Research on Smoke Flow in a Tunnel Fire of Subway System

A three-dimensional mathematical model of the smoke movement in tunnel fires was established. Finite volume method was used to discretize the governing equations and the SIMPLE algorithm was employed to solve the governing equations. A scaling model (1:8) of the subway tunnel was built up based on similarity theory. Not only different positions of fire on the train, but also the different starting times of exhaust fan in the tunnel were considered. The disciplines of smoke temperature, smoke diffusion and wind velocity have then been compared under different the fire situations. The study is useful to analyze evacuating and controlling fire in emergent project of tunnel fire in a subway system.