Application of the SPH Method to Breaking and Undular Tidal Bores on a Movable Bed

Abstract

Investigation of breaking and undular tidal bores is a challenging problem in river mouths as fluid flows upstream, where significant bed erosion and scour take place under the bore. In this study, smoothed particle hydrodynamics (SPH) was used to simulate the breaking and undular tidal bores on a movable bed. To model the bores, a moving gate was used to block a steady uniform flow in a channel, and bores were consequently generated as a positive surge and propagated upstream. First, results were presented for the breaking and undular bores on a flat bed, looking carefully at velocity and surface profiles, which were compared with available experimental data. Then, the breaking and undular bores were tested in a channel with a movable bed using a previous experimental study of particle motion. The authors show the morphology changes of the bed under the breaking and undular bore. The results show that the SPH method can be successfully used to investigate the dynamics of the tidal bore and its effects on a movable bed.