| Leaf spring is a very important component of an automobile. Whether its design success or not is a key factor that decides the design level of the whole vehicle. It not only takes the function of transferring the forces, but influences the ride comfort and safety also. On account of its geometry nonlinear, contact nonlinear etc., the precise design of leaf spring becomes difficult. The development of advanced contact dynamics and CAE technology makes it possible to solve this problem.In this dissertation, the author studies the conventional design methods of leaf spring and various calculation models, introduces the basic assumptions and calculation formulae of point pressure method, common curvature method, combination method and finite element method. In addition, the dissertation discusses modern design method—CAE technology and introduces its meanings and applications.The optimal mathematical models for multi-leaf spring, taper-leaf spring, variable rate leaf spring and two-stage compound leaf spring are established. Using optimum design method, these springs are optimized and some engineering examples are given. The results show that the spring has the minimum weight with required strength and stiffness. The optimization method improves design efficiency of leaf spring greatly.The basic analysis methods of advanced contact dynamics theory are summarized. Considering large deformation, interleaf friction and contact simultaneously, the FEA model of one front leaf spring is built using ANSYS based on nonlinear finite element for continua and structures. Stress distribution and stiffness are obtained. The precision of spring's calculation model is improved. At the same time, a precise design method for leaf spring using APDL is proposed. The parameterized model of single taper-leaf spring and its optimum design are introduced. The results reflect the feasibility of this method.According to advanced contact dynamics theory, a new method to analyze...
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