A Simple Radiation Heat Transfer Model for Prediction of Fire Growth

Abstract

Flame spread over solid fuel in room fires is strongly influenced by heat transfer to fuel surfaces. Adequate modeling of heat transfer is essential for zone model to predict fire growth with reasonable accuracy. Experiments and numerical analysis have demonstrated that thermal radiation from soot formed in the combustion process contributes significantly to the total radiant heat flux. A simple radiation heat transfer model which takes into account the enhancement of radiation by soot was implemented in a fire growth model. The gas-soot mixture is approximated as a grey body and its emissivity is calculated with a grey expression. This paper presents a discussion of the simplified radiation model and reports the use of the NRCC model to predict fire growth of flaming and flashover types. Comparisons are made between the experimental results and the model predictions.