Research On Static And Dynamic Characteristics Analysis And Lightweight For Coach-Body Frame

The methods of automobile design can be divided into the traditional design method and modern CAE technology. With the development of computer technology, CAE has become the essential analysis and optimization technology for automotive development. Finite element method, in which the continuous elastomers are divided into nodes that connect each other with finite number and size,is the core of CAE technology. In process of analysis and optimization for automotive parts and products, Finite element method can overcome the drawbacks of traditional design method and ensure product development reliable and efficient, while it avoids a large number of tests and verification process, reduces design costs,improves design efficiency and speeds up the development cycle.In the thesis, the author takes a domestic bus as an example, on the basis of UG three-dimensional model and domestic and foreign correlation research, carries on the precise modeling to some entire-bearing coach body frame utilizing ANSYS software. Considering four typical operation situation, such as the bus running with the uniform velocity; one of the wheels hanging in the air when the bus running on an uneven road; the bus braking suddenly and the bus steering quickly. The calculation of strength and stiffness of bus body's structure is expatiated. Then the modal analysis of the bus skeleton was made and natural frequency and corresponding vibration modes was gotten.Lightweight design is another aspect of this paper. The Lightweight analysis scheme, discussed in this paper, is based upon the results of CAE static and dynamic analysis, and also based upon experience of related research and engineer practice, according to which, 86 Kg of the coach-body frame weight is reduced, but stress distributing change little and the coach-body frame strength performance meets requirements.