2015 Volume 56 Issue 5 Pages 455-462
The effect of the air flow, parallel to the home-made fabrics with various yarn densities, on the water vapor transfer coefficient (WVTC) has been investigated by simulated technique of the JIS ‘Water Method'. The WVTC value increased for the higher flow rate and decreased for the larger yarn density.
The water vapor permeation coefficient of the fabric (WVPCF), evaluated from the difference of the water vapor transfer resistances with and without the fabric, was linearly dependent on the square of the air flow rate. The tangent of the dependence, expressing the degree of the effect of the air flow rate on WVPCF, increased linearly for the porosity of the fabric higher than 19%, and was ignored for the lower. An experimental formula estimating the WVPCF from the parameters, the porosity of the fabric and the air flow rate, has been obtained for the fabrics.
