Effects of ski warming on ski-snow friction: some preliminary results

Some experiments have been performed to determine the effect on the friction coefficient of a little temperature increase caused by a small electrical resistance inserted in different ways in a ski or a ski-like device. It appears that at low speed this warming is able to reduce significantly the friction coefficient. The conditions of the experiments cover only reduced speed and temperature intervals. A possible interpretation of this phenomenon is based on the modification of the quasi-liquid-layer existing on the surface of snow at temperatures higher than -30 degrees C. A wider set of parameter conditions should be analysed to confirm this interpretation.