Analytical model to study a new design concept for providing comfort in hot arid climate

Abstract

A special design of clothing based on ‘sombrero-effect’ by inclined wedge providing shadow on the base material has been proposed and investigated analytically in this study to improve the thermo-physiological comfort under dry and hot environment. The design involves small strips of opaque surface on the base fabric of the outerwear to provide tiny shadows at an inclination. The analysis of the heat and mass transfer in the proposed design enables numerical prediction of cooling heat flow at skin surface level. The predicted values are then compared with experimental data by simulating the conditions using a vertical skin model. The effects of certain material properties, particularly the colour of fabric and type of fibre have been studied and the role of the important design parameter, such as ‘shade angle’ or the angle of inclined strips has been investigated experimentally. It is observed that the analytical framework of heat and mass transfer in such a system is able to give useful results.