Investigating heat generation and transfer in hygroscopic and exothermic textiles by 3D numerical model

Abstract

Due to the complex heat generation and transfer in the hygroscopic and exothermic textiles, the deep understanding of thermal regulating performance is still blur. In present manuscript, we developed a computational fluid dynamics (CFD) model based on weave structures in textile to investigate hygroscopic thermal generation and transfer phenomenon. The temperature changes were monitored when the textiles absorbed moisture from the surrounding atmosphere. We validated the proposed model by comparing the experimental and simulated data, with a strong correlation (above 0.938) and minimal discrepancies in temperature. Extensive parametric study was further conducted to clarify the hygroscopic heating performance and heat transfer characteristics. The simulation data revealed that higher areal density commonly resulted in greater moisture absorption and consequently increased heat generation. Moreover, enhanced thermal insulation can impede the heat transfer from the sample's interior to its surroundings, thereby facilitating hygroscopic heat accumulation and temperature increase in the sample. Additionally, the simulation under different ambient temperatures demonstrated that higher environmental temperatures led to more pronounced warming effects. Since the diminished temperature gradient could reduce heat dissipation through thermal radiation and convection between the sample and ambient environment.