Study on the roof fire characteristics of running train in a tunnel
In order to study the fire development characteristics of high-speed running train roof fires in subway tunnel,a series of moving fire experiments were conducted on a constructed down-scaled tunnel train model,setting up different train running speeds and heat release rates,and full-scale numerical simula-tions were combined to reveal the evolution law of the fire charac-teristics of high-speed train roof fires in a tunnel(20~150 km/h).The experimental results show that the maximum temperature on the train roof shows a trend of increasing and then decreasing with the increase of train running speed,in which the maximum tem-perature change reaches 205 ℃;Moreover,with the increase of train running speed,the vertical flame height gradually decreases,and the horizontal flame length shows a trend of increasing and then decreasing,and the critical running speed increases with in-creasing heat release rate,which is verified by numerical simula-tion.Combined with the scaled-down experimental study,a seg-mented prediction model of the flame length of the roof fire of the running train in the tunnel was proposed.
tunnel train firemoving fireflame shapetempera-ture distribution