Heat transfer in a cylinder sheathed by flame-resistant fabrics exposed to convective and radiant heat flux

A numerical model is developed which investigates heat transfer in a cylinder sheathed by flame-resistant fabrics when suddenly exposed to convective and radiant heat flux from simulated pre-flashover fire radiation. The column inside the cylinder system simulating the human body is assumed to keep at a constant temperature. This model incorporates characteristics of the heat-induced changes in flame-resistant fabrics and dry air thermo-physical properties. Temperature distribution was calculated with the help of a one-dimensional radial heat transfer model. A skin burn equation is quoted to predict second-degree skin burn injuries based on the numerical model. The effects of air gap thickness on mean incident heat flux to the skin simulant surface are also discussed. Results from the numerical model contribute to a better understanding of the heat transfer process within flame-resistant fibrous materials and fabrics in intensively high-temperature environment. At the same time, the method in the paper also helps to establish a systematic method for analyzing heat transfer in other cylindrical applications.