Study On Fire Smoke Control In A Metro Tunnel With One Opening Portal Based On Field And Network Simulation

As part of the urban transport system,the metro plays an important role in solving problems like city traffic congestion,environmental pollution and so on.While brings convenience to people,it also faced with some serious problems.As the metro tunnel is generally deep underground,the space is often closed,the personnel flow is density,as well as its narrow tunnel,evacuation difficulties.Once there's fire,explosion and other accidents,it will cause great harm to people's life and property safety.When it comes to Chongqing,because of its special geographical features,compared to plain city,its interval tunnel is very different.For example,some metro tunnels with one Opening Portal will be generated.While the research on this type of tunnel is relatively infrequent.Most of the previous simulations on the fires in interval tunnel were based on the network model or field model separately,but due to the current computer level,it's difficult to carry out the whole section of metro line field simulation.In this paper,it has conducted a survey of the tunnel in Chongqing Metro Line 6,including the tunnel structure,the tunnel length and ventilation mode.And establish a field and network model for a metro tunnel with one opening portal tunnel.This paper simulated the fire smoke in the interval tunnel and studied the law of fire smoke in the form of longitudinal ventilation.It is of great theoretical and engineering application to simulate the fire smoke in the metro tunnel with one opening portal based on field and network simulation.The main research work and research conclusion are as follows:(1)It introduced a field and network model by combining the network model and the field model and analyzed the grid size of the field model and the interface position of the field and network model.The availability of the field and network model is verified by comparing its results with the field simulation of the whole tunnel.(2)It explores the effect of shaft air supply / shaft air exhaust on countercurrent smoke control and summarizes the variation law of the temperature under different fire position.(3)It summarizes the variation law of the temperature at the height of the man and the roof of the tunnel in the downstream of the fire source.