摘要
火灾临界风速是地铁隧道排烟系统设计的重要设计依据,而列车阻塞效应会影响地铁隧道火灾临界风速。该文开展了地铁列车阻塞效应对地铁隧道火灾临界风速影响的FDS数值模拟研究,利用热烟验证试验和单元格敏感分析确保FDS数值模拟结果的准确性。研究结果显示,列车阻塞长度对地铁隧道临界风速几乎没有影响,列车阻塞会使地铁隧道火灾临界风速变大,列车拥塞区域的火灾临界风速会因局部风速增大而变小,且地铁隧道阻塞比的增大率与临界风速的减小率之间呈线性关系。根据理论分析结果和模拟数据,建立了考虑列车阻塞效应的地铁隧道火灾临界风速预测公式。
Critical velocity is very important to smoke control in longitudinally ventilated subway tunnel fires. When the metro train is in the subway tunnel, the ventilation flow is accelerated in the block region due to conservation of mass.Hot smoke validation experiment and grid sensitivity analysis were conducted to ensure the accuracy of numerical simulation results. Numerical simulations were carried out to respectively study the effects of train blockage ratio and train blockage length on critical velocity in subway tunnel fires. Results show that train blockage length has no significant influence on critical velocity in subway tunnel fires. Critical velocity in subway tunnel fires with train blockage is higher than that of subway tunnel fires without train blockage. With the increase of train blockage ratios, the critical velocities of subway tunnel fires decrease. There is a linear relationship between the increase rate of train blockage ratios and the decrease rate of critical velocities in subway tunnel fires. Finally, according to the results of theoretical analysis and numerical simulations, a modified critical ventilation velocity prediction model including the factors of blockage ratio is proposed for subway tunnels with train blockage.
作者
夏三县
张晓伟
胡璠
王海涛
XIA San-xian;ZHANG Xiao-wei;HU Fan;WANG Hai-tao(Zhengzhou Metro Group Co.,Ltd.;Beijing Urban Construction Design&Development Group Co.,Ltd.;College of Civil Engineering,Henan University of Technology)
出处
《建筑热能通风空调》
2022年第9期89-92,共4页
Building Energy & Environment
基金
河南省科技攻关项目(192102310229)。
关键词
地铁隧道
列车阻塞
临界风速
火灾
subway tunnel
metro train blockage
critical velocity
fire
