正压通风在建筑火灾扑救中的应用

Application of positive ventilation in building fire

基于五层单元式住宅楼建立物理模型,利用火灾动力学模拟软件FDS模拟研究火灾发生后采取不同通风措施条件下烟气蔓延流动特点,通过考察火场能见度、温度和CO气体体积分数等参数对比不同措施的排烟效果差异,研究正压通风应用于多层住宅建筑火场排烟的可行性,分析其影响因素。结果发现,建筑结构形式决定了合适的风机布置方式,风机风速大小对于排烟效果影响显著。对于所研究多层单元式住宅楼楼梯间建筑空间形式,利用两台风机分别对起火住户和楼梯间进行正压通风的效果优于仅利用一台风机对楼梯间进行正压通风的效果。

The model of 5-storey unit residential building was established.Fire smoke movement under different ventilation measures was simulated by FDS.Considering the visibility,temperature and CO density development after the fire started,the smoke ventilation efficiency of different measures was compared,and the applicability and influence factors of using positive pressure ventilation in fire rescue was investigated.The results indicated that the arrangement of fans is determined by the building structure and the smoke discharge efficiency is strongly affected by the applied flow velocity.For the 5-storey unit residential building,blow air into the room and the stairwell respectively by two fans is better than blow air into the stairwell by one fan.