Author(s): S. Karki; H. Nakagawa; K. Kawaike; Eddy J. Langendoen
Linked Author(s): Kenji Kawaike, Hajime Nakagawa
Keywords: No Keywords
Abstract: Hydro-morphological response of the meandering channels to different arrangement of groynes is investigated using a depth-averaged 2D numerical model. A coupled model of flow and bed morphology is formulated and validated before applying to two laboratory scale sine-generated meandering channels of different sinuosity and deflection angle. Two positions- one starting exactly from the outer bank apex and the other starting from downstream of the outer bank apex and two orientation-one at 90° and the other at 120° to the bankline were investigated. Results revealed that in low sinuosity channel, groynes positioned downstream of the outer bank apex whereas in higher sinuosity channel groynes at apex are more effective in reducing the scour depth at the groynes tip, shifting high-velocity and high near-bank shear stress away from the banks. The analysis also showed that the morphology and flow field were more sensitive to the change in groynes position than their orientation.
Year: 2020