Air flow and gas dispersion in the forced ventilation of a road tunnel during construction

作     者：Yong Fang Zhigang Yao Shuai Lei 

作者机构：Key Laboratory of Transportation Tunnel EngineeringMinistry of EducationSouthwest Jiaotong UniversityChengduChina School of Civil EngineeringSouthwest Jiaotong UniversityChengduChina 

出 版 物：《Underground Space》 (地下空间（英文）)

年 卷 期：2019年第4卷第2期

页      面：168-179页

核心收录：

学科分类：081406[工学-桥梁与隧道工程] 08[工学] 0814[工学-土木工程] 082301[工学-道路与铁道工程] 0823[工学-交通运输工程] 

基　　金：supported by the National Key Research and Development Program(2016YFC0802205),China the National Natural Science Foundation of China(No:64051578460),China the National Key Research and Development Program of China(2016YFC0802200),China 

主　　题：Tunnel construction Forced ventilation Ventilation arrangement Fluid field Hazardous gases Numerical simulation 

摘      要：Forced ventilation is typically used in the construction of tunnels since it is an economical method to provide high amounts of fresh *** velocity and pollutant concentration near the work face are determined by the ventilation *** the study,field measurement of air velocity was performed,and computational fluid dynamics(CFD)models were constructed to investigate airflow near the work face and predict the gas distribution in a gas tunnel *** effects of the distance between the air duct exit and the work face(L_(1))were evaluated by analyzing the flow field and pollutant *** evaluation shows that the ventilation efficiency improves if L_(1) does not exceed 15 m in a road tunnel with full-face *** respect to a road tunnel with benching excavation,the effects of bench length(L_(2))are analyzed,and the results of the analysis indicate that ventilation efficiency is optimal when L_(2)=5 m and L_(2)=10 m and the air-duct diameter corresponds to 1.6 *** CFD results fit the field measurement significantly well,and the current ventilation system in the construction exhibits a relatively high *** findings of the study aid practitioners in optimizing ventilation efficiency.