摘要
针对引水式水电站进水口推移质泥沙淤积严重的问题,本文提出一种L型导沙坎结构。以锦屏二级水电站为例,通过数值模拟和动床物理模型试验,对比传统直线导沙坎,研究了L型导沙坎的水力特性与防沙效能,分析了其布置数量、高度、角度及水力参数的影响。结果表明:L型导沙坎具有良好的防沙性能,在引导泥沙远离进水口的同时能够有效减少泥沙向坎后运动。导沙坎高度对防沙效果影响显著,高度增加2 m,拦沙坎后泥沙淤积体积可减少59%。在不同分流比和弗劳德数下,L型导沙坎均能有效防沙,但随着二者增大,泥沙靠近上游首个导沙坎,导沙坎背水侧及拦沙坎后方的泥沙淤积有所增加。此外,L型导沙坎对水头损失影响较小,相对高度5 m时,与无导沙坎相比,平均水头损失仅增加0.069 m。研究成果为类似进水口防沙设计提供了新方案与解决思路。
To address severe bed load sedimentation at the intake of a diversion-type hydropower station,this study works out a new L-shaped structure of sediment diversion sills.A laboratory scale model experiment and numerical simulations are used to study the behaviors of these sills on a movable-bed in a case study of a large diversion-type hydropower station.Their hydraulic characteristics and sediment exclusion effectiveness are examined using comparative analysis against the traditional sills of straight shapes,focusing on the effects of their layout parameters(spacing,height,and angle)and hydraulic parameters.Results demonstrate the L-shaped sills achieve superior sediment exclusion performance,effectively diverting sediment away from the intake while minimizing sediment migration behind them.The sill height imposes a critical influence on exclusion efficiency-a 2 m increase leads to a 59%reduction in sediment deposition volume behind the sediment retention sill.The diverting sills maintain effective sediment control under varying diversion ratios and Froude numbers,but as both parameters increase,sediment migrates toward the first upstream sill and deposition increases on its lee side and behind the retention sill.And,the structure causes minimal extra head loss-its average head loss is as low as 0.069 m at the relative sill height of 5 m.Thus,the L-shaped sill and its design provide a novel solution to sediment control in water intake structures.
作者
练继建
李金轩
刘昉
徐奎
LIAN Jijian;LI Jinxuan;LIU Fang;XU Kui(State Key Laboratory of Hydraulic Engineering Intelligent Construction and Operation,Tianjin University,Tianjin 300350,China;Center of Construction Management and Quality and Safety Supervision,Ministry of Water Resources,Beijing 100038,China)
出处
《水力发电学报》
北大核心
2025年第12期40-51,共12页
Journal of Hydroelectric Engineering
基金
国家重点研发计划(2023YFC3209404)
天津大学水利工程仿真与安全国家重点实验室基金项目(HESS-2227)。
关键词
引水式水电站
进水口
L型导沙坎
水力特性
防沙效果
数值模拟
动床模型试验
diversion-type hydropower station
water intake
L-shaped sediment diversion sill
hydraulic characteristics
sediment exclusion effectiveness
numerical simulation
movable-bed physical model experiments
