3d Numerical Investigation on Heat Transfer and Fluid Motion within Air Thermoregulatory Clothing

Abstract

In this study, we developed an air thermoregulatory clothing, and evaluated its thermal regulating performance using thermal manikin in a climate chamber. Additionally, a three-dimensional model considering the multi-chamber configurations and complex curved geometries was constructed, which was validated by comparing experimental and simulated data. Detailed simulations were further conducted to delineate the air flow pattern, temperature profiles and heat flux, thereby elucidating the thermoregulatory performance under different chamber thicknesses and ambient temperatures. The thermal insulation of air thermoregulatory clothing significantly increased by 90.3% when its thickness ranged from 2.5 mm to 15.0 mm. The simulated airflow pattern and temperature distribution suggested that the convective and radiative heat transfer became more drastic once the thickness exceeded 15.0 mm, which can be attributed to the absence of hindrance from fiber's porous structure. In addition, lower environmental temperature led to accelerated flow motion within the air chamber, thereby increasing convective heat dissipation. Utilizing thermal comfort and energy-saving models, the air thermoregulatory clothing was demonstrated to extend thermal comfort zone (range from 23.21°C to 28.45°C) by 63%, while simultaneously reducing heating energy consumption by 17.8% and cooling energy consumption by 24.6% in air conditioning system compared to conventional clothing.

Keywords: Air thermoregulatory clothing, Thermal regulating performance, Numerical simulation, Ambient temperature, Thermal comfort