A method for simulating material damage of headlight lampshades using efgm in car crashes

Abstract

The invention discloses a method for simulating breakage of a lampshade material of a car headlamp by adopting an EFGM (Element Free Galerkin Method) in car collision. The method comprises the steps of performing discrete element processing on a lampshade by adopting a tetrahedron unit, and presetting a background mesh; endowing the lampshade with a plastic damage constitutive material, wherein separation occurs when bearing force between discrete points is judged by adopting a cohesion element fracture method, namely, a fracture effect is expressed; and calibrating constitutive parameters of the lampshade of a corresponding car model and parameters of an EFGM algorithm through a test method: assembling the lampshade into the complete car model, and performing simulative analysis on complete car collision: if a simulation process and a simulation result of the complete car collision meet expected true conditions, giving out part damage assessment; and if the simulation process and the simulation result of the complete car collision do not meet the expected true conditions, adjusting the model. The EFGM introducing the cohesion element fracture method avoids the mesh-dependence defect of a conventional FEM (Finite Element Method), so that random characteristics of a crack path can be ensured, the material performance can be expressed more truly, and a collision event can be recovered more truly.

Description

technical field [0001] The invention belongs to the field of automobile collision modeling, in particular to a method for simulating the damage of headlight lampshade materials by using EFGM in automobile collision. Background technique [0002] The application of CAE technology in the automotive industry has been gradually improved. From the design of auto parts to the performance analysis of the whole vehicle; from the rigidity of the car structure to the analysis of the internal and external flow field; a great guiding role. Especially in the field of automobile collision, CAE analysis has formed a series of mature NCAP and other specifications, which provide detailed analysis guidance in vehicle collision events. However, at the present stage, in the CAE simulation of vehicle collision events, FEM is the main method. Although FEM has the advantages of high efficiency, stability and high accuracy, it also has some unavoidable defects. In the simulation evaluation of br...

AI Technical Summary

Problems solved by technology

Among these relatively mature and highly commercialized meshless technologies, SPH is more suitable for describing the flow behavior of materials with strong fluidity and materials, while DEM has the problem of insufficient accuracy in evaluating the strength of materials.

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