Exergy analysis and thermoregulatory responses of the human body during walking in warm to hot thermal environments
摘要
Commuting in a warm to hot thermal environment induces thermal stress and exertion in humans, which can impact their health and productivity. In this study, we estimate the effect of such commuting on physiological thermoregulation through experimental and analytical studies. The experiments were administered in a controlled climate simulator with fifteen healthy adults. The variations in skin temperature (Tsk) measured at ten body parts, accompanied by subjective responses, were obtained for eight different temperatures (30–42°C) and two humidity (40–80%) set-points. We find that the variation in Tsk of different body parts decreases with an increase in air temperature. At higher temperatures, the mean Tsk increased with increasing relative humidity, while the effect was negligible at lower temperatures. The linear mixed-effects model is used to examine the sensation in terms of TSV, and it was found that, through likelihood ratio tests, the commute temperature has a considerable influence on TSV during walking, particularly in relation to humidity (p < 0.0001). Additionally, pairwise comparison is performed using the post-hoc LS-means test to determine which actual exposures differ significantly. An analytical model during walking is presented to demonstrate the different modes of heat transmission and exergy consumption. The effect of sensation of different conditions and evaporative cooling on exergy consumption is discussed.