地铁列车行驶速度对火灾烟气温度特性的影响

Influence of subway train speed on fire smoke temperature characteristics

采用缩尺实验台研究运行地铁车厢顶部着火后的温度分布特征,设定12.34,15.60,18.25,21.47和25.10kW5种火源功率,在0,40,60和80 km/h这4种不同列车运行速度下进行实验,分析顶棚最高温度、温度衰减区域及其下降速率。研究结果表明:当速度≤60 km/h时最高温度点均在火源点上方,风速增加后火焰朝着下风向蔓延,距离火源点0.9 m的位置是温度下降最剧烈的区域。根据不同实验工况测得温度分布情况,判定列车以4种速度运行时,发生火灾后车厢的高危区域。当运行列车发生火灾后,进行人员疏散时可以根据划分的危险区域选择安全的疏散方向和区域,为火灾的应急处置和人员救援提供优化方案。

A scale test bed was used to study the temperature distribution characteristics of the fire on the top of the subway car,and five fire source powers of 12.34,16.60,18.25,21.47 and 25.10 kW were set.Experiments were carried out under four different train speeds conditions of 0,40,60 and 80 km/h.The maximum temperature,temperature decay zone and descent rate of the ceiling were analyzed.The results show that the highest temperature point is above the fire source point when the train speed is≤60 km/h.After the wind speed increases,the flame spreads toward the downwind direction.The position of 0.9 m from the fire source point is the most severe temperature drop.According to the temperature distribution measured in different experimental conditions,The high-risk areas are determined when the train is in motion at four speeds.When a train fire occurs,a safe evacuation direction and area can be selected to evacuate personnel according to the classified dangerous area,and an optimization scheme is provided for emergency treatment and personnel rescue of the fire.