纵向通风下隧道速度场及温度场的模拟研究

在隧道火灾研究中,将临界速度作为衡量纵向通风效率的标准已被广泛认可.然而,对于排烟口位于火源两侧,两端都是进风口的情况,临界速度并不能有效地衡量通风效率.对此,研究人员提出了“限制性速度”的概念,并将其作为标准,但到目前为止,对于限制性速度的研究依然很少.本文中的CFD模型以0.Vauquelin的实验为基础,通过CF...     

终南山特长公路隧道火灾通风数值模拟分析

采用计算流体力学方法,对秦岭终南山特长公路隧道进行了火灾通风数值模拟研究。通过对不同纵向通风方案下的气流流动和火灾下游温度分布分析,评估了各通风方案所能达到的效果。比较数值模拟结果和相关的模型试验,发现模拟计算结果取得了满意的预期效果。     

Fire Spread Between Vehicles in Tunnels: Effects of Tunnel Size,Longitudinal Ventilation and Vehicle Spacing

In a number of catastrophic tunnel fire incidents, the fire has often spread from vehicle to vehicle over large distances, occasionally hundreds of metres. Five possible means of fire spread are briefly discussed. The paper focuses on fire spread by flame impingement and investigates the conditions under which flame impingement will occur on a 4 m high HGV downstream of the initial fire. The study uses Bayesian methods to predict the probability of impingement at distances from 0 to 20 m downstream, based on experimental tunnel fire data. The influence of tunnel size, ventilation velocity and vehicle separation on the probability of impingement are discussed. In general it is shown that impingement on a downstream HGV is more likely in a smaller tunnel with a higher ventilation velocity. It is suggested that flames from a HGV fire in a tunnel will almost certainly impinge on a downstream HGV at distances of up to 20 m, and possibly much greater distances.