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A41M-03:
Atmospheric Surface Layer Flow over Distributions of Cubes and Evaluation of Transient Dynamics

A41M-03:

Atmospheric Surface Layer Flow over Distributions of Cubes and Evaluation of Transient Dynamics

Thursday, 18 December 2014: 8:30 AM

##### Abstract:

The vertical transition from roughness sublayer to inertial layer is a well-established concept in turbulent boundary layer flows over complex topographies. The transition occurs at approximately three times the canopy height, below which the turbulence statistics resemble a turbulent mixing layer. Turbulent momentum fluxes in `canopy turbulence’ or `obstructed shear flows’ (Ghisalberti, 2008*JFM*

**641**, 51—61) are typically dominated by turbulent sweep events (downward excursions of high momentum fluid), owing to the presence of coherent motions that occupy the region of fluid above the canopy. We have used large-eddy simulation with an immersed boundary method to study turbulent flows over a distribution of uniform height, staggered cubes. The computational domain has been designed such that both the roughness sublayer and a region of the inertial layer are resolved. With this, we record vertical profiles of time series of fluctuations of streamwise velocity,