空调通风工况地铁站台初期火灾烟气运动规律

Smoke movement of early-stage fire on subway platform under air-conditioning and ventilating condition

通过在地铁站台进行的火灾实体试验,对车站各种空调通风条件下棉绳阴燃火与聚氨酯明火的烟气速度、温度进行监测与分析,研究地铁中具有格栅镂空吊顶的车站站台在不同空调通风工况下火灾初期烟气运动的规律。多点风速探头和温度记录探头设置在火源正上方以及在距火源水平距离约2 m远的4个位置,分别设置在镂空格栅吊顶的上方和下方。在空调通风工况下,送风对烟气的上升有不同程度的抑制作用,一定程度上延长了火源的燃烧时间。对于阴燃火源,烟气温度的降低导致烟气很难升至吊顶上方。

Smoke speed and temperature of cotton rope smoldering fire and polyurethane fire were measured and analyzed under various air-conditioning and ventilating conditions by the way of fire experiments on subway platform.Thus,smoke movement of early-stage fire on the platform with grid ceiling under different air-conditioning and ventilating conditions was studied.The wind speed detectors and temperature detectors were set above the fire and 4 positions horizontally 2 m away form the fire,above and under the fretwork grid ceiling.The air supply delayed the rising of smoke and prolonged the burning time of fire under the air-conditioning and ventilating condition.To smoldering fire,the decline of temperature made the smoke hard to reach the ceiling.