The Pressure Melting of Ice Under a Body With Flat Base

One of the anomalous thermodynamic properties of water is that the melting point of ice decreases as the pressure increases. This behavior was discovered independently by Kirchhoff and Thomson. It inspired Reynolds to speculate that the pressure-melting of ice and snow might be responsible for the low coefficient of friction experienced during skating and skiing. According to him, the pressure applied by the skate on the ice surface would cause superficial melting, which in turn would lubricate the relative motion between skate and ice. Although the pressure-melting phenomenon received some attention from early tribologists, this interest decreased after Bowden and Hughes' work, which showed that the superficial melting under the skate is due to friction (viscous dissipation) in the water film. In this note the authors consider a different fundamental aspect of the pressure-melting of ice, namely the indentation caused by a flat solid that is pressed against a block of ice. Unlike in the work referenced above, there is no lateral motion between the solid body and the ice block. The only motion that occurs is the normal progress that the solid body makes into the ice. This motion is made possible by the melting of the ice situatedmore » in front of the body. In this way, the pressure melting process is related to the contact melting process that occurs when a temperature difference ({Delta}T) is maintained between the solid body and the phase-change material.« less