Effect of modeling sidewalls on tire vibration and noise

Low-noise tire design demands the potent model, which regards accessible parameters in the design process before manufacturing a tire. Unlike most previous analytical models that integrated tire treadband with sidewalls with an assumption of identical properties, this research segregates them. The separation clarifies the effects of each tire part on vibration and noise individually, which has not been presented in previous publications and is noteworthy in design. The model is developed considering three connected plates, describing treadband and sidewalls, on an elastic foundation derived from vibro-acoustic coupling inside the tire. Natural frequencies are determined by the Galerkin method using modes shapes satisfying all boundary conditions. The vibration response of a tire rolling on the road is then formulated utilizing Green's function and convolution integral. Eventually, vibrational tire noise is calculated by the boundary element method. Comparing the proposed model with the repeatedly used integrated plate model has indicated the dissimilarity of treadband and sidewall responses with a difference of 1.4 dB(A) in total noise level. Moreover, implemented parametric study based on a small central composite design has revealed their parameters' distinct influences on generated noise. For instance, increment in treadband thickness reduces sound level, while decreasing sidewall thickness effectively leads to noise reduction. So, the proposed model is worth employing instead of the previous overused integrated model to predict and reduce tire noise.