Calculation of the Three-Dimensional Free Surface Flow Around an Automobile Tire

Abstract

Abstract The 3D flow around a 195/65R15 automobile tire is calculated. To describe the free surface behavior with the usual conservation equations for mass and momentum, an additional equation for the water mass fraction is solved. For modeling the effects of turbulence, the well-known k,ε-model is used. The resulting fluid mechanics equation system is solved by a finite volume method. A finite element calculation considering inflation pressure and tire deflection gives the surface for the flow calculation. The goal is to determine the lift force of the tire at a certain velocity to predict the tendency of the tire to hydroplane. For a slick tire, the calculated pressure distribution in the water is presented. The lift and drag forces are evaluated from the pressure acting directly on the tire surface. The calculation is performed at three different velocities, 30, 60, and 90 km/h. A comparison with experimental data shows good agreement regarding the pressure distribution on the road in front of the tire.