Development of an instrument to study thermal resistance of fabrics

Abstract

An instrument has been developed to measure thermal resistance of fabrics under steady state condition using guarded hot plate method. This instrument can be used to test a given fabric in absolute method as well as comparator method under convective or non-convective measurement conditions. It is observed that the instrument gives repeatable results up to two decimal places of thermal resistance value. Effect of change in ambient temperature and rest plate temperature has also been studied and it is found that there is no significant change in measured thermal resistane of the fabric within the range of room temperature and test plate temperature used. The study on the effect of wind speed on the thermal resistance of woven fabrics shows that the thermal resistance reduces with the increase in wind speed.