地铁车站补风对烟流影响的数值模拟

Numerical simulation of the influence of makeup air to smoke flow in metro station

运用FDS对某地铁车站站厅层火灾工况下的排烟和补风效果进行模拟。模拟结果表明,依照规范设计的排烟系统能够满足烟气蔓延范围控制和楼扶梯口下行风速的要求;单侧补风导致烟气滞留现象较为严重,不能保证起火站厅层人员疏散的安全性。针对模拟结果进行优化补风设计,通过优化补风口的位置,使站厅层形成双向补风,提高了站厅层的排烟效率。建议在楼扶梯口位置不能保证地铁车站有效补风的情况下,在补风盲区增设机械或者自然补风系统。

Using FDS to simulate the effect of smoke exhaust and makeup air in metro station.The result showed that the smoke exhaust system designed based on code can satisfy the requirements of controlling smoke spreading and downstream velocity at the stairs.Unilateral makeup air will result in smoke hold-up,and can＇t ensure the safety of evacuation from the station.Against the simulation result,the ventilation efficiency was increased by optimizing the location of the air vent,and form bilateral makeup air.It is suggested that when the location of stair can＇t ensure the makeup air,adding mechanical or natural smoke exhaust system at the blind area is necessary.