Elastic wave manipulation in suspension helical spring: Mechanisms and control strategies for tire acoustic cavity resonance noise mitigation

Developing helical springs that effectively suppress road noise without compromising the vehicle dynamics, particularly handling stability and ride comfort, poses a critical engineering challenge. To address tire acoustic cavity resonance (TACR) noise, a primary peak contribution of structure-borne road noise (SBRN), minimal structural modification strategies to control SBRN with micro-amplitude vibration are proposed. This paper provides unique elastic wave propagation models for helically symmetric beams to support the physical insight into vibration response. Comparative analysis of wave behavior shows that low-order quasi-propagating waves with high negative group velocity (NGV) exhibit omnidirectional and localized propagation characteristics. The scattering attenuation of these waves, resulting from geometric folding in helical configurations, demonstrates pronounced parametric dependencies on key spring geometry. Specifically, reducing wire diameter and increasing helix radius can enhance the attenuation band and attenuation of NGV quasi-propagating waves, while optimizing spring inclination angle may expand the primary vibration zone, thereby reducing the end vibration output. The low-level resonance and high tunability of these waves have resonance sidebands with high matching with the TACR band. Furthermore, damping optimization strategies of widely applicable wave mode matching and spatially advantageous response matching significantly improve vibration suppression. Overall, this work establishes a comprehensive dynamic design framework for helical springs that integrates numerical methods, elastic wave manipulation mechanisms, vibration optimization strategies, and experimental verification, offering scientific guidance for medium–low frequency TACR noise mitigation.