Flow structure inside and around a rectangular array of rigid emerged cylinders located at the sidewall of an open channel

Flow structure inside and around a rectangular array of emerged cylinders located adjacent to the sidewall of an open channel is investigated using eddy-resolving numerical simulations. This configuration is particularly relevant for understanding how patches of aquatic vegetation developing near a river's banks affect flow and transport. The array of width W = 1.6D and length L = 33D-35D (D is the flow depth) contains rigid cylinders. Simulations with incoming, fully developed turbulent flow (channel Reynolds number, Re-D = 12 500) are conducted with different values of the solid volume fraction (0.02 0.5, mean-flow recirculation bubbles form behind the array. For constant aW, the total size of the region containing recirculation bubbles decreases with increasing d/D. Simulations results are used to quantify the effect of varying phi, aW, d/D and the cylinders' shape on the streamwise decay of the mean streamwise velocity inside the array, turbulent kinetic energy distribution, mean streamwise drag forces acting on the cylinders and mean streamwise drag coefficients.


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Citation Formats
M. Köken, “Flow structure inside and around a rectangular array of rigid emerged cylinders located at the sidewall of an open channel,” JOURNAL OF FLUID MECHANICS, pp. 0–0, 2021, Accessed: 00, 2021. [Online]. Available: https://hdl.handle.net/11511/88637.