Author(s): Nina Nikora; Vladimir Nikora; Ivano Fadanelli; Maurizio Righetti; Marco Tubino
Linked Author(s): Vladimir Nikora
Keywords: No Keywords
Abstract: In this paper we assess the applicability of the mixing layer analogy for vegetated channels with flow submergence and vegetation density that are much higher than in previously studied cases. This is done by a comparison of measured turbulence properties with those reported for the conventional boundary (CBL, inertial sublayer) and mixing (CML, at the position of the inflection point in the velocity profile) layers, terrestrial canopy flow (TCF, at the canopy top), rough-bed open channel flow (OCF, just above gravel roughness elements), and aquatic canopy flow in a natural stream (ACF1, at the canopy top). The main attention is paid to vertical distributions of normalized values of the longitudinal mean velocity and associated shear turbulence scale, turbulence intensities, correlation coefficient between longitudinal and vertical velocity fluctuations, skewness and kurtosis coefficients, and eddy convection velocities. The analysis also includes an assessment of the effects of flow submergence and the shear-velocity-based Froude number on the shear turbulence scale that could be considered as a measure of mixing layer thickness.
Year: 2010