A THEORETICAL AND EXPERIMENTAL STUDY OF THE THERMAL INSULATION OF CLOTHING IN WINDY CONDITIONS

A theoretical model for the study of the thermal insulation of clothing in windy conditions is presented. In this model, the trunk of a human body is approximated to as an internally temperature‐controlled hollow cylinder. The clothing assembly covering on the cylindrical body consists of two parts, an outer wind resistant fabric and an inner porous fibrous material. The numerical solution derived agrees well with the experimental findings performed on a cylindrical togmeter in a wind tunnel. It appears that air penetration and changes in clothing geometry caused by compression, expansion or fluctuation of the assembly are two essential mechanisms which cause the wind‐induced reduction in thermal insulation. The effects of wind velocity, air permeability of the outer fabric and inner porous fibrous material, are examined and discussed.