Study On Smoke Flow And Personnel Evacuation Simulation In Subway Station Fire

As a modern rail transport vehicle ease urban traffic congestion in the city,the railway not only decreases city contamination?reduces energy consumption,and also promotes the economic development of the city simultaneously.But for the subway belongs to the underground buildings,compared with ground buildings,the subway features in narrow and comparatively close.In case of fire in subway station,therefore,large people injuring and property loss will be caused.For the past few years,because of various reasons caused the subway fire accident in foreign and domestic that alarm us.Therefore,there is a great practical significance for study the smoke movements and personnel evacuation in subway fire accident.Based on the Hefei subway station,the thesis primarily studies the smoke spread law and personnel evacuation in different cases.Based on computational fluid dynamics(CFD)and large eddy simulation(LES),establishes mathematical and physical model of the subway station by using Pyrosim software,and sets up three different fire location,where is on the left side of the 10 m platform,middle the stairs(on the left side of the 60 m)on the platform and when the train in the station in the middle of carriage respectively,and in accordance with the relevant literature sets up different fire heat release rate(HRR,including platform fire HRR is 2.5 MW,train fire HRR is 5 MW),studies fire scenarios in different ventilation and smoke exhaust mode,and gets the rules of smoke spread in subway station and temperature and visibility distribution on the platform of eye location and the feature 2m height.And based on the analysis of simulation results by using Pyrosim software draws the available safe egress time of people(Taset),compared with the required safe egress time of people(Trset)by using Pathfinder software evacuate simulation gets,the main conclusions are as follows:It is educed that the ventilation and smoke exhaust mode of case1?case3 and case5 fails to control the spread of the smoke,only the downwards air velocity of some stairs achieves the requirement of the specification in the simulation time,if in the peak passenger flow period,people is not be able to complete evacuation in the available safe evacuation time.Therefore,the ventilation and smoke exhaust mode needs to optimization and improvement.The improved smoke exhaust mode of case2?case4 and case6 can control the spread of the smoke,and the downwards airvelocity of some stairs achieves the requirement of the specification,people can complete evacuation in 6min.