DOI: 10.1615/TSFP5
IDENTIFICATION OF HAIRPIN-TYPE FLOW STRUCTURES IN SEPARATED FLOW BEHIND A THREE-DIMENSIONAL HILL USING POD
SINOPSIS
The characteristics of large-scale, periodic features associated with separation behind a three-dimensional hill-shaped obstruction in a duct are explored using proper orthogonal decomposition (POD) and extended POD, with particular emphasis being placed on the question of whether or not these features depend on the Reynolds number. Despite the wide range of Reynold number investigated (Re = 1300, Re = 13,000 and Re = 130,000), significant similarities among corresponding low-order POD modes and in the flow structure of the reconstructed flow fields for the three flows are found. These suggest a single mechanism for the formation of large-scale features associated with periodic shedding, regardless of the Reynolds number. The POD spectra also show strong similarities, especially above Re=13,000.