地铁站台火灾不同排烟模式下排烟效果的数值模拟研究

运用火灾动力学模拟软件FDS,对广州某一地铁车站岛式站台端部发生5MW火灾的情况进行数值模拟研究,对比分析不同排烟模式下地铁站内的顶棚温度分布、人眼特征高度处温度、能见度、CO浓度分布以及楼梯口风速分布情况,分析其排烟效果是否满足人员安全疏散的要求。结果表明,对于顶棚温度和人眼特征高度处能见度而言,3种排烟模式都能满足要求。对于楼梯口新风风速而言,排烟口为11个的排烟模式不满足要求。比较3种模式下温度和CO浓度的扩散范围,发现排烟口为22个的排烟模式的控烟效果较好,更有利于人员的安全疏散。

Numerical-simulation-based Study on Metro Station Platform Fire Smoke Discharging Effect of Different Ventilation Modes

The occurrence of 5MW fire at the end of the island platform in a Guangzhou metro station is studied with fire dynamics simulation software( FDS). Ceiling temperature distribution,temperature and visibility at the height of human eye, carbon monoxide concentration distribution and wind speed distribution at the stairs are analyzed and compared in different ventilation modes to evaluate the compliance of smoke discharging effect with the requirements for safe evacuation. The results show that all the three modes meet the requirements for ceiling temperature and visibility at the height of human eye; the mode with 11 exhaust ports fails to meet the requirements for new wind speed at the stairs. The comparison of diffusion scope of temperature and CO concentration of the three modes finds that the mode with 22 exhaust ports is more effective for smoke control and evacuation.