Frictional heat generated by sweeping in curling and its effect on ice friction

In the sport of curling, players sweep the ice in the front of curling stones to increase the distance that the projectiles slide. Their vigorous sweeping raises the surface temperature of the ice, thereby reducing its coefficient of friction. The change in ice temperature is dependent on the velocity that curlers sweep the ice, the downward force they apply, and the pattern that is swept. The forces and velocities applied by Olympic level curlers were recorded with an instrumented brush. Laboratory-based rubbing experiments were conducted to determine the temperature rise in ice from sweeping. A numerical model was developed on the basis of the recorded sweeping profiles and laboratory-based rubbing experiments. The model was used to compare the thermal effects of two popular sweeping styles and shows that a conventional low attack angle style is the most efficient.