Scale modeling on the effect of air velocity on heat release rate in tunnel fire

There are concerns that the air supply rate would increase in a tunnel with a moving train. Higher relative air velocity between the train wall and air caused by piston effect would then give higher burning rates in a tunnel fire. In this article, the effect of air velocity on heat release rate in a subway fire was studied in a scale model tunnel. Heptane was used as the fuel. Results showed that increasing the air velocity to fire would increase the heat release rate. This point should be considered in designing fire safety management schemes in subways when the train is moving in tunnels.