Turbulent kinetic energy in the upstream of Piano Key Weir

摘要

The protrusion of a hydraulic structure con- structed in a river bed disturbs the flow and sediment transport. It is very important to investigate the changes on micro-flow behavior (turbulent) from sediment transport point of view. In this paper an attempt has been made to investigate the change in flow turbulent kinetic energy along the flow depth with and without Piano Key Weir (PKW; a type of labyrinth weirs) and try to establish a distribution pattern of turbulent kinetic energy with respect to relative depth. Here, relative depth is defined as ratio of depth of point of measurement and depth of flow. Flow resistance has been increased after introduction of PKW in channel. Turbu- lent kinetic energy has been fitted with Gaussian distribution of higher order as flow resistance increased. After introduc- tion of PKW in channel, velocities slow down but shifting of centroid indicates relative ease of passing particles through sloping keys.