宽式防旋墩环形堰竖井水力特性分析  

Analysis of hydraulic characteristics in circular weir vertical shaft with wide anti-rotation pier

作　　者：姜治兵[1] 蒋哲宇 韩松林[1] 杨晓红 JIANG Zhibing;JIANG Zheyu;HAN Songlin;YANG Xiaohong(Hydraulics Department,Changjiang River Scientific Research Institute,Wuhan,430010,China;Changjiang Survey Planning and Design Research Co.,Ltd.,Wuhan,430010,China)

机构地区：[1]长江科学院水力学研究所,湖北武汉430010 [2]长江勘测规划设计研究有限责任公司,湖北武汉430010

出　　处：《人民长江》2024年第9期179-186,共8页Yangtze River

基　　金：中央级公益性科研院所基本科研业务费资助项目(CKSF2023317+SL)。

摘　　要：目前许多拟建抽蓄工程泄洪洞的环形堰竖井入口设置了新型宽式防旋墩,以消除喉口处由不可控漩流引起的呛水等不利流态,而宽式防旋墩环形堰竖井的水气特性与以往采用起旋墩和窄式防旋墩的竖井存在较大差异,业内对其认识尚不清晰。以石台抽水蓄能电站下水库泄洪洞的竖井作为研究对象,采用物理模型试验与数值模拟相结合的手段,分析了流态、流速、压力、消能率等水力指标。研究结果表明:宽式防旋墩引导水流平顺进入竖井形成脱壁流,其尾部可形成顺畅的进气通道,空气经此通道可充分进入竖井以保持井内流态与压力的稳定;新型竖井过流能力满足要求,各部位流速、压力分布正常,总消能率达85%以上;宽式防旋墩可消除不可控漩流导致的呛水现象并引导水流在竖井内形成脱壁流态,使竖井壁面免于空蚀破坏;墩尾通气量足够时,可取消通气管及环形堰与竖井结合部突扩体型,简化工程布置。相关经验可供类似抽蓄电站工程的泄洪洞竖井设计参考。At present,many planned pumping and storage projects have installed new wide anti-rotation piers at the entrance of circular weir vertical shafts of the spillway tunnels to eliminate adverse flow patterns such as choking caused by uncontrollable swirling flow at the throat.The water and air characteristics in the circular weir vertical shafts with wide anti-rotation pier are significantly different from the previous vertical shafts using starting rotation piers and narrow anti-rotation piers.The vertical shaft of the spillway tunnel in the lower reservoir of the Shitai Pumped Storage Power Station was taken as the research object,and hydraulic evaluation indicators such as flow state,flow velocity,pressure,and energy dissipation rate were used to conduct research using a combination of physical model experiments and numerical simulations.The research results showed that the wide anti-rotation pier guided the water flow smoothly into the vertical shaft to form a detached flow,and a smooth ventilation channel could be formed at the tail.Air can fully enter the vertical shaft through this channel to maintain the stability of the flow state and pressure inside the well.The over current capacity of the vertical shaft met the requirements,the flow velocity and pressure distribution in various parts were normal,and the total energy dissipation rate of the vertical shaft was over 85%.The wide anti-rotation pier can eliminate the choking phenomenon caused by uncontrollable swirling flow and guide the water flow to form a detached flow state in the vertical shaft,preventing the wall surface of the vertical shaft from being damaged by cavitation.When the ventilation capacity at the end of the pier was sufficient,the traditional design of the ventilation pipe and the sudden expansion shape at the junction of the circular weir and the vertical shaft can be canceled,simplifying the engineering layout.This experience can be a reference for the similar projects.

关 键 词：宽式防旋墩 环形堰竖井 脱壁流 水力特性 消能率 石台抽水蓄能电站 

分 类 号：TV135.2[水利工程—水力学及河流动力学]