NUMERICAL SIMULATION ON DEVELOPMENT PROCESS OF DUNES AND FLOW RESISTANCE

Abstract

A flow resistance in a river changes with development or attenuation of sand waves. Therefore, it is necessary to know how the flow resistance varies with transformation of sand bed, in order to predict the water surface variations. In this study, the numerical model to reproduce the formation processes of dunes was developed. A depth averaged flow model considering the effects of vertical acceleration and a nonequilibrium sediment transport model is combined. Calculated results on the temporal development processes, the shape characteristics of dunes and flow resistance are compared with previous experimental studies.