A Transition Flow Regime on Stepped Spillways the Facts
نویسنده
چکیده
The stepped channel design have been used since more than 3,000 years. It is understood that low flows behave as successions of free-jets (i.e. nappe flow) while large discharges skim over the pseudo-bottom formed by the step edges. For a range of intermediate flow rates, a transition flow regime takes place. The dominant feature is stagnation on the horizontal step face associated with significant splashing and a chaotic appearance. New criteria for the changes in flow regimes are presented. Transition flows are characterised by significant air entrainment and flow instabilities.
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