Finite element analysis of the heat transfer in footwear

This paper outlines the use of finite element analysis to describe the heat transfer in footwear. Experiments were conducted to determine the temperature distribution in footwear with a variety of environmental temperature and footwear properties considered. Finite element models describing the heat transfer between the foot, sock and shoe are presented with the conductivity, specific heat and density properties of each material presented taken from literature. Based on foot geometry obtained from plaster casts, these models predicted temperatures within footwear with conduction, convection and radiation taken into account. Results from the models were compared with experimental findings with generally good agreement; however the models were limited by a simplified heat input value based on whole body values which did not account for the counter current heat exchange and also by the absence of evaporation as a mode of heat transfer which was significant in hotter conditions. A sensitivity analysis on the heat transfer models showed that the major contributors to the in-shoe conditions under dry heat transfer were the ambient temperature and the initial temperatures of the foot, while the heat flux and sock conductivity also had a minor affect. Further studies are required to include the effects of evaporation and to include the counter current heat exchange as a control for heat input to the foot.