Rapidly Varied Flow

Rapidly varied flow is a nonuniform flow with the water depth changing significantly over a relatively short distance. Accordingly, the loss in energy due to the boundary friction is generally small and can be neglected. Rather, most of the head loss within the flow is caused by the high turbulence. For this case, the pressure distribution within the flow cannot be assumed hydrostatic as the streamlines are highly curved. An example of a rapidly varied flow is the hydraulic jump.

Hydraulic Jump A hydraulic jump occurs in the transition from supercritical to subcritical flow (Figure 1.3). The depths of flow upstream and downstream of the jump are called conjugate depths. The transition between supercritical and subcritical flow results with an effective energy loss that cannot be neglected. Owing to the complex internal flow pattern with energy losses