Polymer Testing (Nov 2023)
A new approach to demonstrate the exothermic behavior of textiles by using a thermal manikin: Correction methods of manikin model
Abstract
In high humidity environments, certain textile fibers, such as wool, viscose, cotton, and polyester, demonstrate a tendency for exothermic heat generation. Utilizing a comprehensive thermal manikin model, this study sought to examine the intricate heat flux patterns across the manikin's torso post an 1800-s transition under fluctuating humidity levels, ranging from 35% to 80%. Initial findings highlighted a dichotomy: some segments exhibited a marked decrease in heat, subsequently recovering, whereas others showed a rapid escalation. Notably, to maintain a skin temperature of 35 °C on the manikin, there was a transient heat reduction in select segments, emphasizing the pivotal role textiles play in ensuring thermal comfort during transient conditions. The research incorporated two distinct data correction methodologies: the first calibrated heat flux measurements based on steady-state values pre and post humidity alteration, and the second drew upon a consistent reference segment, such as the head, which remained unaffected by the fabric. Intriguingly, these heat flux behaviors correlate directly with a fabric's moisture buffering capability, with wool emerging as the most adept, showcasing a buffering efficiency 26%, 45%, and 96% superior to viscose, cotton, and polyester, respectively. Furthermore, the microclimate—a critical layer between garment and skin—plays a determinant role, with wool's microclimate witnessing a sharp 58% surge when external humidity reached 80% after the stipulated transition period. This investigation highlights the unique thermal insulation properties of wool in varying humidity contexts, providing a strong basis for future scholarly investigations into the intricate thermal characteristics of textiles.
