Modelling transient heat transfer through the skin and a contact material

Two thermal models of the skin and superficial tissues are described, both of which incorporate the thermal effects of subcutaneous and dermal blood flow through temperature-dependent heat sources. The model which represents the dermal blood flow as the perfusion of a region of finite thickness gives rise to purely numerical solutions for the transient temperatures. Representing the dermal blood flow by a heat generating surface gives rise to a model which yields explicitly analytical expressions. Although these analytical expressions require numerical integration techniques to finally evaluate them, they are of a form which allows temperature values to be derived more efficiently than by the purely numerical method. Both models are used to predict the time-dependent temperature profiles resulting from the interaction between the tissues and thermally passive materials in intimate contact with the skin surface. The predictions of the two models are compared and the limitations of the analytical model highlighted.