SEPARATION AND PATTERN-FORMATION IN HYDRAULIC JUMPS

We present theory and experiments on the circular hydraulic jump in th e stationary regime. The theory can handle the situation in which the fluid flows over an edge far away from the jump. In the experiments th e external height is controlled, and a series of transitions in the fl ow structure appears. First the steepening of the jump causes a transi tion akin to the breaking of a wave, and subsequently a series of shap es appear, which break the azimuthal symmetry. (C) 1998 Elsevier Scien ce B.V. All rights reserved.