关键词: 商用车；白车身；HyperMesh；模态研究；有限元分析

Abstract: In this paper, HyperMesh software is used to establish a simulation model for the body in white of a commercial vehicle, study its natural frequency and vibration mode under free state, and carry out the modal test verification of the body in white. The test data are compared with the simulation analysis results. The frequency error of the finite element analysis and the frequency of the test results is within 5% except for the first order, which indicates that the finite element model is relatively accurate and the calculation results are reliable, The simulation results can well reflect the vibration characteristics of the actual structure. The overall modal frequency of the body in white is far from the second order unbalanced excitation frequency, which is less likely to cause vehicle resonance. The estimated vehicle comfort and vehicle fatigue life meet the requirements. The evaluation of structural characteristics by means of simulation can save the cost of development and test, shorten the development cycle and provide a theoretical basis for design.

Key words: Commercial vehicle; Body in white; HyperMesh; Modality study; Finite element analysis