Author(s): P. Mahesh; V. Deshpande; B. Kumar
Linked Author(s): Mahesh Patel
Keywords: No keywords
Abstract: In this study, an experimental approach is used to observe the effects of downward seepage on flow resistance in a threshold alluvial channel with parabolic cross sectional shape. Experiments are performed over fine and coarse sand bed channels in two categories: no seepage experiment and seepage experiment. Shear velocities are evaluated from the Reynolds shear stress distribution for both sets of experiments. Increase in the value of shear velocity is observed for the seepage experiment. Log-law of the velocity distribution in alluvial channel is modified over rough boundary with parabolic cross-sectional shape of the alluvial channel. The value of von-Karman’s constant is decreased with the application of downward seepage. Increase in turbulent production and decrease in turbulent kinetic energy dissipation are observed in the presence of downward seepage. Further, Darcy-Weisbach friction factor is calculated and increase in the flow resistance is observed under the action of downward seepage.