Impact Simulation And Optimal Design Of The Front Longeron

This article uses the finite element software such as HyperMesh, LS-DYNA etc, to simulate and analysis the automotive front longeron collision. And take the four components of the thin-walled straight beam to make quasi-static crushing experiments, using the test data to verify the accuracy of the simulation data. In this paper, a model of front longeron as the research object, a numerical simulation of the simulation model is set up and make improvement on the front longeron structure, induced by adding groove and the internal reinforced plate to improve the energy absorption characteristics of front longeron. In this paper the main research work done is as follows:(1) Access to a large number of the automobile front longeron thin-walled structure crashworthiness research literature, understand the domestic and foreign research status about the subject, the research methods of crashworthiness for front longeron include experimental method and finite element simulation method. Evaluation index of front longeron properties, mainly include the total energy absorption, Specific Energy Absorption, peak of pounding force and mean load.(2) Using HyperMesh, LS-DYNA etc, based on the HyperMesh, research problems such as mesh modeling process of front longeron structure, high quality of the grid division, definition ofconnecting unit, building material model and so on. Analysis several key factors affecting the collision finite element simulation, such as cell size, material properties, friction and so on, providing the reference to set parameter when establish the finite element model.(3) Summing up the optimization methods that promote the energy absorption properties of the front longeron, and validating these methods. Analysising the fold wavelength of longitudinal beam in the process of collapse deformation, Studying solder joint arrangement, single cell/multi-cell, cross-sectional shape, wall thickness, etc which influence deformation mode and energy absorption performance of the front longeron, providing a reference for the front longeron structure optimization.(4) Building four groups of thin-walled straight beam artifacts, comparing the energy absorption characteristics of members through the simulation analysis, we can find one of the best components, then make quasi-static crushing experiments to verify the simulation results. Comparing the simulation results with experimental results, we can see when the components’ deformational patterns are similar, data such as the collision force and energy absorption are also similar.(5) Simulation analysis was made on the existing front longeron, by adding derivational groove and the internal reinforced plate to optimizate the structure of front longeron. Comparing the initial structure and optimizated structure, the optimized front longeron endergonic characteristic has been greatly improved.