摘要
为明确气压等环境参数对粉尘运移的影响,掌握高海拔隧道空间重点产尘工序粉尘质量浓度分布,使用Fluent软件模拟隧道喷浆和出碴阶段风速场和粉尘质量浓度场,分析海拔对隧道空间内风流和粉尘质量浓度波动性的影响。通过曲线拟合风速场和粉尘质量浓度场的沿程分布,建立隧道粉尘质量浓度预测模型。引入风速不均匀度和粉尘质量浓度不均匀度参数,构建海拔与风速、粉尘质量浓度不均匀度的线性回归方程。研究结果表明:1)高海拔地区隧道通风过程中,粉尘运移速度接近风速所用时间相比平原地区较长;低海拔地区风流接近直线沿全断面流出隧道,随着海拔升高,风流覆盖范围逐渐缩小,风流在水平方向逐渐沿S型流出隧道。2)喷浆过程中,距掌子面40 m以内风速较高,40 m以外风速迅速下降,在距掌子面60~180 m均匀波动;隧道整体粉尘质量浓度随海拔上升而发生波动性变化,在距掌子面20~180 m均匀下降,呈近似线性降低。3)出碴过程中,海拔上升,断面平均风速和呼吸面平均粉尘质量浓度值无明显变化,风速不均匀度和粉尘质量浓度不均匀度逐渐呈线性升高;海拔每上升1 000 m,风速不均匀度上升0.156 m^(2)/s^(2),粉尘质量浓度不均匀度上升4.42×10^(-6)kg/m^(3)。
Fluent software is employed to simulate the wind velocity and dust concentration fields during shotcreting and mucking in a tunnel to clarify the influence of environmental parameters,such as air pressure,on dust transportation and explore the dust concentration distribution during crucial dust-producing processes in high-altitude tunnel spaces.The impact of altitude on the airflow and dust concentration fluctuations in the tunnel is then analyzed.A dust concentration prediction model is established by fitting the wind velocity and dust concentration distribution along the tunnel.A linear regression equation is constructed to relate altitude to wind velocity and dust concentration distribution-nonuniformity parameters.The research results demonstrate the following:(1)In areas of high altitude,the dust transport speed during ventilation reaching wind speed is longer than that of plain areas.In low-altitude areas,the airflow is nearly linear and flows out of the tunnel along the entire cross-section.As the altitude increases,the coverage range of the airflow gradually decreases,and the airflow along the tunnel moves in an S shape.(2)During shotcreting,the wind speed is higher within 40 m from the tunnel face;it lowers rapidly when the distance from the tunnel face is more than 40 m,and it uniformly fluctuates when the distance from the tunnel face is between 60 and 180 m.The overall dust concentration within the tunnel fluctuates with increasing altitude,decreasing uniformly between 20 and 180 m from the tunnel face and approximately linearly.(3)During mucking,the average wind speed and dust concentration of the entire cross-section remain unchanged with increasing altitude,whereas the nonuniformity of the wind speed and dust concentration increases linearly.For every 1000 m increase in altitude,the nonuniformity of wind speed and dust concentration increases by 0.156 m^(2)/s^(2) and 4.42×10^(-6)kg/m^(3),respectively.
作者
马国栋
黄嘉洵
王栋
尹龙
周川川
张江石
MA Guodong;HUANG Jiaxun;WANG Dong;YIN Long;ZHOU Chuanchuan;ZHANG Jiangshi(China Railway Tunnel Group(Shanghai)Special High-Tech Co.,Ltd.,Shanghai 201306,China;School of Emergency Management and Safety Engineering,China University of Mining and Technology(Beijing),Beijing 100083,China;China Railway Tunnel Group Co.,Ltd.,Guangzhou 511458,Guangdong,China)
出处
《隧道建设（中英文）》
CSCD
北大核心
2024年第6期1241-1250,共10页
Tunnel Construction
基金
中国中铁股份有限公司科技研究开发计划(CZ02-专项-02)。
关键词
高海拔隧道
压入式通风
喷浆
出碴
风速场
粉尘运移
数值模拟
high-altitude tunnel
press-in ventilation
shotcreting
mucking
wind velocity field
dust transport
numerical simulation
