地铁站台煤油火灾烟气蔓延的数值模拟

以沈阳地下铁路工程为例.利用计算流体力学的SIMPLE算法,在5种防排烟方式下,对地铁站台煤油火灾烟气的蔓延情况进行数值模拟.选取距地铁站台地面2m平面上,两楼梯口中心点作为测点,得到了不同防排烟情况下测点温度及CO_2摩尔分数的实时曲线,及地铁火场温度和CO_2浓度场云图,分析不同的防排烟方式对地铁站台煤油火灾烟气蔓延情况的影响.模拟结果表明,当仅使用机械排烟时,排烟口位置不同,排烟效果相差不大.加压送风系统与机械排烟同时使用,能有效遏制烟气蔓延,并出现周期性衰减的情况;远离火源的楼梯口可作为更加安全的疏散通道.

Numerical Simulation of Kerosene Fire/Smoke Spread over Subway Station Platform

Based on the Shenyang subway project,a numerical simulation of kerosene fire/smoke spread over the subway station platform was performed by the software CFD and SIMPLE algorithm for fluid mechanics,including 5 different types of smoke exhaust systems.The centers of two stairway openings on the plane 2m above platform floor were taken as test points where the time-dependent relationship between temperature and CO_2 mole fraction and the cloud charts of fire scene temperature and CO_2 concentration fields were obtained to analyze how the different ways to exhaust smoke affect the spread of fire/smoke at subway station platform.The results showed that when the mechanical smoke exhauster is used solely,the position difference of exhauster outlets affects unobviously the fire/smoke control effectiveness.But,the exhauster in combination with forced draft system can inhibit more efficiently the spread of fire/smoke though periodical attenuation is found during the inhibition.The stairway farther from the fire center is proved the safer exit for human evacuation.