地铁列车着火后在隧道内行驶的安全性对火灾应急救援具有重要意义，而行驶速度是决定着火列车安全性的关键因素．文中以热释放速率为0～10MW的火灾为原型，在1：8的隧道模型内进行列车火灾模型实验．经过相似变换的模型火灾的热释放速率为0—55kW．采用正庚烷为燃料，利用变频风机提供的流场模拟列车在隧道中的运动情况．通过测定不同行驶速度、着火部位及火源位置时，风速与火灾热释放速率的关系、列车周围的温度场以及火灾烟气蔓延规律，并以北京地铁为例，得到着火列车在隧道内行驶的最佳速度为41．83km／h．

The safety of on-fire trains moving in subway tunnel is important to emergency rescue, and the train velocity is the key to the train safety. This paper adopts a fire prototype with a heat release rate of 0 - 10 MW to perform a model experiment of train fire in a 1 ： 8 subway tunnel model. After a similar transformation, the heat release rate of the model fire reaches 0 - 55 kW. By using n-heptane as the fuel and by adopting a frequency conversion fan to form a flow field, the motion of the train in the model tunnel is simulated, and the relationship between the wind velocity and the heat release rate, the temperature field around the train and the flame/smoke pervasion rule are in- vestigated in the conditions of variable train velocity, fire location and fire source location. Finally, by taking Beijing