Dynamic Model of Facial Cooling

Abstract

Recent modifications to windchill forecasting have motivated the development of a rate-of-tissue-cooling model for the purpose of predicting facial cooling times. The model assumes a hollow cylindrical geometry with a fixed internal boundary temperature and adherence to the dimensions and tissue thermal properties of the cheek. Convective and radiative heat exchanges at the skin surface are also taken into account. The explicit finite-difference solution of the thermal conduction problem was applied to predict the transient temperature profile in the cheek model, composed of 25 concentric annular compartments with equally spaced nodes. Model predictions compare favorably to reported incidents of facial frostbite and to several laboratory studies on facial cooling. A sensitivity analysis demonstrates the effect of varying the values of tissue thermal resistance and cheek dimensions on the predicted facial cooling rate.