Author(s): Hariom Gautam; Anirban Mandal; Zulfequar Ahmad; Pramod Kumar Sharma
Linked Author(s): Pramod Kumar Sharma
Keywords: Velocity Distribution Local Scour Individual Flexible vegetation Turbulence
Abstract: Vegetation in waterways alters flow by modifying velocity distributions, inducing turbulence, and increasing flow resistance. These changes result in the formation of bedforms, such as scour zones and sediment deposition patterns, which shape channel morphology. The present laboratory study investigates the effects of individual submerged flexible vegetation on turbulent flow and sedimentation patterns, including scour and deposition. An artificial flexible plant made of plastic with an irregular shape and non-uniform frontal width was used to replicate natural sedge/grass. The experiments were conducted under different flow conditions for both vegetated and non-vegetated scenarios. An Acoustic Doppler Velocimeter (ADV) was used to measure velocity profiles and turbulence characteristics at various streamwise locations relative to flexible vegetation. Scour and deposition characteristics around the flexible vegetation were measured using an ultrasonic bed profiler. The vertical streamwise velocity profile exhibits an ‘S’ shape, with minimum velocity observed in the leafage area where the frontal width was maximum. Maximum turbulence quantities were recorded near the canopy top. The depth and volume of the scour hole increased with higher flow rates, along with higher sediment deposition.
Year: 2025