Analysis of the Operation of Smoke Exhaust Ventilation in the Metro’s Technological Corridor Based on Numerical Simulation of Selected Locations of Fire

Abstract

The aim of the paper is to analyze the effectiveness of smoke exhaust ventilation for the protection of metro technical personnel. Therefore, the specified technological corridor as a part of the underground station was chosen. The Fire Dynamics Simulator (FDS) was used to carry out numerical simulations. Due to the low fire hazard, the heat release rate (HRR) was set at 1 MW after 250 s. Four cases were analyzed: three differing in the location of the fire source and a reference case in which the smoke exhaust ventilation is turned off. The analysis took into account temperature distributions and gas flow speeds, and qualitative verification of visibility. It was shown that the variant in which the fire source was located in the middle of the corridor turned out to be the most unfavorable variant in terms of the effectiveness of smoke exhaust ventilation. The operation of the smoke exhaust ventilation improved visibility, and reduced the temperature from 270 °C to 120–155 °C, depending on the variant, with local maximum flow speeds not exceeding 10 m/s. It was shown that properly designed smoke exhaust ventilation enables the evacuation of employees within the required safe evacuation time (RSET).