Experimental investigation into the effect of macroscopic cross-country ski parameters on gliding friction

The complexity of the load response on a modern cross-country ski makes it difficult to address the individual macroscopic parameters' influence on ski-snow friction. In this study, a custom adjustable ski was developed to isolate the effect of normal force, apparent contact area, spacing and load split on the coefficient of friction. These parameters were tested in a ski-snow tribometer at relevant sliding speeds, normal loads, slider sizes and snow conditions for cross-country skiing. At cold air temperatures (−10 °C) the friction was governed by the average contact pressure, whereas at warmer air temperatures (−2 °C and + 5 °C) the friction was governed by the apparent contact area. Additionally, the effect of load split between the front and rear slider showed different trends depending on the temperature. Smaller spacing between the two sliders led to reduced friction across all temperatures. These findings provide new insights for optimizing cross-country ski gliding performance in various snow conditions.