Author(s): Michele Trevisson; Marco Ghisalberti; Gregory Ivey
Linked Author(s): Michele Trevisson
Keywords: Canopy flow; Surface velocity; Bed geometry; Flow prediction; Momentum balance
Abstract: Various environmental flows take place over permeable media (here called ‘obstructed shear flows’), such as submerged vegetation, sediment beds and coral reefs. The obstructions greatly differ in shape, size and spatial scales resulting in a range of flow heterogeneities. However, due the flow retardation induced by the drag of the obstructions, these flows share a common hydrodynamic (Kelvin-Helmholtz-type) instability at canopy top. On this basis, Ghisalberti (2009) showed that obstructed shear flows can be treated as hydrodynamically similar systems. Thus, a model is developed here to predict the average in-canopy flow velocity for any obstructed shear flow knowing only the free-stream velocity and the geometric features of the canopy.
Year: 2024