双火源对隧道火灾临界风速影响的数值研究  

Numerical studies on the effect of double fire sources upon critical ventilation velocity in tunnel fires

作　　者：余明高[1,2] 苏冠锋 陈静[1] 

机构地区：[1]河南理工大学安全科学与工程学院,焦作454003 [2]重庆大学煤矿灾害动力学与控制国家重点试验室,重庆400044

出　　处：《火灾科学》2017年第1期20-28,共9页Fire Safety Science

基　　金：国家自然科学基金项目(U1361205;51574111);煤矿灾害动力学与控制国家重点实验室自主研究课题重点项目(2011DA105287-ZD201401)

摘　　要：为研究双火源隧道火灾所需临界风速的变化规律,利用火灾动力学软件FDS模拟了三种双火源隧道火灾,即两等火源功率的火灾、上风流火源功率较大火灾、上风流火源功率较小火灾。根据各火灾情景下所得临界风速u_(cr),分析两火源距离d、火源功率、上下风流位置关系对临界风速u_(cr)的影响规律。结果表明:随着两火源距离d的增加,所需临界风速u_(cr)逐渐减小,当两者达到临界距离d_x时,临界风速u_(cr)为稳定值,该值由两火源上下风流位置关系和总火源功率共同决定;同种双火源火灾随着总火源功率增大,所需的临界风速u_(cr)增大;随着两火源间距离d增大,各双火源火灾所需临界风速u_(cr)的减小幅度不同;两火源距离d为零时,所需临界风速u_(cr)略大于同火源功率的单火源火灾所需的临界风速。Numerical analysis was adopted to explore the critical ventilation velocity ucr for double-source tunnel fires. Three kinds of double-source tunnel fires, namely two identical heat release rate（HRR） fire, a larger upstream fire and a smaller upstream fire, were simulated by FDS software. And the impact of the distance d between the two fire sources, position of them and the summed HRR upon Ucr was analyzed according to the simulation results. The results show that ucr declines with d increase. When the distance reaches the critical value dx, uor becomes constant and it is determined by the position and summed HRR of the two fire sources. If the summed HRR of a double-source fire increases, the increase in ucr becomes significant. The Ucr decreases with the added distance d, which is needed by different kinds of double-source fires. But the diminished ucf value is different. The ucr for double-source fire is higher than that for the single fire with summed HRR when d is 0.

关 键 词：隧道火灾 数值模拟 双火源 临界距离 临界风速 

分 类 号：X913.4[环境科学与工程—安全科学] U453.5[建筑科学—桥梁与隧道工程]