Examination of the Static and Dynamic Damping Properties of Air Springs by Finite Element Method

Kasım H., Özkan E., Yazıcı M.

European Journal of Science and Technology (EJOSAT), no.25, pp.12-22, 2021 (Peer-Reviewed Journal)


In terms of vehicle dynamics, the suspension system must maintain good ride quality and handling performance against road irregularities, especially at high driving speeds. Air springs have been used in commercial vehicles and buses for many years to maintain ride height and increase vehicle comfort regardless of load. Due to the air springs' material structure, they are not subjected to unidirectional stresses during operation and exhibit non-linear behavior. The composite structure consists of four layers with cord fabric wrapped at opposite angles as two layers between inner and outer tires of different thickness. Therefore, the changes caused by loading alone are difficult to determine empirically. In this study, the static and dynamic damping properties of air springs, which are a part of the air suspension system, were investigated by both experimental and finite element methods. While determining the static and dynamic damping properties, the reaction force values formed in the air springs due to different pressure and displacement were used. Differences were observed in spring constants obtained from experimental and analytical studies during spring back after compression. After reaching the minimum height, a deviation of about 10% in the spring constant was observed when the backward movement started, and then a deviation of less than 6% was obtained. In experimental tests and analytical studies, it has been observed that the deflection values between the spring constants obtained as a result of instantaneous loading remain below 4% and that FEA analysis can be used effectively in air spring analysis.