An Investigation On The Total And Local Clothing Thermal Insulation And Air Gap Of Fourty Sets Of Chinese Male Ethnic Minority Costumes

Clothing thermal insulation and microclimatic air gap are the two most important thermo-physical parameters to determine thermal comfort. Previous documented studies were mainly focused on western clothing and overall clothing heat transfer properties, a limited number of studies have been made on local clothing heat transfer properties as well as Chinese ethnic minority costumes. Hence, there is an urgent need to study both the overall and local heat transfer properties of Chinese ethnic costumes. In this study, the total and local thermal insulation of 40 sets of Chinese male ethnical costumes were determined on a 34-segment ?Newton? thermal manikin. The overall and local clothing surface area, the clothing air gap thickness and the clothing microclimatic air volume were measured and analyzed by a contactless three-dimensional(3D) body scanner and the commercial Geomagic software(3D Systems Inc., Rock Hill, South Carolina). Besides, relationships between the clothing thermal insulation and air gaps for the whole body and local body parts were investigated. The correlations between the overall/local clothing area factors and the overall/local clothing intrinsic thermal insulation were also explored.The results presented in this thesis have reconfirmed that the clothing thermal insulation is largely affected by such clothing physical properties and design features as the clothing structures, layer distributions, the way of wearing, fabric thickness, clothing weight, and the clothing microclimatic air gap. Results also demonstrated that the clothing total thermal insulation first increased with the increasing air gap thickness/air volume, followed by a continuous decrease when the average air gap thickness and the total air volume exceeded 39.6 mm and 68.7 dm3 respectively(i.e., a parabolic trend). Similarly, it was also found that parabolic relationships between the local thermal insulation and the local air gap were observed at each studied body part. In addition, the slope of the newly developed linear equation to quantify the relation between the clothing area factor and the intrinsic thermal insulation of Chinese ethnic costumes was much greater than that of the published equation established for western clothing. This was mainly because Chinese Costumes had a much looser fitting compared to western clothing. This thesis work provides a comprehensive database for future studies with regard to human local thermal comfort of Chinese male ethnic minority groups.