Theoretic Analysis And Experiment Study Of Burning Characteristic And Safety Of Moving Train In Subway Fire

Along with the development of subway in city, researchers pay more and more attention to the subway fire. But the subway fire has the more dangerous. When a train catch on in subway tunnel, many overseas and inland criterion prescribe that it should let the train run to next station as soon as possible. In this case, the safe velocity by which the train goes to next station is an important problem. This thesis colligates a lot of overseas and inland information and combines the methods of numerical simulation and model experiments to analyse the safety of on-fire train's moving, and put forward the practical emergency plan which will have instructional meaning to subway project.When the train catches on fire in subway tunnel, there are two factors which impact the fire development, burning process of comburent and influence of surrounding flow field.Burning characteristic of comburent is the decisive factor to fire size and smoke release capacity. This thesis begin with the comburent in subway fire to study the HRR(Heat Release Rate) and smoke release characteristic, then analyse the cause and characteristic of subway fire and summarize how to determine the subway fire size. At last the smoke release capacity and toxicity is analysed. By the means of oxygen consumption measurements, this thesis use model experiment to study the HRR and smoke toxicity in subway tunnel fire. Through the experiment, we confirm the characteristic of heat and smoke release in subway tunnel and analyse the fire fatalness.Ventilating condition of fire surroundings is an important factor to influence the fire development. The high velocity airflow around running train will give fire much oxygen, which will let the fire expand and spread, so it is necessary to study the velocity field around the moving train in subway tunnel. This thesis on one hand does the model experiment to study the influence of wind to fire. Through compare the HRR in different wind velocity we confirm the wind influence to fire HRR. On the other hand, the flow field around a moving train is simulated by CFD software, then the characteristic of velocity field is analysed.Combined with the results of numerical simulation and experiments study, this thesis analyse the safety problem of moving train fire, and put forward the Safe Velocity when trains catch on fire in subway tunnel, also prove that this operating scheme has more advantage to evacuation and succor. This thesis has practical value to the safe operation of Chinese subway...