An improved structural-acoustic coupling model for tire cavity noise

Tire acoustic cavity resonance inside the tire-wheel assembly causes a tonal noise typically in the range of 190â–“250 Hz, which is an important source of vehicle interior noise. An analytical model considering cavity resonance is required for noise and vibration reduction; however, existing models require improvements, such as the consideration of composite properties and sidewall elasticity of the rubber-based tire. A new analytical tire model incorporating cavity resonance is proposed in this work. The tire is modeled as an annular cylindrical shell made of composites with elastic foundations rather than the typical isotropic shell with rigid simply supported boundary conditions. A unified numerical method with all nine sets of possible solutions for the vibration characteristic equation is applied to avoid missing solutions in conventional practices, as no available analytical solution for the problem exists. Modal results obtained through this model are in satisfactory agreement with the experiment, generally with less than 10% error. It is found that frequency response functions (FRFs) match with experiments basically. The effects of cavity resonance on the spindle force and moment were also very pronounced, through which the level of tire cavity noise can be reflected. While FRFs show peak values in both first and second cavity modes, the force response at the spindle has no apparent peak around the second tire cavity resonance, confirming the previous findings. The proposed model provides a sound theoretical formulation for tire cavity resonance and will also be an efficient quantitative tool for tire noise and vibration reduction.