下卧低压长距离输水隧洞水力特性数值模拟及方案比选  

Scheme comparison and numerical simulation of hydraulic characteristics of underlying low-pressure long-distance water conveyance tunnel

作　　者：张文皎 胡能明 武彩萍[1] 赵荥 ZHANG Wenjiao;HU Nengming;WU Caiping;ZHAO Xing(Key Laboratory of Lower Yellow River Channel and Estuary Regulation,Ministry of Water Resources,Yellow River Institute of Hydraulic Research,Yellow River Conservancy Commission of the Ministry of Water Resources,Zhengzhou 450003,China;Yellow River Engineering Consulting Co.,Ltd.,Zhengzhou 450003,China)

机构地区：[1]黄河水利委员会黄河水利科学研究院,水利部黄河下游河道与河口治理重点实验室,河南郑州450003 [2]黄河勘测规划设计研究院有限公司,河南郑州450003

出　　处：《水资源与水工程学报》2023年第3期123-128,135,共7页Journal of Water Resources and Water Engineering

基　　金：河南省重大公益专项项目(201300311600);中央级公益性科研院所基本科研业务费专项项目(HKY-JBYW-2020-18、HKY-JBYW-2021-09)。

摘　　要：长距离输水隧洞线路布置过程中时常遇到缺陷性地层等影响工程安全的不利因素,下卧低压布置法是解决这类问题的一种较优的处置手段。依托某下卧低压长距离输水工程,选取箱涵、分水口、下卧低压洞进出口竖井、下卧低压洞段和部分明流洞段作为研究段,建立三维数值模型,采用RNG k-ε双方程紊流模型结合VOF法开展数值模拟计算,研究下卧低压长距离输水隧洞沿程水力特性分布及变化规律,进行不同隧洞方案比选。研究表明:不同工况下下卧低压隧洞各部位水流衔接均相对平顺,没有出现明满流交替现象,下卧低压洞进出口竖井内的流速分布较为复杂;随着进口竖井直径的增大,隧洞内水气及水面线分布情况变化不大,进口竖井内流速梯度有所降低,出口竖井流速分布变化不大,研究成果可为下卧低压长距离输水隧洞的方案设计提供参考。In the process of long-distance water conveyance tunnel construction,the unfavorable factors affecting the project safety often occur,such as defective strata.The underlying low-pressure layout method is an excellent approach addressing such problems.Taking a long-distance underlying low-pressure water conveyance project as the research object,a few sections,such as the box culvert,water diversion outlet,inlet and outlet shaft of the underlying low-pressure tunnel,underlying low-pressure tunnel section and some open flow tunnel sections were selected for the establishment of a three-dimensional numerical model.The RNG k-εtwo-equation turbulence model combined with the VOF method was used to carry out the numerical simulation,and the distribution and change law of hydraulic characteristics along the underlying low-pressure long-distance water conveyance tunnel were studied for the comparison and selection of different tunnel schemes.According to the research,under different working conditions,the flow connection of each part of the underlying low-pressure tunnel was relatively smooth,and the phenomenon of alternating open and full flow did not occur.The velocity distribution in the inlet and outlet shaft of the underlying low-pressure tunnel was rather complicated.With the increase of the diameter of the inlet shaft,the distribution of water,gas and water surface line in the tunnel did not change much,the velocity gradient in the inlet shaft decreased,and the velocity distribution in the outlet shaft changed little.The research results can provide some reference for the design scheme of underlying low-pressure long-distance water conveyance tunnels.

关 键 词：输水隧洞 下卧低压布置 进口竖井 水力特性 数值模拟 

分 类 号：TV68[水利工程—水利水电工程]