Turbulent flows over dense filament canopies

Turbulent Pressure and Velocity Perturbations Induced by Gentle Hills Covered with Sparse and Dense Canopies

How the spatial perturbations of the first and second moments of the velocity and pressure fields differ for flow over a train of gentle hills covered by either sparse or dense vegetation is explored using large-eddy simulation (LES). Two simulations are investigated where the canopy is composed of uniformly arrayed rods each with a height that is comparable to the hill height. In the first sim...

Turbulent Flow over Cars

In this paper the flow behaviour over a number of car bodies is studied. For this purpose the unsteady 2-D incompressible Navier-Stokes equations have been applied. After averaging and nondimensionalizing the equations, the system of equations has been transformed from the Cartesian (x-y) coordinates to a body fitted generalized (-) coordinate. As the flow is incompressible, the density in the ...

Predicting the roughness length of turbulent flows over landscapes

Introduction Conclusions References Tables Figures Back Close Full Screen / Esc Abstract Introduction Conclusions References Tables Figures Back Close Full Screen / Esc Abstract The fully rough form of the law of the wall is commonly used to quantify velocity profiles and associated bed shear stresses in fluvial, aeolian, and coastal environments. A key parameter in this law is the roughness le...

Modeling unsteady turbulent flows over ripples: RANS versus LES

Optimal control of katabatic flows within canopies

What slope angle favours the development of katabatic flow is still an open question. Some studies have clarified that katabatic winds are stronger on steep slopes, while others have demonstrated that katabatic winds are stronger on gentle slopes. Here, we explore the control mechanisms of katabatic flow using a simplified theoretical model in an attempt to clarify the causes of the paradoxical...