Sensitivity analysis of tire-ice friction coefficient as affected by tire rubber compound properties

Abstract

Previous studies show that the material properties of the rubber are among the most important factors when designing a tire. In this study, we investigated the effects of different rubber properties on tire performance on ice. A theoretical model that incorporates these tire material properties was developed. The model was used to estimate the height of the water film generated due to friction and the friction coefficient for both, dry and wet regions at the tire-ice contact patch. After validating the results using experimentally collected data, the model was used to perform a sensitivity analysis on the tire performance with respect to six material properties of the tread rubber: thermal conductivity, rubber density, Young’s modulus, specific heat, roughness parameter of the rubber, and radii of spherical asperities of the rubber. To study the effect of each parameter, the desired material property was varied within a specific range while the other parameters were kept constant. The results from this study show the sensitivity of the magnitude of the friction coefficient to the rubber material properties. The friction coefficient has a direct relationship with the density of the rubber and has an inverse relationship with Young’s modulus, specific heat, and roughness parameter.