A Parametric Study of Air-Pumping Phenomenon in Tire Grooves Using Computational Fluid Dynamics

Abstract

The tire/road interaction process results in generation of noise, which is transmitted and audible in the inside and outside of the car. In the recent years, the structural-borne noise in a tire has been extensively studied. However, very few studies have been conducted on air-borne noise. Various studies and indoor experimental measurements suggest that among all air-borne tire noise mechanisms, air-pumping mechanisms, i.e. rapid displacement of air near the tire/road contact patch, is the dominant source of noise for certain tires and operating conditions. This research focuses on studying air-pumping mechanisms and uses a previously developed computational model to predict air-borne noise generated using a hybrid approach. The basis of the hybrid approach is a direct prediction of near-field solution using compressible Navier-Stokes equations with turbulence modeling, combined with an analytical prediction of far-field acoustics using an acoustic model. Only the near-field acoustic characteristics are discussed in this paper. The tire rotation and groove deformations at the tire/road contact is modeled through mesh motion and prescribed deformation functions, thereby circumventing the need for coupling with a structural solver for fluid-structure interactions. The capability of the developed computational model in estimating the tire noise is shown and the effects of varying different parameters such as tire speed and geometry on the evolution of the estimated responses at various near-field receiver locations are studied.