Large-eddy simulation of highly-disturbed turbulent flows in a V-shaped rib-roughened duct

In this paper, highly-disturbed turbulent flows confined within a duct with equally spaced V-shaped ribs mounted on one wall are investigated using large-eddy simulation (LES). Two different inclined V-shaped (60° and 45°) rib cases are studied in comparison with the perpendicular (transverse) rib case. The results indicate that secondary flow appears as a pair of streamwise elongated vortices in all the cases, and its strength increases monotonically as the rib angle decreases. The effects of different shaped ribs on turbulence kinetic energy (TKE), TKE production rate and coherent structures are systematically investigated.