Oscillating Hydraulic Jump in a Stilling Basin

Stilling basins downstream of spillways dissipate energy upstream of flow contacting the natural riverbed. This flow sometimes results in the formation of hydraulic jump. Hydraulic jump forms when flow transitions from supercritical to subcritical flow and contains turbulent, chaotic flow with a large amount of headloss. In the Hydrodynamics Laboratory of Michigan Technological University temporally oscillating flow was observed in which the hydraulic jump in the stilling basin would alternate between being drowned and being washed out in an oscillating, cyclical process. This occurred even though the mean flow was steady and not fluctuating.