Research On Finite Element Modeling And Lightweight For Coach-Body Frame

CAE technology is widely applied in mechanical industry along with the development of computer technology. For coach-body frame is main bearing part of whole car structure, car-body CAE method, which is based on the finite element method, catches people's attention more, and there have been great achievements in the domain domestically and oversea. Based on the investigation of the related domestic and overseas research in the domain, the finite element model of coach-body frame is established, and static analysis is carried on. Results comparison between test and analysis verifies that the finite model is correct and believable. Modal analysis point out the merits and demerits of dynamic performance, which provide consult for optimization design. In order to test the coach-body frame stiffness, dynamic stiffness test is carried on in the proving ground, and test results indicate that the coach-body fame stiffness has some space to optimize, which provides evidence and consult for lightweight.Lightweight design is another aspect of this paper. Car-body frame lightweight is propitious to reduce whole vehicle weight. Reduction of body weight can not only save materials, but also improve acceleration performance and fuel economy of the vehicle and reduce engine emission. The lightweight scheme, discussed in this paper, is based upon the results of CAE analysis and static and dynamic test, and also based upon experience of related research and engineer practice, according to which, 174.7 Kg of the coach-body frame weight is reduced, which comes up to the goal of 5% weight to decrease, but stress distributing change little and the coach-body frame stiffness performance meets requirements.Taper section and custom section beams are widely adopted in the process of model set-up, which is a feature of this paper. Modeling of welding points and suspension improves analysis precision in a way. Especially the welding points disposal, which is widely applied in saloon car, is a good attempt in this paper. On the side, shell-beam model solves the problem of modeling time and analysis precision, and gives prominence to emphases, and the model is more practical.