Temperature in a twin-disc wheel/rail contact simulation

Temperature in a machine element contact is critical in determining wear mechanisms and the conditions at which wear transitions occur. Calculations have shown that the temperature in a wheel/rail contact under severe contact conditions may lead to a transition from severe wear to catastrophic wear. Such high lateral loads and slips can occur in wheel flange contact at railway track curves. The aim of this work was to use a thermal camera to measure the temperatures in a twin-disc simulation of a wheel/rail contact. Disc body and contact temperatures were studied for a number of different contact conditions. Disc emissivity values were determined using an independent calibration test. Measured temperatures were compared with those derived using analytical models which equate frictional heat generated in the contact with heat dissipation due to conduction, convection and radiation. Good correlation was found between the experimental and analytical results. This is despite the fact that its emissivity values were assumed constant throughout the test.