Principle of Minimum Froude Number

The stability of river channel adjustment toward equilibrium is controlled by a set of factors governed by the Froude number. When the channel is subjected to water discharge, sediment load, and sediment particle size, it tends to attain stability which corresponds to the minimum Froude number and minimum bed material motion. Field observations and computer simulations for sand-bed rivers show that a river in equilibrium tends to acquire a stable geometry with minimum Froude number. This leads to the hypothesis of minimum Froude number, which is presented in this chapter.