【摘要】 以有限元模态分析和试验模态分析的相关理论为基础,对某轿车白车身的模态进行了研究。首先,在HyperMesh建立了白车身有限元模型,并用梁单元模拟焊点。在Nastran软件中用Lanczos方法对白车身进行了模态分析,得到白车身的固有频率及各阶振型。其次,采用随机信号对白车身进行两点激励,用多点拾振方法采集响应信号,将信号处理后,得到白车身的固有频率及对应的振型。通过对比有限元模态分析结果和试验结果,验证了所建有限元模型的有效性。更多还原

【Abstract】 Based on the finite element modal analysis and testing modal analysis theory,the modal of a car body in white studied. First of all,the finite element model of the car body in white was built in the software of HyperMesh,and the welding-spot was simulated with beam element. A modal analysis was done to the car body in white by the software of Nastran using the Lanczos method,and get the results of the natural frequency and vibration modes. Secondly,using the random signal with two points to stimulate the car body,and using multi-point method of pick-up response signal,the signal was processed to obtain the natural frequency and vibration modes of the car body in white. Comparing the results of the simulation with that of test,The effectiveness of the finite element model is verified.更多还原