ABSTRACT

A coupled (hydrodynamics and sediment transport) two-dimensional numerical model is formulated based on the source code of Telamac-2D model and validated against the experimental data before applying it to a natural meander bend of Gowain River located in North-eastern part of Bangladesh. Impermeable groynes at 90° and 120° to the bank were implemented to examine their effect on modifying the near-bank hydro-morphological phenomena. Both orientation, reduced the near bank velocity and bed shear stress. Groynes oriented at 90° were more effective in shifting the high-velocity away from the banks but could promote greater erosion behind the initial groynes at the entry of the bend. On the other hand, groynes placed at 120° induced greater deposition around the initial groynes. Therefore it is suggested that rather than adopting a single orientation, a combination of two or more arrangements would enhance the effectiveness of the groynes.