Vibration Transfer Path Analysis Of A Coach Body Based On Rigid-Flexible Coupling Model

With the reliability of CAE on going improving, the technology has been a coordinative method with the structure mechanics and the experiment in the field of vehicle design and development. And for CAE method, rigid-flexible coupling modeling and TPA are two popular techniques in settling down vehicle vibration&noise problems.The beginning was given to the research by reading related papers to make profiles of two areas clear, which were multi-body dynamics and TPA. Then, the FE model of a coach and its modal calculation were completed with HyperMesh based on existing CAD model. For the next step, a multi-body dynamic model and a TPA model were built with the output file produced by the modal calculation. ADAMS/Car and Virtual. Lab were softwares used during these procedures. In the following step, according to different velocities of the coach, a series of simulations were performed with the multi-body dynamic model. And the acceleration of driver seat point in three directions, X Y Z, was obtained, as well as the load given by suspension to the coach body. With the data gained in the dynamics simulations, TPA calculations were also finished. Via outcome analyzing, the vibration transfer situations for every path under different working conditions (60km/h,80km/h,100km/h) were acquired. After TPA, ADAMS/Insight was used to optimize bushings which were related to transfer paths that have large amount of contributions.After these simulations, it is clear that path transfer situations do not stay unchanged under different working conditions because of variation of the load frequency spectrum. Macroscopic impact to driver seat point vibration of every path was gained by computing average value of frequency spectrum peak, instead of a single peak analysis. Of course, these calculations were conducted under every working condition. After the optimization in ADAMS/Insight, the multi-body dynamic model was modified according to optimization results. And, the simulation based on it indicated that vibration condition of the coach was improved. After the whole research in the paper described above, the optimization of the coach on vibration&noise problems would be much easy.