Investigation Of Fire-Induced Smoke Movement In Tunnels And Stations: An Application To The Paris Metro

Abstract

The behaviour of fire-induced smoke layers in a tunnel and a particular station of the Paris Metro, in the presence of ventilating-air flow, is experimentally investigated using small scale models. For practical purposes, laser investigation techniques are utilized. The reverse layer formed near the ceiling of a tunnel, and flowing against the ventilation, is analyzed from the results of the small scale test as a function of the fire source power and ventilation current. A simple modelling procedure is applied which should permit full scale lengths of reverse layers to be deduced. Measurements of temperature di s t.r i bution, along the tunnel median plane and cross sections, reveal the stratified evolution of the smoke backflow. The experiments with a ventilated tunnelstation configuration show the essential characteristics of the smoke movement (entrainment, stratification, recirculation, etc ... ). The propagation of hot combustion products, indeed, is of practical importance for fire-fighting and people evacuation.