ABSTRACT
The digitization of the human body surface has found successful application in various scientific and industrial fields. In the field of protective clothing, this technology helped to select the right size of the clothing for individuals, reduce the number of sizes and stock of the clothing through anthropometric surveys, and optimize the clothing fit for males and females. On the other hand, a new opportunity for simulation of thermal effects in protective clothing emerged with a possibility to visualize and quantify the air layers within the ensemble that plays a crucial role for heat and mass transfer in clothing. Several studies have attempted to quantify the air layer distribution in a variety of garments, which found regional systematic trends in the distribution of air gap thickness and contact area in relation to the garment ease allowance and their consistency and homogeneity between various garment fits and types. This fact together with the observed low variability between 3D scanning repetitions despite complete redressing of the manikin indicated a high potential for a precise correlation model. Based on the database of 51 clothing pieces, an advanced regression model of air gap thickness was developed able to predict the distribution of the air gap thickness and the contact area parameters reliably for 14 body regions based on the ease allowances for the given body landmarks. Such a reliable and detailed model is crucial for mathematical models of heat and mass transfer in clothing to realistically predict thermal behaviour of the clothing system and its possible impact on human thermal and perceptual response. It was demonstrated for several selected scenarios, including different clothing fit levels, that the up-to-date assumptions and methods for determination of the air gap thickness can produce a substantial error for all whole-body, mean, and local physiological parameters, and hence, lead to false estimation of the resultant physiological state of the human body, thermal sensation, and comfort. Thus, the use of this detailed model shall contribute to the improvement of the simulation of human thermo-physiological and perceptual response to thermal environments in occupational settings and enhance the clothing design for protective and functional apparel to balance the environmental and bodily influence on clothing performance. This tool and the developed approach shall help researchers improve human thermal comfort, health, productivity, safety, and overall sense of well-being.
