CONVECTIVE HEAT TRANSFER COEFFICIENTS AND CLOTHING INSULATIONS FOR PARTS OF THE CLOTHED HUMAN BODY UNDER CALM CONDITIONS

Abstract

Convective heat transfer coefficients for each part of the clothed human body were evaluated under airflow conditions and compared to those of nude body. This was done by measuring clothing surface temperatures on seated and standing manikin using an infrared-imaging radiometer. The convective heat transfer coefficients for the clothed manikin were larger than for the nude manikin. The difference could be 100 to 200% for some individual parts, and for the overall body the difference was 30 to 50%. These results were consistent for both standing and sitting postures, or for facing upwind and facing downstream, although slightly larger differences between clothed and nude could be seen when the manikin was sitting and facing upwind than in the other conditions. Clothing insulation for each part was also estimated. Some differences between standing and sitting were observed at the body part level. However for the whole body the difference was small. Regression models for convective heat transfer coefficients and clothing insulation for all bod y parts were presented for use in human thermal modelling.