双戗堤立堵进占截流龙口水力参数变化规律的研究

龙口流速和单宽功率是衡量截流困难度的两个重要指标，了解其变化规律对截流设计和施工都有极大的意义。本文从两个戗堤在截流中的作用出发，以落差分配为控制条件，通过理论分析，并结合模型试验。对整个截流过程中两个龙口的流速和单宽功率的变化规律进行了较为深入的研究，首次对双戗堤上堵进占截流两参数的变化进行了全面的阐述，为双戗堤上堵进占截流的实施提供了可靠的判断依据。

Research on the Hydraulic Characteristic During River Closure End-tipped With Two Banks

Both the flow velocity and the unit stream energy are the indexes to evaluate the degree of difficulty for the river closure.Based on the basic theory of hydraulics,from the functions of the two banks in end-tipped closure with two banks,the thesis analysed the varying regularity of both the velocity and the unit stream energy,The model test proved that the most difficult period for the closure is related to flow conditions in the gap.It may occur at the critical flow,or at the time that the triangle section is being formed,or at the moment that Z/Zm is 0.7 to 0.9.