Computational models for predicting air permeability and thermal properties of polyester textile structures

This study develops pore-scale computational models to predict air permeability and thermal properties of one-layer, two-layer, and three-dimensional polyester textile structures. Accurate prediction of airflow and heat transfer in multilayer textile structures is essential for evaluating the thermal insulation and ventilation characteristics of protective clothing while ensuring thermal comfort. Compared with previous studies, the proposed pore-scale models examine the combined effects of multilayer textile structure and additional ventilation on airflow and heat transfer. The models were created in COMSOL Multiphysics 6.2 using Navier-Stokes and Brinkman equations for airflow and the energy equation for heat transfer simulations in the laminar flow regime. The results showed that when the complexity of textile structures increased from one-layer to three-dimensional structures, the air permeability decreased from 1257.1 mm/s to approximately 447.9 mm/s, and the thermal resistance increased from 0.0144 to 0.123 m 2 K/W. Additional ventilation improved heat extraction, achieving an effective heat transfer coefficient of 53.64 W/m 2 K at a flow rate of 0.5 dm 3 /min and an inlet air temperature of 10°C. The numerical predictions showed good agreement with experimental data reported in the literature, confirming the applicability of the developed models for the analysis of airflow and thermal characteristics of multilayer textile structures.