Conductive Heat Transfer Prediction of Plain Socks in Wet State

Abstract

In this study, an algebraic model and its experimental verification was carried out to investigate the effect of moisture content on the heat loss that takes place due to conduction of sock fabrics. The results show that increasing moisture content in the studied socks caused a significant increase in their conductive heat loss. Plain knitted socks with different fiber composition were wetted to a saturated level, and then their moisture content was reduced stepwise. When achieving the required moisture content, the socks samples were characterized by the Alambeta testing instrument for heat transfer. Three different existing modified mathematical models for the thermal conductivity of wet fabrics were used for predicting thermal resistance of socks under wet conditions. The results from both ways are in very good agreement for all the socks at a 95% confidence level. In the above-mentioned models, the prediction of thermal resistance presents newly a combined effect of the real filling coefficient and thermal conductivity of the so-called “wet” polymers instead of dry polymers. With these modifications, the used models predicted the thermal resistance at different moisture levels. Predicted thermal resistance is converted into heat transfer (due to conduction) with a significantly high coefficient of correlation.

The effect of weft yarn type and elastomer yarn threading on the properties of elastic warp knitted fabrics. Part II: Thermal comfort properties

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“…At a 95% confidence level, the results from both methods agree quite well for all of the socks. (Mansoor et al, 2021) Gao et al (2022 studied the influence of external temperature (20°C-45°C) and relative humidity (25%-85% RH) on evaporative heat loss through firefighter turnout materials using a sweating guarded hotplate. Four firefighter turnout composites were chosen, each comprising three different bi-component (semi-permeable) moisture barriers and one microporous moisture barrier.…”

“…The influence of moisture content on the heat loss that occurs owing to conduction of sock textiles was investigated by Mansoor et al (2021) using an algebraic model and its experimental verification. The findings demonstrate that as the moisture level of the socks investigated increased, so did their conductive heat loss.…”

“…At a 95% confidence level, the results from both methods agree quite well for all of the socks. (Mansoor et al , 2021)…”