An experimental investigation of stratification characteristic of fire smoke in the corridor under the effect of outdoor wind

Abstract

An investigation of previously established correlations between gas temperature distribution and smoke stratification in corridors and tunnels has been carried out. The investigated correlations are based on excess gas temperature ratios and Froude number scaling. A set of experiments were carried out in a scale-modelled “room-corridor” to investigate the stratification characteristic of smoke induced by fire and outdoor wind. The smoke flow pattern was visualized and the wind speed, the heat release rate and area of the window were investigated. The dimensionless parameter Froude number (Fr) was used to describe the stratification characteristics. The results show that when Fr ≤ 0.29, the smoke stratification is extremely strong; when 0.29 < Fr ≤ 0.58, the stratification intensity remains high and the smoke stratification is still strong; when 0.58˂Fr˂0.92, the stratification strength decreased significantly; when 0.92 ≤ Fr, the fire smoke mixed completely with the lower air and the smoke stratification failed. This can provide reference for the study of smoke stratification in corridor.