Turbulent characteristics of densely flexible submerged vegetated channel

Abstract

Turbulent characteristics for dense arrangement of vegetation were analysed based on the experiment performed in tilting flume with bed covered by artificial vegetation, arranged in a regular staggered configuration simulating the open channel flow conditions. This study is basically converged on determination of turbulent characteristics in mixing layer zone. In results turbulent velocity profiles, Reynolds stresses, turbulent intensities, quadrant analysis, budget components, dissipation, length scales and stream power are obtained. The mean deflected plant height is taken as the roughness parameter while calculating results. A significant feature is obtained in velocity profile near the shear instability zone. Turbulent intensities and Reynolds stresses are maximum near to the top of the canopy. Quadrant analysis shows that sweep and ejection events are more dominating factors in submerged vegetated channel.

Keywords:

• Open channel flow
• turbulent flow characteristics
• vegetated boundary
• shear instability
• vegetation density

Acknowledgement

Authors gratefully acknowledge Ministry of Earth Sciences, Government of India sponsoring the project titled ‘Resistance Characteristics of mobile bed Vegetation (MoES/ PAMC/ H&C I 26 I 20 13-PC-ll)’.