Determining the Optimum Size Combination of Three-Layered Cold Protective Clothing in Varying Wind Conditions and Walking Speeds: Thermal Manikin and 3D Body Scanner Study

Abstract

Garment fit and still air between clothing layers affect heat transfer through the clothing and thus the thermal insulation. Wind and body movement decreases clothing insulation by causing ventilation inside the clothing and by compressing air layers. The objective was to find the optimum size combination of three-layered clothing at two different wind speeds, and in stationary and walking situations, and to evaluate the effect of the wind direction on thermal insulation and air gaps inside the clothing. The clothing ensembles consisted of three layers (base, mid, outermost layer) in twelve different size combinations. The thermal insulation of the ensembles were measured in a climatic chamber (ambient temperature 10 °C, wind speed 0.3 m/s and 8 m/s) using both a static and moving thermal manikin. Whole body and cross-sectional figures of each clothing layer were taken by a 3D body scanner. The results showed that in calm conditions, static total thermal insulation was higher when the mid- and outermost layers were larger in size. When air movement was added by wind and body movement, thermal insulation reached its highest value when the outermost layer was one size larger than recommended in EN 13402-3.