Simulating and Analyzing the Effect of Garment Fitness on Human Body Heat Transfer

Garment fitness is influenced by garment pattern, human body shape, garment size and fabric drape. To investigate the effect of garment fitness on human body heat transfer, six different sized men´s shirts with increasing chest circumference from 91cm to 111cm are tested. A thermal manikin with adjustable joint is used to test the thermal insulations and an infrared thermal camera is used to quantify outer surface temperatures of six garments. The PMV and PPD values are calculated when people dressed six garments in different sizes standing in an environment of temperature 20 ±± 2°C, relative humidity 50 ±± 5% and air velocity 0.2 m/s. Although the air gap thickness increases with garment size, the thermal insulations of six garments are not linear growth. Experimental garment with chest circumference 99cm has the highest thermal insulation and the lowest outer surface temperature in six garments. Based on a comprehensive analysis of garment fitness and PMV value, the garment with chest circumference 95cm seems to have the best thermal comfort in six experimental garments. A numerical model is established to forecast the effect of air gap thickness on garment surface temperature.