Abstract:

In order to investigate the moisture transfer characteristics of moisture in fabrics in low-level radiant heat exposures, the evaporation process of moisture in fabrics and the influence of moisture evaporatio on the thermal insulation performance of fabrics were analyzed by using drying theoretical method and thermal infrared imager. The results indicate that the drying process of fabric can be divided into three stages: the initial heating stage, in which drying velocity and the temperature increase rapidly and the moisture content decreased slowly; the intermediate stage, in which the drying velocity keeps stable and the temperature increased slowly, while the moisture content decreases rapidly; and the final stage, in which the drying velocity slows down and the moisture content decreases slowly. The fabrics with higher moisture has better thermal insulation performance, but when the moisture content is lower than 20%, the thermal insulation performance decreases rapidly, causing rapid increase of the surface temperature of the fabric surface. The migration of moisture in fabrics was analyzed by fitting data such as moisture drying velocity, three classic drying kinetics models including Page, Newton and Henderson were adopted to analyze the migration of moisture in fabrics. The results show that the dynamic drying process of fabrics in low-level radiant heat exposures can be described mathematically by Page equation.

Key words: porous fabric, thermal radiation environment, moisture transfer, drying kinetics, thermal insulation