Experimental study on interactions between floating debris and intakes vortices of diversion system

The existence and interactions of intake vortices and floating debris in diversion system lead to trash rack blocking, vibration and seriously threats the safety of trash rack. Taking Fengman Hydraulic Station as the experimental object, the article discusses the formation and development process of intake vortices, the interactions between vortices and floating debris, the blocking process of floating debris to trash rack and the relations between blocking state and the increment of head loss through applying the hydraulic model test. The result shows that changes of water levels of intakes will form vortices. The vortices and floating debris exert the coupling effect which makes the vibration destroy to trash rack. Meanwhile, the floating debris in vortices accelerates the blockings and the partial head loss will be drastically increased as well.