隧道坡度变化对全射流纵向通风效率的影响研究  

Impact of the tunnel slope degree changes on the efficiency of the full jet fan longitudinal ventilation

作　　者：孔杰[1] 徐志胜[1] 黄俊 梁印 李志远 游温娇 KONG Jie;XU Zhi-Sheng;HUANG Jun;LIANG Yin;LI Zhi-yuan;YOU Wen-jiao(Institute of Disaster Prevention Science and Safety Technology,Central South Universily,Changsha 410075,China;Jiangsu Transporlation Institute Group,Nanjing 211112,China;College of Quality&Safety Engineering,China Jiliang University,Hangzhou 310018,China)

机构地区：[1]中南大学防灾科学与安全技术研究所,长沙410075 [2]苏交科集团股份有限公司,南京211112 [3]中国计量大学质量与安全工程学院,杭州310018

出　　处：《安全与环境学报》2020年第6期2211-2217,共7页Journal of Safety and Environment

基　　金：江苏省住建厅科研项目(2016ZD78);江苏省住建厅科研项目(2017ZD134);浙江省安全工程与技术研究重点实验室项目(201902)。

摘　　要：城市公路隧道中"V"字或"W"字的坡度变化会导致隧道通风系统作用效果降低,通风能耗增加。为解决隧道坡度变化时纵向通风效率下降问题,利用ANSYS Fluent软件,建立了以单一坡度变化范围在0~3%,双坡度变化范围分别为(-4%,+4%)、(+4%,-4%)的全射流纵向通风模型。模拟结果表明,单一隧道坡度从0增大到3%,风机升压系数从0.794下降到0.683,降幅达14%。随坡度增大和坡度数量增多,隧道断面平均速度越低,气流低速边界层越厚,射流风机升压系数越小,通风系统的效率越低。与无坡度变化的水平隧道相比,双坡度变化隧道内风机升压系数降低可达25%。建议隧道内风机布置应远离坡度变化区域,并重点采用减小风机出口风速和增大风机直径的方法来提高隧道通风效果。To improve the longitudinal ventilation efficiency in the slope tunnels,given paper has taken the software known as the ANSYS Fluent to establish a series of slope tunnel models with the full-jet longitudinal ventilation.Influenced by the geological terrain conditions,the construction technology and some other factors,the slopes in the letters"V"or"W"shapes can often come up in the urban highway tunnels,which are often likely to reduce the ventilation efficiency and increase the ventilation energy consumption in the tunnel,and,even worse,affect the air ventilation quality inside the tunnel.And,for the research purpose,we have established 7 simulation conditions,which can be divided into 2 groups according to the slope changes.For instance,in accordance with the single slope conditions,the slope can vary from 0%to 3%,whereas,in the double slope conditions,the slope degree changes can be traced in the following 4 kinds,i.e.,(-4%,+4%),(+4%,-4%),which should be the limited values of a corresponding slope in the project.And,later,we have made an investigation of the particular features and mechanism of the air flow in the tunnel,with the analysis of the pressure coefficient of the jet fan under the different slopes.And,consequently,the speed cloud diagram of the fan outlet from 80 m to 200 m shows that the wind speed in front of the fan proves uniform,whilst there has been found a high-speed jet at the fan outlet,a lower speed air stagnation zone below and near both of the jet sides.At the same time,with the increase of the distance between the cross section and the fan itself,the effective ventilation area tends to increase with the gradual extension of the area of high-speed airflow and moves to the middle of the tunnel.With the increase of the slope degree and the number of slopes,the average velocity on the cross-section tends to get smaller,whilst the boundary layer of the low-speed airflow gets thicker,which leads the pressure-rise coefficient of the jet fans to decrease and the drop of the ventilation efficienc

关 键 词：安全工程 公路隧道 纵向通风 坡度隧道 射流风机 通风效率 

分 类 号：X962[环境科学与工程—安全科学]