Hydraulic Jump

A hydraulic jump is a sudden rise in fluid depth in open channels, occurring when high-velocity (supercritical) flow transitions to low-velocity (subcritical) flow. This phenomenon requires an upstream Froude number greater than 1, as flows with Fr₁<1 remain s...

A hydraulic jump is a sudden rise in fluid depth that occurs when high-velocity water transitions to a slower flow. 

This only happens in supercritical flow, where the Froude number exceeds 1. In subcritical flow (a Froude number less than 1)...