Coherent shedding from a circular cylinder at critical, supercritical, and transcritical Reynolds numbers

Results are summarized from NASA-Langley studies of the mean drag and unsteady flow parameters of the flow around a circular cylinder at critical, supercritical and transcritical Re. Flow velocities of Mach 0.05-0.40 in the Low Turbulence Pressure Tunnel were used in conjunction with Re from 250,000-6.2 million. Data were collected in the wake and along the walls using pressure transducers. Corrections which were devised to calculate the Strouhal numbers in the presence of broadband signatures in the supercritical regime are described. The tests revealed, as found in previous tests, a discontinuity in the Strouhal number (from 0.2-0.43) in the supercritical regime.