考虑下游河道明渠流扰动的尾水隧洞水力波动特性研究  

Study on Hydraulic Fluctuations of Tailrace Tunnel Considering Downstream Channel Open-Channel Flow Disturbance

作　　者：董钟明[1] 郭俊勋 周玉国[1] 田子坚 乔鹏 王兆淼 朱文兵 周大庆[2,3] 于安 王浩博 DONG Zhong-ming;GUO Jun-xun;ZHOU Yu-guo;TIAN Zi-jian;QIAO Peng;WANG Zhao-miao;ZHU Wen-bing;ZHOU Da-qing;YU An;WANG Hao-bo(China Yangtze Power Co.,Ltd.,Yichang 443000,China;College of Water Conservancy and Hydropower Engineering,Hohai University,Nanjing 210098,China;College of Energy and Electrical Engineering,Hohai University,Nanjing 210098,China)

机构地区：[1]中国长江电力股份有限公司,湖北宜昌443000 [2]河海大学水利水电学院,江苏南京210098 [3]河海大学能源与电气学院,江苏南京210098

出　　处：《水电能源科学》2024年第6期59-63,共5页Water Resources and Power

基　　金：国家自然科学基金项目(51979086,51839008);中国长江电力股份有限公司科技项目(5322020001)。

摘　　要：除过渡过程引起的明满流现象外,尾水河道波动同样对长尾水系统的稳定性具有重要影响。基于VOF明渠流模型,研究了下游河道尾水波动对尾水隧洞水力震荡和机组性能的影响。结果表明,调压井后端的尾水隧洞中的压力脉动主要由调压井和下游波浪共同作用引起,呈现出一定的周期性波动;调压井对来自下游的低频脉动具有消波作用,可消除95%以上由波浪引起的低频压力脉动;在下游水位突变的情况下,压力脉动经历了由喷气主导的大波动向下游造波主导的平稳波动的过渡;由下游波浪引起的脉动无法有效传递至转轮区域,受调压室的影响较大;然而喷气引起的某些脉动频率如0.8203 Hz能够有效传递到转轮出口,并保留67.2%的脉动幅值,进而影响转轮性能。In addition to free-surface-pressurized flow phenomenon caused by the transition process,the tailwater channel fluctuation has an important impact on the stability of the long water transmission system.This study investigates the influence of downstream tailwater fluctuations on flow regime transition and unit performance using VOF modeling in open channels.The results reveal that the pressure pulsations in the tailwater tunnel behind the regulating well are mainly caused by the combined effect of the regulating well and downstream waves,exhibiting periodic oscillations.The pressure regulating well acts as a wave attenuator and effectively eliminates more than 95%of low-frequency pressure pulsations caused by waves originating from downstream.Under the sudden changes in downstream water level,the pressure pulsations transition from jet-induced large fluctuations to downstream wave-dominated smooth oscillations.Pulsations caused by downstream waves have limited transmission to the runner area and are significantly influenced by the regulating chamber.However,certain pulsation frequencies induced by jets,such as 0.8203 Hz,can effectively impact the runner outlet and retain 67.2%of the pulsation amplitude,thereby influencing the performance of the runner.

关 键 词：VOF 尾水隧洞 明渠流 造波 可压缩性 

分 类 号：TV135[水利工程—水力学及河流动力学]