The effects of local cooling at different torso parts in improving body thermal comfort in hot indoor environments

The torso is the region of the body that generates the most heat, so local cooling is often applied to this region to improve thermal comfort of the human body. In this study, the local cooling at different torso parts including chest, abdomen, upper back, and lower back was applied to 20 subjects (10 males and 10 females) with low metabolic rate at 28 degrees C, 30 degrees C and 32 degrees C (while relative humidity maintained at 50% RH). The results show that the local cooling of the torso can significantly improve the overall thermal sensation and thermal comfort of the subjects in a hot environment. Among these four parts of the torso, cooling the upper back has the best effect, followed by lower back cooling and abdominal cooling. The effect of chest cooling is the worst, which is mainly reflected by the experimental results at 32 degrees C. The results of this study can not only be used to evaluate the potential of local cooling systems on torso parts but also to provide a design direction for cooling distribution in parts of the torso for wearable cooling garments. (C) 2019 Elsevier B.V. All rights reserved.