公路隧道中临界风速数值模拟研究

Numerical simulation study on critical wind speed of the highway tunnel

利用性能化防火设计的思想,结合工程算例,运用模型实验和数值模拟的方法对公路隧道火灾进行研究。实验验证隧道中存在烟气逆流现象;数值模拟得到不同火源功率下相应的临界风速：火灾功率为5、20、100 MW时,临界风速分别为4.0-4.5、6.0-6.51、0.0-10.5 m/s。研究发现,隧道内的临界风速与燃烧强度有关;当纵向通风速度等于临界风速时,不会发生逆流现象,有利于火源上风区域的人员逃生和消防救援工作的开展。

The idea of performance-based fire-protection design has been used and combined with project example to study highway tunnel fire with model experiment and numerical simulation.Experimental results confirms the smoke counter-current phenomenon in the tunnel;Critical wind speeds for different fire power are given： when fire power are 5 MW,20 MW,100 MW,the critical wind speeds are 4.0～4.5 m/s,6.0～6.5 m/s,10.0～10.5 m/s.It is found through the study that the critical wind speed inside the tunnel is concerned with combustion intensity;the phenomenon does not occur upstream,when the vertical air velocity is equal to the critical wind speed,which is conducive to escape for the upwind areas and carry out the fire rescue.