Fig. 18

Frequency-specific synchronization analysis: phase difference time variation and corresponding overlapped pitch and plunge time histories at \(U_{fold}\) = 7 m/s, \(\alpha _{pre}(^\circ )\) = \(20^\circ\) and \(\overline{\omega }\) = 0.67. (a) original signal, (b) low frequency signal, and (c) high frequency signal.