INVESTIGATION ON THE MODELING OF TIRE ROTATING USING COMPUTATIONAL FLUID DYNAMICS

Fuel efficiency is very important when designing new vehicles. There is a continuous demand for lower fuel cost to customers. Many researchers have started to investigate the aerodynamics of tires. Since the experimental approaches are time consuming and costly, numerical methods have been developed to model the air flow around the tire. One of the challenges for modeling the tire is rotating boundary and contact patch. In the CFD model, both rotating and tire deformation have to be considered to get accurate predictions. However, most of the current methods neglect the tire deformation and contact patch. Therefore, in this study, three modeling approaches are compared for the modeling of tire rotation. They include rotating wall, multiple reference frame and sliding mesh. In CFD simulation, another challenge is mesh generation due to the sharp edge and large curvature around the contact patch. In order to generate mesh efficiently. A hybrid mesh which combines hex elements and polyhedral elements is used in this study. In addition, three different tire designs are investigated, including smooth tire, smooth tire with grooves and grooved tire with open rim. The results show that tire with open rim has the highest drag. Sliding mesh provides the most accurate predictions regarding of aerodynamic drag.