Measurement of temperature and humidity gradient across underwear for optimal microclimate regulation of multi-layered clothing systems

Temperature and moisture gradients in the dynamic mode have been investigated using a skin model but not thoroughly with the thermal manikin. Even though thermal manikins have been developed for dry and wet thermal transfer in a steady state, information on the dynamic distribution of the moisture across the clothing layers worn on a sweating manikin would be very helpful to develop more comfortable protective clothing and to advise the wearer how to wear underwear under the protective outer shell. The objectives of this paper are firstly, to obtain temperature and moisture gradients across multiple layers using a sweating thermal manikin by careful experimental procedures and secondly, to find out the most comfortable arrangement of underwear layers under a Gore-Tex outer jacket. Also, to compare the effects of hygroscopic and hydrophobic meshes as innermost underwear compared to ordinary cotton and nylon interlock underwear, on the various aspects of heat and moisture transfer, i.e. total vs. local, as well as steady vs. transient states. Optimized arrangement of clothing layers has been discussed for the multi-layered system based on the results of the dry and wet test using the thermal manikin and the temperature and moisture gradients across fabric layers. Interestingly, the microclimate of the polyester mesh/nylon combination (MpN) is not drier, even when the wet thermal resistance of MpN is smaller. The results indicate that it was not possible to assess the wear comfort of the clothing ensemble based upon the information on dry or wet thermal insulation alone.