双戗堤截流方式要求上下戗堤分担落差以减小截流难度，但实际应用中水力条件常常难以控制而影响落差分配效果。应用CFD数值模拟方法，对概化边界下双戗堤截流过程进行三维试验研究，探讨上下戗堤之间的平面流态对水力条件和落差分配的影响。结果表明：在上戗堤龙口后促使主流转折造成左右岸逆向双回流的平面流态对下戗分担落差很有必要，采用挑流方式可有效地控制这种流态，但挑流设施的位置和尺寸对流态的形成与稳定有影响，而戗堤间距在稳定的双回流流态下对落差及其分配的影响则较小。

Double dikes can be used to alleviate difficulties in river closure under high flow and big drop. Both dikes are required to share water drop during the closure process. However, in practice, it’s not easy to control the hydraulic conditions to obtain satisfactory results. A series of 3-D numerical experiments were conducted by CFD (Computational Fluid Dynamics) simulation on double-dike closure in simplified straight boundaries. The results demonstrated that two recirculation zones in reverse directions in the flow pattern, which were formed due to main stream diversion between the dikes, were necessary for the drop sharing of the downstream embankment. Through computational tests, the hydraulic diversion were found  to be capable of controlling this kind of stable flow pattern. The location and size of the diversion wall could influence the formation and stability of the flow pattern. In the presence of the two stable recirculations, the distance between two dikes had a minimum value for maintaining the recirculation but had less influences on the total drop and its allocation on the two embankments.