纵向通风下地铁疏散走道内烟气运动特性

以福州地铁四号线的一个地铁隧道区间为研究对象，利用FLUENT构建车头电气火灾的数值模型。重点分析了在阻塞比为0.38与0.55条件下火灾烟气的运动特征及对疏散人员的影响。模拟结果表明:在火源上游位置，在未开启通风和开启通风的条件下，高温烟气聚集在隧道顶部，随高度下降，烟气温度降低，建议设置离轨面高度较低的疏散走道以提供更大的安全空间。同时，在未开启通风，且火源释热率及火灾发展时间相同的情况下，高阻塞比隧道内的初始温度较高；开启纵向通风后，对流换热增强，降温快，高温烟气在火源上游沿隧道长度方向、高度方向的运动都能得到有效的控制，有利于人员疏散。最后，给出了纵向通风条件下的疏散方案及建议。

Characteristics of smoke movement in subway evacuation pathways under longitudinal ventilation

Taking a subway tunnel section of Fuzhou Metro Line 4 as the research object, a numerical model of the locomotive electrical fire was constructed with FLUENT. Emphasis was put on the analysis of fire-induced smoke movement impact on evacuees when the blockage ratio was 0.38 and 0.55, respectively. Simulation results show that in the upstream position of the fire source, whether vented or not, smoke with a higher temperature appears primarily near the tunnel ceiling, and the smoke temperature decreases with the height falling. When the ventilation is not turned on, the initial temperature of the tunnel with the higher blockage ratio appears to be higher after the same fire development time and heat release rate. After introducing longitudinal ventilation, the convection heat exchange is enhanced and the cooling is faster.In the upstream of the fire source, the movement of high temperature smoke along the tunnel length direction and height direction upstream of the fire source can be effectively controlled. This is beneficial for the evacuation process. At last, the evacuation plan and suggestions underthe longitudinal ventilation are given.