闸坝防冲护坦末端淘刷对水流流态影响研究  

Study on Effect of Scouring at the End of Dam Apron Foundation on Flow Pattern of Water

作　　者：雷茜茹 汪振 张法星[1] 蔡爱玲 LEI Qian-ru;WANG Zhen;ZHANG Fa-xing;CAI Ai-ling(State Key Laboratory of Hydraulics and Mountain River Engineering,Sichuan University,Chengdu 610065,China;PowerChina Huadong Engineering Corporation Limited,Hangzhou 311122,China;Chongqing Vocational College of Transportation,Chongqing 402247,China)

机构地区：[1]四川大学水力学与山区河流开发保护国家重点实验室,四川成都610065 [2]中国电建集团华东勘测设计研究院有限公司,浙江杭州311122 [3]重庆交通职业学院,重庆402247

出　　处：《水电能源科学》2023年第5期166-169,共4页Water Resources and Power

基　　金：国家自然科学基金重大项目(52192673);国家自然科学基金重点项目(51939007)。

摘　　要：采用急流衔接的闸坝防冲护坦末端“软硬”交界处或预挖冲坑常常发生基础淘刷破坏,不仅使护坦处于悬空状态,还可能引起护坦末端水流流态与设计的急流流态有偏差,甚至形成水跃状大尺度旋滚淘刷河床,但相关研究成果很少。针对闸坝下游防冲护坦末端基础发生淘刷的情景,采用室内机理模型试验和三维湍流数值模型方法,对护坦末端不同尺寸概化淘刷坑附近的水流流态进行详细观测和计算分析。结果表明,与护坦末端基础未被淘刷时的急流流态相比,淘刷坑使水流流态发生很大变化,可分为护坦上游的水跃、淘刷坑内的混合流、此两类组成的准周期流态三种。流态演化的研究结果可为分析闸坝下游护坦结构大规模破坏提供技术支持,具有一定工程应用价值。The"reinforced concrete shield and riverbed"junction or pre-excavated pits at the end of the apron of a gate dam with supercritical flow connection mode are often damaged by foundation erosion,which not only leaves the apron in a suspended state,but may also cause the flow pattern at the end of the apron to deviate from the designed supercritical flow pattern,or even form a hydraulic jump like large-scale rolling and scouring riverbed,but there are few relevant research results.For the scenario that suspended foundation at the end of apron caused by local generalized scouring,the detailed observation and computational analysis of the flow patterns near the scour pits of different sizes at the end of the apron were carried out using physical model experiments and three-dimensional turbulence numerical modelling methods.Compared to the supercritical flow pattern at the end of the apron when the foundation is not scoured,the results show that the scour pits change the flow pattern significantly,and can be divided into three categories.The first category is the hydraulic jump upstream of the apron,the second category is the mixed flow in the scour pit and the third category is the quasi-periodic flow pattern consisting of the first two categories.The results of the flow evolution study can provide technical support for the analysis of large-scale damage to the retaining structure downstream of the dam apron,which has certain engineering application value.

关 键 词：急流衔接 淘刷坑 护坦 水流流态 

分 类 号：TV135[水利工程—水力学及河流动力学]