隧道侧壁排烟烟气特征的数值模拟  

Numerical Simulation Study on the Performance of Tunnel Lateral Exhaust Smoke

作　　者：李钰[1] 蔡世杰[1] 朱凯强[1] 

机构地区：[1]大连交通大学土木与安全工程学院,辽宁大连116028

出　　处：《大连交通大学学报》2016年第3期68-72,共5页Journal of Dalian Jiaotong University

基　　金：辽宁省教育厅高等学校科学研究计划资助项目(L2015096)

摘　　要：为了更好地研究隧道侧壁排烟系统的性能,利用FDS软件建立长450 m的大排烟口隧道模型,并以此为模拟对象.对不同排烟速率下的隧道内烟气层温度、厚度进行了数值模拟分析.结果表明:排烟速率0~60m^3/s时,烟气层厚度随排烟速率的增大而减少;80~180 m^3/s时,烟气层厚度反而增大.排烟速率一定时,烟气层厚度沿排烟口横向和纵向会出现先降低后增大的变化;但总体上来看,变化很平缓.排烟速率较小时,火源左侧和右侧烟气层厚度和温度的平均值都比较接近;随着排烟速率的增大,厚度和温度的平均值出现差值,并且差值明显大于排烟速率较小时.因此,为了使排烟系统性能达到最大化,需选取合适的排烟速率.For better understanding of the performance of tunnel lateral exhaust smoke,FDS software is used to establish the large exhaust vent tunnel model with the length of 450 m. Under different exhaust rates,the tunnel smoke layer temperature and thickness are analyzed. It shows that when the exhaust rate is 0- 60 m^3/ s,the sunken smoke layer thickness is decreased with the increasing of exhaust rate. When the exhaust rate is 80-180 m^3/ s,the smoke layer thickness is increased. When the exhaust rate is constant,smoke layer thickness is decreasd first and then increased along the vent lateral and longitudinal direction very gentle variation. When the exhaust rate is small,smoke layer thickness and temperature change little with a close mean value. With the increasing of exhaust rate,difference value appears in the fire source left and right smoke layer thickness and temperature. Besides,the mean difference value is obviously larger than that of lower exhaust rate.Hence,suitable exhaust rate should be chosen in order to make the exhaust system to maximize performance.

关 键 词：火灾 侧壁排烟 排烟速率 烟气参数 

分 类 号：U453.5[建筑科学—桥梁与隧道工程]