The possibilities of reducing the drag in pipes with a circular cross section by lining them with riblets have been investigated experimentally for developed turbulent air flow. The maximum drag reduction of 6–7% in the riblet-lined as compared with the smooth pipe was obtained for a dimensionless riblet pitch, expressed in law-of-the-wall parameters,s+=14−18.
KeywordsFluid Dynamics Drag Reduction Circular Cross Section Maximum Drag Reduction Smooth Pipe
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