Velocity Distribution and Bed Profile Variation for Inbank Flow in a Meandering Channel

Abstract

Meandering is relatively a common river planform in Malaysia. The sediments transported along the channel due to erosion and deposition are the main reason of meandering river formation. This resulted when the outer bend experienced higher velocities while lower velocities occurred at the inner bend which resulting in sedimentation processes along the river. Hydraulic characteristics in meandering river are considerably more complex and unique as compared to the straight river. Therefore, an experimental investigation was conducted in the Hydraulic Laboratory, UTM Johor Bahru to enhance the understanding of the hydraulics behaviour and morphological changes of an inbank flow in a sand bed meandering channel. Flow classification, streamwise velocity distribution and bed profile changes are addressed in this paper. The findings prevailed that the maximum velocity reduced up to 10% from the upstream to downstream due to the resistance from the meanders. Furthermore, erosion and deposition processes along the channel highly influenced by the velocity distribution. The maximum velocity shifted toward the outer and decreased at the inner of the meander resulting in the deposition and erosion. Higher erosion and deposition were observed at the outer and inner bends, respectively during high flow discharge.