C. Jin, I. Potts, D. C. Swailes, M. W. Reeks 36 340 350 360 370 380 tu$_{g}$/D 1.0 0.5 0.0 0.5 1.0 u ′ /u g ,v ′ /u g ( a ) u ′ /u$_{g}$ v ′ /u$_{g}$ 10 -2 10 -1 10 0 10 1 10 2 fD/u$_{g}$ 10 -8 10 -7 10 -6 10 -5 10 -4 10 -3 10 -2 10 -1 10 0 Power Spectra Density (PSD) Strouhal frequency ( b ) u ′ v ′ k = − 5 / 3 Fig. 13: Time histories of velocity signal fluctuations behind cylinder C3 and the corresponding power spectrum density.