保障隧道列车着火后继续向前行驶的安全性是火灾应急救援的目标． 文中采用计算流体动力学方法，使用 STAＲ-CCM + 软件的滑移网格功能，研究了不同列车行驶速度和火源热释放速率对隧道内烟气特性的影响，得到列车携带火源在隧道内行驶时烟气温度的分布规律和最佳行驶速度． 结果表明:隧道列车着火后继续向前行驶时，存在一个使温度达到最低的最佳行驶速度50km/h;当列车运行速度恒定时，火灾热释放速率越大，人眼高度处的最高温度也越高;热释放速率恒定时，最高温度随着列车行驶速度的增大先减小后增大，呈开口向上的抛物线形状;随着着火列车向前运行，列车车顶进风口的最高温度逐渐上升，在隧道横断面的中性面上，最高温度值有较大的振荡;在隧道内 340 m 处温度最低，但是也达到了 166． 45℃． 列车顶部区域的温度过高，可能会被烧毁性破坏，因此可考虑在列车着火后继续向前运动的同时给隧道通风，以降低环形空间的温度．

Ensuring the safety of the on-fire train moving in a subway tunnel is the goal of the corresponding emer- gency rescue.In this paper,with the help of STAR-CCM + possessing the function of mesh sliding,CFD (Com- putational Fluid Dynamics) simulations are carried out to investigate the effects of train speed and heat release rate on the smoke characteristics in a tunnel,and the distribution of smoke temperature as well as the optimal speed of the on-fire train traveling in the tunnel are explored.The results show that (1) for the on-fire train moving in a subway tunnel，there is an optimal speed corresponding to the lowest temperature,namely 50 km/h; (2) when the train moves at a constant speed,the temperature peak at the typical eye points increases with the heat release rate; (3) at a constant heat release rate,the maximum temperature first decreases and then increases with the train speed,presenting an upward parabola; (4) the temperature at the train roof inlet gradually increases when the on-fire train moves forward in the tunnel,and the maximum temperature is of a large oscillation on the neutral surface; (5) the minimum temperature (166. 45 ℃) occurs at 340 m in the tunnel; and (6) the train might be burnt due to the high temperature at the train top,so that a ventilation measure should be adopted to reduce the temperature of the annular tunnel space when a subway train is on fire.