A comparison of the water vapor transport through fabrics under conventional and subzero climate

Although much study has been dedicated to heat and water vapor transport through fabrics, there remains a great lack of understanding on water vapor transport through fabrics under subzero climate, particularly in terms of the effect of condensation on water vapor transport. In this paper, we report on a novel apparatus, which was used to measure the moisture transport through fabrics under a conventional (20 degrees C) and subzero (-20 degrees C) climatic condition. Experimental results showed that, under both conventional (20 degrees C) and subzero (-20 degrees C) climate, the accumulation of condensates on fabric surfaces increased linearly with time and the rate of moisture transfer through fabrics was little affected by the accumulation of condensates on fabric surfaces. Nevertheless, the water evaporation from the water bath, condensation on fabric surface and vapor transmission through the fabric was greater and the moisture vapor resistaree smaller under the subzero (-20 degrees C) climate than those under the conventional (20 degrees C) climate.