Nonlinear Model For Aggradation in Alluvial Channels

Abstract

A nonlinear parabolic model for aggradation processes in alluvial rivers or channels is presented. A general exponential formula for the sediment transport relation is postulated to account for the nonequilibrium process. An indirect method for evaluating the coefficients of the sediment transport relation is described. The technique is illustrated by numerical experiment and comparison with data. Analytical expressions obtained from perturbation solutions of the characteristic parameters relevant to the aggradation process are derived. The validity of the model is assessed by comparing the analytical and numerical results with available experimental data. Good agreement is obtained.