Wake Oscillator Model Proposed for the Stream-Wise Vortex-Induced Vibration of a Circular Cylinder in the Second Excitation Region

A wake oscillator model is presented for the stream-wise vortex-induced vibration of a circular cylinder in the second excitation region. The near wake dynamics related to the fluctuating nature of alternate vortex shedding is modeled based on the classical van der Pol equation. An appropriate approach used in cross-flow VIV is developed to estimate the model empirical parameters. The comparison between our calculations and experiments is carried out to validate the proposed model. It is found that the present model results agree fairly well with the experimental data.