Syudy On Subway Tunnel Smoke Characteristics Of The Burning Train In Running Condition

With the rapid development of urban subway construction in China, there are more and more high speed metro train appear to alleviate urban traffic congestion problem. However, the increase of running speed and train numbers also brings a bigger fire safety hidden trouble.Under the background of metro running tunnel with evacuation platforms, this paper do the numerical simulation research on the critical wind speed of longitudinal smoke control in middle carriage after fire aecidents and the features of fire smoke spread after fire aecidents when trains moving by using the STAR-CCM+embedded fire module. The research result provide a reference for designing subway smoke control system and developing tunnel fire rescue strategies.Firstly, this paper simply introduced the parameter setting and numerical computation method of STAR-CCM+embedded fire module. After reliability demonstration, we brought in the influencing factor about train jam and evacuating gate opening to establish a more realistic tunnel fire scene. Through numerical simulation methods, we got the critical wind speed of longitudinal ventilation in metro tunnel under different fire scales and design speed. We used the tunnel blockage ratio factor to modify previous research model, and then we verified it by previous simulation results. The result shows that the model fits the data, and we finally determined the critical wind speed model which could be uesed in designing subway smoke control system.Then, for a full-size existing subway tunnel, based on the coupled solution of train movement and combustion, detailing the determination method of the boundary conditions that continued movement of the burning train model, and introduce implementation process that the train continues to run after on fire, Establish a three-dimensional numerical model can be used to analyze the tunnel fire smoke characteristics under train operating conditions.Finally, based on the dynamic tunnel fire model, were carried out the study on the tunnel fire smoke characteristics in two mode, which the train continues to keep constant speed after on fire and decelerate to a stop transport. Calculate the minimum longitudinal ventilation velocity under the influence of the piston wind, and make make a suggestion on fan opening mode and evacuation method in subway tunnel fire.