The effect of PCM placement on torso cooling vest for an active human in hot environment

Abstract

The distribution of phase change material (PCM) packets on a cooling vest worn by active human in hot environments is investigated using an integrated fabric-PCM and bio-heat model. The model considered the effect of added PCM weight and hot environments on the human metabolic rate, and incorporated the effect of condensation to check its occurrence in the vest. The fabric-PCM model predictions of local torso skin temperature were validated experimentally on a thermal manikin operated at constant heat flux mode while its predictions of skin and core temperatures when integrated with the bioheat model were validated with published experimental data on human subjects exercising in hot conditions. The validated model is used in a parametric study to determine the best arrangement of 8 PCM packets distributed on different torso segments to improve sensation and comfort of human performing moderate activity in hot climate. It was found that placing 8 PCM packets on the back resulted in the best overall sensation of 1.38 as compared to 2.69 when no PCM is used using a sensation scale that varies from very cold at ?4 to very hot at +4.