Numerical Study of the Effect of a Natural Convective Boundary Layer around the Human Body on the Transfer of Heat through a Textile Structure

Abstract

Heat losses from the human body occur through a barrier of one or more textile layers with particular permeability, thermal insulation, water absorption abilities, etc. The convective boundary layer (CBL) around the clothed body is disturbed during body movement, and the air layer between the body and the textile layer(s) is broken up, thus changing the heat transfer through the textile layer and its insulation abilities. The purpose of the present study was to evaluate the effect of the convective boundary layer around the human body on the heat transfer through a textile layer by numerical simulation, using Computational Fluid Dynamics and a commercial CFD software package, by means of the Finite Volume Method. A new approach for modeling a textile surface was applied based on the theory of jet systems. The results of the study indicated that heat transfer trough the textile barrier is strongly influenced by the speed of the convective layer around the human body and the textile layer placed in between the body and the environment.

Study of Multilayer Clothing Thermal Insulation Using Thermography and the Finite Volume Method

“…A new approach of presenting a numerical model of a textile surface transmitting heat by convection to the surroundings was presented. CFD simulations were used to study the influence of the speed of CBL and its size on the ability of the textile structure to transfer heat in the throughthickness direction of the sample [11].…”