MASS AND HEAT TRANSFER MEASUREMENTS THROUGH TEXTILES LAYERS MESURES DES TRANSFERTS DE MASSE ET DE CHALEUR A TRAVERS LES TEXTILES

摘要

The physical properties of textile materials which contribute to physiological comfort involve a complex combination of heat and mass transfer. Each may occur separately or simultaneously. They are time dependent and may be considered in steady-state or transient conditions. Thermal resistance is the net result of the combination of radiant, conductive and convective heat transfer ant its value depends on the contribution of each to the total heat transfer. Although it is an intrinsic property of the material, its measured value may change through the conditions of test due to the interaction of components such as radiant heat transfer with the surroundings. Several methods exist which may be used to measure heat and moisture properties, each of which is specific to one or the other and relies on certain assumptions of its interpretation.