Present study discusses tidal currents, sediment transportation and channel changes with sand bar defor-mation by means of numerical simulation in Sittaung river estuary where very fine sediment with average diameter of about 0.03 mm dominates. In order to treat sediment erosion on the channel bed composed of very fine sediment, a new formula of erosion rate is introduced into conventional, depth averaged two dimensional models for tidal currents, sediment transportation and associated bed evolution. The computed results suggest that tidal currents including the tidal bores, bar formation processes and channel bifurcations are evaluated by means of the proposed model. |