On vortex shedding from a circular cylinder in the critical Reynolds number régime

Abstract

The flow around a circular cylinder has been examined over the Reynolds number range 10⁵ to 7·5 × 10⁵, Reynolds number being based on cylinder diameter. Narrow-band vortex shedding has been observed up to a Reynolds number of 5·5 × 10⁵, i.e. well into the critical régime. At this Reynolds number the Strouhal number reached the unusually high value of 0·46. Spectra of the velocity fluctuations measured in the wake are presented for several values of Reynolds number.