Abstract
Insulation of clothing has a great influence on the thermal characteristics of a human body. Examination of the influence takes an important role in improving thermal comfort and energy consumption of air conditioners. Our report describes the experimental study of insulation effect of clothing for thermal characteristics of a human body in its segments. The experiments were performed using one young male subject in a climate chamber. The physiological tests were conducted on the sitting subject dressed in 0.17clo and 0.57clo. The environmental conditions in the present experiments were: chamber air temperature≒28℃, mean radiant temperature is approximately equal to chamber air temperature, relative humidity≒52%, and air relocity≒0.15m/s (still air movement). The measuring items were: skin temperatures, heat flux from skin surfaces, local air velocities near skin surfaces, and temperatures and relative humidities within the clothing at selected segments of the body (Hardy-DuBois' twelve sites). The results obtained from the present study are as follows: 1. as the insulation of the clothing increases, 1) the increase of skin temperatures appears clearly in the peripheral segments of body, such as shin, calf, and instep. 2) the decrease of heat flux from skin surfaces appears significantly in the trunk segments of body, such as chest and abdomen. 3) the increase of temperatures within the clothing becomes clearly in the peripheral segments of body, such as shin, calf, and instep. Further the increase of absolute humidities within the clothing appears clearly in chest, abdomen, and instep. 2. assuming that the activity level is 1.0met, the calculated results of the average skin temperature and the heat flux from the whole skin surface using the experimental results agree qualitatively with the theoretical results obtained from the 2-node model developed by Gagge et al. However, as the insulation of the clothing increases, the experimental result about the increase of the average skin temperature exceeds the theoretical result by about 0.4℃. And the experimental result of the heat flux from the whole skin surface exceeds the theoretical result by about 30%.
