check comprises the following steps of S1, establishing a honeycomb sandwich plate fine finite element model according to the composition and stress characteristics of the honeycomb sandwich plate, S2, solving and calculating the honeycomb sandwich plate fine finite element model, and S3, performing strength check prediction according to strength criteria. The method comprises the steps of S11, analyzing the composition and the stress characteristics of a honeycomb sandwich plate, S12, establishing failure modes and modeling criteria according to the stress characteristics of the honeycomb sandwich plate, S13, simplifying and cleaning a three-dimensional geometric model of the honeycomb sandwich plate, S14, simulating and meshing the simplified three-dimensional geometric model, S15, simulating the gluing assembly relation of each element of the honeycomb sandwich plate, S16, obtaining material modulus and strength data by using material parameters of each element measured along with a furnace test piece, giving each element, creating physical properties, S17, substituting the fine finite element model of the honeycomb sandwich plate into a spacecraft finite element model, connecting the fine finite element model of the honeycomb sandwich plate with structural members of an adjacent honeycomb sandwich plate, accurately simulating the boundary conditions of the fine finite element model of the honeycomb sandwich plate,