Modelling fire size and spread in tunnels

Abstract

The heat release rate (HRR) of a fire in a tunnel is a crucial factor, both in terms of fire spread and smoke production. Key factors which influence the HRR are: {1} the nature of the burning item, {2} the tunnel geometry, {3} the ventilation conditions and {4} vehicle separation. This paper reports on work which has been undertaken over a number of years to model the dependence of HRR on these factors; the work is continuing. Specifically, Bayesian probabilistic models have been devised to model the dependence of the HRR of a fire on tunnel geometry and longitudinal forced ventilation and deterministic models have been devised to model fire spread from one item to another in a tunnel similar to the Channel Tunnel; again with longitudinal ventilation. Key interim results are presented. Copyright © 2005 International Association for Fire Safety Science.