DOI: 10.1615/TSFP2
LARGE EDDY SIMULATION OF SECONDARY FLOWS OVER LONGITUDINALLY-RIDGED WALLS
SINOPSIS
In the present paper large-eddy simulations of a turbulent channel flow with longitudinal, large-amplitude ridges are carried out. This flow exhibits large secondary flows over the ridge that need to be properly simulated in order to evaluate with enough accuracy the spanwise distribution of the primary as well as the secondary wall stress. The DNS avalaible data at a low Reynolds number as well as the data from an experimental study at a moderate Reynolds number are matched. Our LES results agree satisfactorily with the DNS data at Reτ = 140, and with the experimental data at Reτ = 582. The present investigation shows that the intensity and topology of the secondary flow is dependent on the Reynolds number of the flow. The results have also shown the presence of near-wall, small and intense re-circulations which may produce localized secondary wall stresses.