Bubble entrainment, spray and splashing at hydraulic jumps

Hydraulic jumps: turbulence and air bubble entrainment

-A free-surface flow can change from a supercritical to subcritical flow with a strong dissipative phenomenon called a hydraulic jump. Herein the progress and development in turbulent hydraulic jumps are reviewed with a focus on hydraulic jumps operating at large Reynolds numbers typically encountered in natural streams and hydraulic structures. The key features of the turbulent hydraulic jumps...

Two-dimensional bubble clustering in hydraulic jumps

Air entrainment and turbulent fluctuations in hydraulic jumps

A hydraulic jump is the sudden transition from a high-velocity impinging flow into a turbulent roller in an open channel. Substantial amounts of air are entrapped at the impingement point, and significant free-surface fluctuations take place above the roller. In the present study, some physical modelling was conducted in a relatively large sized facility. The flow conditions included a wide ran...

Hydraulic jumps at boundaries in rotating fluids

We consider three-dimensional hydraulic jumps (shocks) propagating along boundaries in rotating fluids. This study is motivated by earlier work (Fedorov & Melville 1995), which dealt with the evolution to breaking of nonlinear Kelvin waves. We obtain the jump relations and derive an evolution equation for the jump as it propagates along the boundary. It is shown that after some initial adjustme...

Air Entrainment and Turbulence in Hydraulic Jumps: Free- Surface Fluctuations and Integral Turbulent Scales

An open channel flow can change from a supercritical to subcritical flow with a strong dissipative process: a hydraulic jump. Herein some new measurements of free-surface fluctuations next to the jump toe and integral turbulent scales in the roller are presented with a focus on turbulent hydraulic jumps with a marked roller. The results highlighted the fluctuating nature of the impingement peri...