NUMERICAL SIMULATION ON LOCAL SCOUR BELOW A WEIR USING EQUILIBRIUM, NON-EQUILIBRIUM MODELS AND DEM FOR SEDIMENT-TRANSPORT

Abstract

In this study, numerical simulations using equilibrium, non-equilibrium models and DEM for sediment- transport were performed for local scour below a weir. First, the coupling technique between the vertical 2D flow model introduced with the FAVOR method and DEM was explained. Next, comparisons with the previous sediment-transport formulas and the DEM model were carried out, and the validity of the DEM model was examined. Finally, simulations by each model were performed for initial local scour process below a weir. Consequently, the DEM model was able to reproduce the local scour process. Moreover, the development speed of the local scour by the non-equilibrium sediment-transport model was slow. Therefore, it was pointed out that the model is not suitable for prediction of this phenomenon.