Author(s): Youichi Yasuda; Iwao Ohtsu
Linked Author(s): Iwao Ohtsu, Youichi Yasuda
Keywords: Flow resistance; Stepped flow; Energy dissipation; Stepped spillway
Abstract: The stepped-channel flows are utilized for dissipating energy of steep-channel flows. But, the flow resistance in stepped channels has not been clarified. The flow conditions in stepped channels are mainly classified into two types: The skimming flow is characterized by the formation of eddy on each step, and the nappe flow is characterized by the formations of nappe and air pocket. In this paper, the flow resistance of skimming flow has been systematically investigated under a quasiuniform flow (i. e., equilibrium condition). In order to estimate the equilibrium condition indirectly, the subcritical sequent depth of the hydraulic jump, which is formed immediately downstream of stepped-channel end, has been measured. The flow resistance of skimming flow can be characterized by the eddy in each step, and it has been found that a skimming flow with the channel slopeθ344. 0tan=has a maximum flow resistance.
Year: 1999