A study and a design criterion for multilayer-structure in perspiration based infrared camouflage

Rather than resorting to extrinsic aids, like using additional heat insulation/storage or phase change materials or surface coatings as in other current infrared camouflage technologies, a new scheme of perspiration based infrared camouflage and a corresponding multi-layer cloth prototype were proposed recently by the present authors. In this paper, several experiments were conducted on a three-layer system based on the proposed prototype, and the original theories were modified to suit the experimental system. The experimental results compared well with the theoretical predictions in verifying the principle of proposed perspiration based infrared camouflage, and in examining the effects of such factors as layer thickness and layer sequence. More importantly, through a heat flux analysis, we found that the ratio of the latent heat flux to the sensible heat flux (ql/qs) can be used as a general criterion in designing the comfort performance of a cloth system. For the perspiration based infrared camouflage: the higher the ratio, the better the infrared camouflage effect.

► A multilayer cloth structure was proposed and examined for perspiration based infrared camouflage of human body. ► Several experiments were conducted to demonstrate and validate the feasibility. ► The influences of related important parameters were discussed. ► General criterion in designing comfort performance of a cloth system was established.