Separation and pattern formation in hydraulic jumps

We present theory and experiments on the circular hydraulic jump in the stationary regime. The theory can handle the situation in which the fluid flows over an edge far away from the jump. In the experiments the external height is controlled, and a series of transitions in the flow structure appears. First the steepening of the jump causes a transition akin to the breaking of a wave, and subsequently a series of shapes appear, which break the azimuthal symmetry.