Study On Large-scale Channel Diversion And The Key Technologies Of Construction Closure

Closure plays a key role in the construction of water resources and hydropower projects, People usually pay more attention to its security, economy and application. River closure is of complicated system engineering, it directly dominates the time, investment and profit of a project. From the development trend of river closure, high head river closure will become popular in the future. Because of the development of transportation and crane, high head river closure becomes a reality. But it brings more difficulties in water closure. As an influential hydraulics parameter of closure gap, it is changing all the time in end-dump closure, and it is always changing. Before implementation water closure, We gain all the hydraulic parameters of closure gap by numerical simulation, especially doing plenty fully of experiments and reasonable optimize on cross section form and size of closure gap, will can effective control the entire process of closure, and may arise the contingency of adverse situations, after this we can plan to do a good job. And then, we can take timely necessary and effective engineering measures in order to avoid unnecessary loses or failure of closure.In this paper, under the premise at the conclusion of the technology of construction closure at home and abroad, to solve the cross-section for the purpose of closure gap, by using the hydraulic calculation method, in the process of construction closure, the changes in hydraulic parameters of closure gap in analysis and research. Specific application as follows: firstly; mold of open channel diversion combined with spilling on closure gap will be established; secondly, with the help of CFD software, the forms of cross section of closure gap (trapeziform and triangle form) will be discussed separately; thirdly, work out the velocity and pressure of the flow on the closure gap and finally find out the best cross section.In the end, by using the upwards results, the author will prove the data of the experimentation is consistent with real situations of the Three Gorges and analyze the trapeziform and triangle form subsequently.