Development of Bed Ridges in Open Channels and their Effects on Secondary Currents and Wall Shear

• Main Authors: Kamran Ansari, Ashfaque Ahmed Memon, Naeem Aziz Memon
• Format: Article
• Language: English
• Published: Mehran University of Engineering and Technology 2012-07-01
• Series: Mehran University Research Journal of Engineering and Technology
• Subjects: Open Channels; CFD Modelling; Ridges; Boundary Shear Stress; Secondary Currents.
• Online Access: http://publications.muet.edu.pk/research_papers/pdf/pdf666.pdf

A numerical analysis of the ridges on the bed of wide, open channels and their effects on the distribution of secondary currents and wall shear is undertaken using CFD (Computational Fluid Dynamics). The presence of the lines of boil, consisting of low speed streaks, periodically in the transverse direction, is reported in the literature due to the presence of the ridges. In the present work, simulations are run on channel sections with varying the number of ridges on the bed and the size of these ridges. The effect of these variations on the flow structures and shear stress distribution in wide open channels is reported. The results offer an interesting insight into the 3D (Three-Dimensional flow structures involved and the link between flow structures and bed morpho-dynamics in prismatic channels.