On the Engelund–Fredsøe Channel-Stability Problem

Abstract

To settle the Engelund–Fredsoe channel-stability problem, a condition is defined in this paper which makes it possible to determine the value of the phase shift between the flow rate of the sediment load and the maximum of the bottom tangential stresses arising in a turbulent hydrodynamic flow when it flows around gentle shallow periodic waves of low steepness. The dependence of the phase shift for bottom waves of small steepness on the geometric and physicomechanical parameters of the problem is analyzed. For the distribution of shear stresses on the bottom surface, a regularity is established that relates the length of bottom waves to the depth of flow. This pattern generalizes a number of previously obtained phenomenological models and is consistent with known experimental data.