On Velocity Spectra within the Wake behind a Circular Cylinder

Abstract

The canonical case of a circular cylinder in crossflow is studied experimentally at Reynolds number 5k. The power-spectra of all velocity components in the turbulent wake are studied in detail. Special attention is paid to the appearance of peaks and spectra shape, i.e., to the slope of spectra parts. Signatures of presence forward energy cascade and inverse enstrophy cascade are detected. Three peaks corresponding to 1st, 2nd and 3rd harmonics of the Strouhal frequency are detected as well as local spectra slopes conforming to the Kolmogorov and Kraichnan theories.