Design of scaled movable bed experiments using numerical models

Scaling designs for mobile bed short wave experiments have been analysed using a suite of numerical models to test different sediment scaling configurations. The numerical simulations have revealed that geometrical sediment scaling gives similarity in the boundary layer flow but the sediment transport mode switches from bedload in the prototype to suspended-load in the model. This is due to the high relation of prototype to model sediment sizes. However, scaling to maintain the relative fall speed allows smaller sediment size relations and closer similarity in the dominant transport processes. A set of corrections have been proposed to minimise the scaling effects in sediment transport rates and bottom evolution.