Finite element modelling and parametric analysis of vertical dynamic stiffness in sleeve-type single-chamber air springs

As a vital component of automotive suspension systems, air springs enable adaptive adjustment of stiffness and vehicle height, thereby balancing ride comfort, handling stability, and load-bearing capacity. However, accurately characterising their dynamic behaviour under transient excitation conditions remains a significant challenge in suspension system design. This study proposes a finite element model for predicting the dynamic stiffness of air springs. Frequency-domain viscoelastic parameters of the rubber material are identified through harmonic shear tests and incorporated into a finite element model by employing a hyperelastic–viscoelastic constitutive model. Experimental validation demonstrated high predictive accuracy, with the maximum deviation between simulated and measured dynamic stiffness remaining below 5.17%. Based on the validated model, a comprehensive parametric analysis quantified the influence of cord layer parameters (including angle, diameter, spacing, and position) on the air spring’s vertical dynamic stiffness. The results indicate that the sensitivity of these parameters follows the descending order: cord angle > cord diameter > cord position > cord spacing. This study provides theoretical foundations and simulation methodologies for optimising air spring design and enhancing the dynamic performance of advanced automotive suspension systems.