半横向通风方式隧道内污染物分布的数值仿真  

Numerical Simulation and Engineering Applications of Pollutant Distribution inside the Tunnel with Semi-transverse Ventilation System

作　　者：任锐[1] 谢永利[1] 楼慧元[1] 

机构地区：[1]长安大学公路学院,西安710064

出　　处：《防灾减灾工程学报》2011年第1期96-101,共6页Journal of Disaster Prevention and Mitigation Engineering

基　　金：交通部西部交通建设科技项目(20073180038)资助

摘　　要：某城市公路隧道采用半横向通风方式进行火灾排烟,其排风孔位于隧道侧壁顶部。针对该城市公路隧道,运用CFD数值仿真方法建立1:1的三维数值仿真模型,模拟不同工况下,开启不同形状排风孔时,隧道内的风速、风压以及污染物浓度的分布情况。研究表明,排风孔所在位置的隧道横断面上,形成一个左侧区域负压较高、压强变化梯度大而右侧区域负压较小的"排风横断面";随着排风孔开口高度的增加,排风横断面上负压分布向右侧扩大,右侧区域风速增加,有利于右侧区域内污染物的稀释,而左侧区域竖直方向风速减小,左下角区域风流方向紊乱,左侧区域污染物不能得到有效稀释,浓度较高。Considering the semi-transverse exhaust ventilation of a certain city tunnel,the ventilation hole was made in the upper left wall in the tunnel.We established an 1：1 three-dimensional simulation model by using the computational fluid dynamics numerical simulation method and simulated wind speed,air pressure and the concentration of pollutants in the tunnel in different conditions and made different shapes of ventilation holes,and then carried out the comparative analysis,and drew some conclusions：in the tunnel cross section with ventilation hole,a ＂exhaust section＂ is formed,for which high negative pressure and large pressure gradient are in left region and small negative pressure is in right region;With the increasing height of ventilation hole,the distribution of negative pressure expends to the right of the exhaust section and the wind speed increaes in the right region and is helpful to the dilution of pollutants in the right region, but the vertical wind speed reduces and the direction of flow is disordered in lower left region that makes the concentration of pollutants greater in left region.

关 键 词：隧道通风 半横向 污染物浓度分布 排风孔开口高度 数值仿真 

分 类 号：U45[建筑科学—桥梁与隧道工程]