Numerical Research about Drag-Reduction Characteristic of Riblet Structure on Aerofoil Blade of Centrifugal Fan

The drag reduction characteristics of riblet structure on aerofoil blade of centrifugal fan were numerically simulated with Fluent. Riblet structure still has good drag reduction effect on the surface of aerofoil blade. The best drag reduction effect has been gotten with appropriate riblet structure size, with the greatest drag reduction efficiency of 9.65%. And under the design flow of the fan, the drag can be reduced by 2.96%. The mean velocity of near-wall region on riblet surface has a significant increase than smooth surface. Turbulent kinetic energy and turbulent intensity are lower than smooth surface obviously, the drag reduction effect of riblet structure on aerofoil blade is verified. The present results can be used to provide a valuable reference for optimization of centrifugal fan blade modification.