双火源隧道火灾的临界风速变化规律研究  

Study on Variation Rules of Critical Ventilation Velocity for Double-source Tunnel Fires

作　　者：刘琼[1] 郑烽 LIU Qiong;ZHENG Feng(School of Resource and Safety Engineering, Central South University, Changsha 410083, China)

机构地区：[1]中南大学资源与安全工程学院

出　　处：《防灾减灾工程学报》2018年第1期137-143,152,共8页Journal of Disaster Prevention and Mitigation Engineering

基　　金：高等学校博士学科点专项科研基金项目(20120162120013)资助

摘　　要：使用FDS数值模拟的方法研究了双火源隧道火灾的临界风速变化规律,重点研究了纵向风下游火源功率及火源间距对临界风速的影响,并从烟气的能量转化过程分析了临界风速的变化原因。结果表明：在上游火源功率及火源间距确定的条件下,临界风速随下游火源功率增加的变化趋势近似呈线性增长;当火源间距为0时,临界风速均等同于与两个火源总功率相同的单火源情形;对于功率确定的上游火源及下游火源,临界风速随火源间距增加的变化趋势近似于二次方递减;对于功率确定的上游火源,每种功率的下游火源都存在一个对临界风速产生影响的＂极限距离＂,且此距离随下游火源功率增加的变化趋势近似呈线性增长。多火源隧道火灾的临界风速相比单火源存在较大区别,因此在隧道的通风设计中,应充分考虑多火源的分布情况,临界风速的计算也更加合理,制定的火灾扑救及人员疏散方案也更加科学。In this paper,the FDS simulation method is used to study the variation of critical ventilation velocity for double-source tunnel fires.The influence of HRR of downstream fire and the distance between the fires on critical ventilation velocity is mainly investigated.By analyzing the process of energy conversion,the reason for this changes is also investigated.The results show that under certain HRR of upstream fire and distance between the fires,the critical ventilation velocity increases approximately linearly with increasing HRR of downstream fire.For the case where the distance between the fires is zero,the critical ventilation velocity is identical to that for single fire with summed HRR.For a certain HRR of upstream and downstream fire,the decrease is quadratic in critical ventilation velocity with increasing distance of fires.For certain HRR of upstream fire,there is always a maximum distance that the critical ventilation distance was no longer influenced by the downstream fire,and the maximum distance increases linearly with increasing HRR of downstream fire.The critical ventilation velocity in double-source tunnel fires is largely different from single fire.Hence for the design of a ventilation system for tunnels,the critical ventilation velocity should be calculated more appropriately by considering the distribution of the fires,and the plan for fire controlling and evacuation work can be conducted more efficiently.

关 键 词：隧道火灾 临界风速 双火源 数值模拟 

分 类 号：X932[环境科学与工程—安全科学]