Simulation and experimental investigation of mechanical property of air spring for vehicles

Owing to the fact that there were geometric nonlinearities, physical nonlinearities and contact nonlinearities during the working of vehicle air spring, it is difficult to estimate its mechanical property accurately using empirical formula. In recent years, with the development of nonlinear finite element theory and computer techniques, it is possible to estimate the mechanical property of air spring using nonlinear finite element method. Based on the study of an air spring used on a certain kind of vehicle suspension system, its three-dimensional finite element model was developed. In the model, the cord reinforced rubber bellow was simulated by both Mooney-Rivlin constitutive model and Rebar model, and the listrium and piston were simulated by rigid-body model. The nonlinear finite element analysis software ABAQUS was applied for computing the mechanical property of vehicle air spring. To further validate the reliability of the calculated results, the static characteristic test for measuring the mechanical property of air spring was carried out on electro-hydraulic servo experiment rig system of Instron 8800 air spring. The analysis indicates that these calculated results are in good agreement with the experimental results. Hence, nonlinear finite element method is an economical and practical approach to estimate mechanical property of vehicle air spring.