Finite element analysis of nonlinear stiffness characteristics of air spring

Nonlinear stiffness characteristics of an air spring were analyzed (FEA) by a nonlinear finite element analysis package. The hyperelastic material model, Mooney-Rivlin, was applied to simulate the rubber material and the rebar material was adopted to build the cord fabric layers. The air in the cavity of air spring was represented by the hydrostatic fluid elements of ABAQUS and 3D shell elements were used to build the rigid model. The contacts between deformable body and contacted bodies were also analyzed. The spring characteristic of the air spring was calculated under certain constraints and loads by the FEA model. The results both from the simulation and the tests are compared and an excellent agreement is achieved, which indicates that the present method is sufficiently reliable for predicting the nonlinear stiffness characteristics of an air spring.