三峡工程导流底孔水力学研究与运用  

Model study and prototype application of diversion outlet design for Three Gorges project

作　　者：王才欢[1] 杨文俊 周赤[1] 王列[1] 侯冬梅[1] 

机构地区：[1]长江水利委员会长江科学院,武汉430010 [2]长江水利委员会国际合作与科技局,武汉430010

出　　处：《水力发电学报》2009年第6期65-70,共6页Journal of Hydroelectric Engineering

摘　　要：三峡工程导流底孔承担三期导截流和围堰挡水发电期泄洪任务,运用水头高、变幅大,导流流量达70000m3/s,运行条件复杂,为国内外导流工程罕见。在三峡工程三期截流过程中,导流底孔要满足截流流量9010m3/s时落差小于3.5m;导流底孔下泄流量17600m3/s时,三期土石围堰要求上游水位不超过85.0m;为避免右岸基坑在施工过程中被淹,导流底孔与深孔联合泄流30100m3/s时水位不超过98.0m;在围堰挡水135m水位发电期,导流底孔与其它过水建筑物的总泄流能力要大于70000m3/s,等等。针对导流底孔各运行阶段的水流特点,系统研究了长管、短管布置方案的截流落差、底孔明槽流态及下游水流衔接、高速水流引起的空化空蚀以及因导流底孔位置较低引起泥沙磨损等,分别提出了能够兼顾导流底孔各运行阶段水力学要求的长管和短管布置方案。在长管布置方案被用于原型工程之后,导流底孔经受了各阶段设计洪水的运行考验,历时3年多,工程运行安全,取得了完好的工程效果。The diversion bottom outlets of Three Gorges project are used for flow diversion at the third construction stage and for flood releasing at the initial cofferdam-supported-generation stage. These outlets are quite unusual in the world for their high water head, large variation range of water level, huge diversion flow（70 000m3/s） and complex operations. The construction of third stage requires that the cut-off drop is less than 3.5m for cut-off flow 9 010m3/s, the upper level below 85.0m for the total flow 17 600m3/s of bottom outlets to operate the cofferdam and below 98.0m for the total flow 30 100m3/s of bottom diversion outlets and deep outlets to avoid flooding of the right bank foundation ditch. Besides, at the initial cofferdam stage of upper level 135m, the total flow of bottom outlets and other overflow structures must be below 70 000ma/s. With consideration of these conditions required by all the stages, a systematic model study was conducted for cut-off drop, open channel flow of the bottom outlets and downstream flow engaging, cavitations of the high speed flows and sediment wearing on these low position outlets. This study focuses on two schemes, long-tube scheme and short-tube scheme. Through the study, feasible long-tube and short-tube schemes that meet the hydrodynamic requirements at all the stages were proposed. The long-tube scheme was adopted in the Three Gorges prototype. The protot：pe operation of these bottom diversion outlets under the flood of each stage in the three years shows a satisfactory flow condition and a perfect result.

关 键 词：水力学 导流底孔布置 截流和导流 泄洪度汛 三峡工程 

分 类 号：TV135.2[水利工程—水力学及河流动力学]