Research On The Fire Characteristic Of Moving Subway Train

With the acceleration of social, economic and urban construction, subway has become one of the most important vehicles in Beijing and is developing at high speed. In case of the on-fire train moving forward in subway tunnel, the subway train design specification has not clearly provided the safety speed of the train in the tunnel and the operational mode of ventilation and smoke extraction system. So, it is very necessary to study the fire characteristic of moving subway train, which is helpful for promoting the researches on the safety speed of on-fire train moving in the subway tunnel. The research is of great realistic significance and scientific significance.Now, the main research methods of the subway system fire are full-scale test, model experiment and numerical simulation. The full-scale tests and model experiments are required a lot of manpower and resources, and the working conditions is very limited. Therefore, computer simulation has become an important research method for subway fire. Currently, computational fluid dynamics simulation technology has been widely used for the design of subway fire smoke exhaust system and its disaster relief system, and has achieved good results.The paper takes the tunnel between the Jishuitan and Guloudajie station of Beijing subway as the research object, and study the fire characteristic of moving subway train mainly through the method of numerical simulation. Firstly, The paper uses STAR-CD software to simulate the model experiments. By comparing the results of experiment, the accuracy and applicability of the fire model has been verified.On the basis of this, a variety of conditions of moving fire of scale and prototype subway train have been simulated by using the function of moving mesh in STAR-CD, then the relationship between the train speed and the characteristics of smoke movement and temperature distribution is established. The results show that:with the increase of train speed, the maximum temperature will decrease gradually, at the same time the range of smoke will extend; When the train speed is 40km/h, the temperature at the top and the downstream of fire source is at a low level with the minimum spread speed of smoke. Finally, by analyzing the results of model experiments and numerical simulations, the paper proposes the reasonable speed of the on-fire train in the subway tunnel should be 40km/h.