Thermal imaging on the force transmission of tires on winter tracks under laboratory conditions

For the analyses of the influence of friction heat on the transmission of tangential forces of a tire with and one without sipes on ice and snow, tire's longitudinal force characteristic and its surface temperature have been measured on the inner drum test bench at the KIT. The analysis of the instationary heat flux shows, that the thermal force limit wherein friction forces can be transmitted without melting is close to tires force characteristic. The comparison of resulting friction heat flux with the transmitted mechanical power shows that with increase of track hardness the force closure part of tangential forces increases, while sipes lead to an increase of the form closure part.