Citation

Fletcher DF, Kent JH, Apte VB, Green AR. Fire Safety J. 1994; 23(3): 305-325.

Copyright

(Copyright © 1994, Elsevier Publishing)

DOI

unavailable

PMID

unavailable

Abstract

The calculation of the consequences of fire occurring in a tunnel requires a predictive model that can calculate smoke concentrations, temperatures and radiation heat fluxes. In this paper, results from a field model developed at the University of Sydney are compared with data obtained from experiments on pool fires in a ventilated tunnel. The model solves conservation equations for mass, momentum and energy, together with those for the k-[var epsilon] turbulence model. Combustion is modelled assuming that the chemistry is fast compared with the mixing, by solving equations for the mixture fraction and its variance. Radiant heat exchange between the gas, soot and walls is modelled using the discrete transfer method. The calculations have highlighted a number of interesting features of the flow behaviour and modelling sensitivities. In particular, a study of the effect of the turbulence modelling and soot radiation modelling on the predicted temperature stratification and smoke backflow has been performed. Comparison of the calculated temperature fields and flame shapes with the experimental data has shown good agreement and has quantified the sensitivity of the predicted results to these important modelling parameters. This study highlights the utility of field modelling for the analysis of fires and smoke movement in tunnels.