MORPHODYNAMIC CHARACTERISTICS OF A SANDY BED MEANDERING CHANNEL AT DIFFERENT DISCHARGES
DOI:
https://doi.org/10.11113/mjce.v36.23048Keywords:
meandering channel, mobile bed, fixed walls, inbank flow, Manning's n, velocity distribution, morphological changesAbstract
Transportation of sediment is a critical issue in riverine environments, particularly in meandering channels where flow dynamics are complex. However, information regarding erosion and deposition processes in meandering channels is still limited. Therefore, an experimental investigation on the influence of discharge variation on the morphodynamics of a meandering channel has been carried out. The experimental investigation was conducted at the Hydraulic and Hydrology Laboratory, UTM Johor Bahru. The study investigates the flow profiles and the morphological changes of inbank flow conditions represented by shallow and deep flow depths. The findings revealed that Manning’s n in a deep flow depth was 60.12% higher than a shallow flow depth. Moreover, velocity at the channel bend was increased by 8.3% to 14.6% compared to the crossover along the channel. This indicates that the geometrical planform plays a crucial part on the variability of velocity in the channel. Therefore, the outcomes of this study could provide more effective river management strategies to resolve erosion and deposition issues in river engineering studies.
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