Numerical Simulation Of Smoke Flow Of Subway Fire And Countermeasures Of Safety Evacuation

Being an effect method for relieving city traffic pressure, the subway is developing quicklyin China. However, in the process of subway operation, how to cope with fire precautions andemergency treatment are becoming more and more prominent issues. Due to internal spacerelative close and less evacuation export, Metro tunnels has some characteristics of difficultexclusion of fire smoke, heat concentrated, thermal slow, fast temperature of air, poor visibilityand so on. Once the fire happened, the evacuation of personnel and fighting with fire are verydifficult which involve a big range.The interchange of subway station has a complicatedstructure and many egresses.It is crowded with People and relationship of passenger flow is verycomplicated.Interchange space affects people’s behavior,and limits or inducts happen of thisbehavior.In order to explore the means to escape of subway tunnel and the regularity of fire smokeflow in subway tunnel and development of flue gas diffusion control method, In this paper, thephysical model was established according to the Shenyang subway tunnel structure model andsmoke exhaust in tunnel fire. In this paper, the main consideration is fire development processesfor evacuation effect in the interval tunnel fire, when the fire occurred, due to some reason, trainsmust stop inside the tunnel.In order to reduce the calculation area, shorten the computation time,simulation calculation in tunnel area length is400m, according to the fire in the tunnel of themost unfavorable conditions considered central. Using CFD fluid dynamics simulation softwareSTAR-CCM+on the fire intensity of7.5MW fire intensity numerical simulation, the tunnel toprevent smoke backflow phenomenon of ventilation critical velocity for2m/s.Through the establishment of physical model of a subway station,we mainly discusssubway fire smoke flow regularity and control of flue gas flow diffusion method, and the use ofsoftware of STAR-CCM++on different positions of subway station platform for the flue gasflow and diffusion control numerical simulation. This paper choose transfer Island street station,to a heat and smoke source as one of the cube instead of fire, select stations within mostdangerous position for the flue gas flow numerical simulation. Primary analysis of smoke controlsystem control, flue gas flow and diffusion status, find better escape path, so that the passengersfrom the entrance and exit to escape. These data will provide smoke control system design andaccident plays a guiding role in guiding passenger evacuation.The ventilation inside the subway station and numerical simulation method of fire andunder various working conditions, the obtained temperature, gas distribution rule and theconcentration distribution characteristics under the fire condition, all of these provide referencefor metro construction in China.