Boundary layer flows over (a) smooth and (b) rough surfaces.

Turbulent Boundary Layers Over Multiscale Rough Patches

Skin friction coefficient distribution along the wall for the 480 × 240

Hydrodynamically Smooth and Rough Boundaries - Compressible Flow

Superhydrophobic drag reduction in turbulent flows: a critical review

If flow separation occurs, does it always accompanies a wake region? I mean, behind the flow separation, does the region always have a wake region whose pressure is low? - Quora

Drag and Lift in Fluids - The Engineering Projects

What would an ideal location be for wind turbines? How far should they be from the town? - Quora

Law of the wall - Wikipedia

Is there any standard elevation (above sea level) requirement in putting up wind turbines? - Quora