A tire–ice model (TIM) for traction estimation

• Structure and modules of the tire–ice model.
• Heat transfer module and simulation temperature rise in the contact patch.
• Validation of temperature rise in the tire–ice interface.
• Computation of friction levels in the contact patch.
• Validation of computed friction against measured friction.

Increased traffic safety levels are of highest importance, especially when driving on icy roads. Experimental investigations for a detailed understanding of pneumatic tire performance on ice are expensive and time consuming. The changing ambient and ice conditions make it challenging to maintain repeatable test conditions during a test program. This paper presents a tire–ice contact model (TIM) to simulate the friction levels between the tire and the ice surface. The main goal of this model is to predict the tire–ice friction based on the temperature rise in the contact patch. The temperature rise prediction in the contact patch is based on the pressure distribution in the contact patch and on the thermal properties of the tread compound and of the ice surface. The contact patch is next classified into wet and dry regions based on the ice surface temperature and temperature rise simulations. The principle of thermal balance is then applied to compute the friction level in the contact patch. The tire–ice contact model is validated by comparing friction levels from simulations and experimental findings. Friction levels at different conditions of load, inflation pressure, and ice temperatures have been simulated using the tire–ice contact model and compared to experimental findings.