Fully developed turbulent channel flow with a blade riblet surface has been simulated numerically at Reynolds number Reτ ≈ 210 by Large Eddy Simulations (LES). The blade riblet is shown to provide a total viscous drag reduction approximately 9% with the riblet spacing s+ =16.9 and the cross section Ag 1/2=11.6. For the sake of investigating the interaction of the turbulent flow with riblets, the mean velocity profiles, velocity fluctuations, and instantaneous flow visualization have been analyzed. It has been found that the riblet of certain size reduces drag by damping the dynamics and weakening the cross motions in the near-wall boundary layer, revealing beneficial turbulence controlling.
|Number of pages||5|
|Journal||Applied Mechanics and Materials|
|Publication status||Published - 2012|