Numerical Investigation of Thermal Insulation Performance in Air‐Based Textile Based on Fluid Dynamics

ABSTRACT Human thermoregulation entails the dynamic physiological management of heat generation, transfer, storage, and dissipation to maintain temperature stability across diverse environmental conditions. This study systematically investigates the effects of air layer thickness, airbag configuration, fabric emissivity, and the wrapped types on gas flow velocity and temperature distribution by constructing airbag structures. Based on fluid mechanics principles, a hierarchical six‐airbag layered air‐based textile design was proposed and analyzed using CFD‐Fluent multiphasic coupling simulations to quantify thermal insulation behaviors. Experimental validation via infrared thermography (IRT) demonstrated a 0.97 correlation coefficient between simulated and measured surface temperatures, confirming model reliability. Key findings reveal a triadic regulatory mechanism of static air proportion, convective intensity, and radiation reflection, demonstrating that a 2 cm air layer thickness optimizes thermal resistance through dynamic equilibrium between convective intensity and conductive losses. It shows a 10.5% reduction in surface temperature for the 12‐airbag wrapped sample compared to the four‐airbag counterpart, while silver‐coated fabrics exhibit 11.8% lower surface temperatures under radiation heat exposure, validating the radiative insulation potential of metal coatings. These insights establish a robust theoretical foundation for thermal management in dynamic deformation environments and provide critical design guidelines for lightweight, high‐performance equipment.