Optimization of the Wake Oscillator for Transversal VIV

Journal of Marine Science and Engineering

Ekaterina Pavlovskaia¹  Andrey Postnikov²  Victoria Kurushina³  Guilherme Rosa Franzini⁴ 

[1] Centre for Applied Dynamics Research, School of Engineering, University of Aberdeen, Aberdeen AB24 3FX, UK;Department of Civil, Environmental and Geomatic Engineering, University College London, London WC1E 6BT, UK;Marine, Offshore and Subsea Technology Group, School of Engineering, Newcastle University, Newcastle upon Tyne NE1 7RU, UK;Offshore Mechanics Laboratory, Escola Politécnica, University of São Paulo, São Paulo 03178-200, Brazil;

关键词: vortex-induced vibrations;    VIV;    wake oscillator;    phenomenological model;    rigid structures;    transversal oscillations;   

DOI  :  10.3390/jmse10020293

来源: DOAJ

【 摘 要 】

Vibrations of slender structures associated with the external flow present a design challenge for the energy production systems placed in the marine environment. The current study explores the accuracy of the semi-empirical wake oscillator models for vortex-induced vibrations (VIV) based on the optimization of (a) the damping term and (b) empirical coefficients in the fluid equation. This work investigates the effect of ten fluid damping variations, from the classic van der Pol to more sophisticated fifth-order terms, and prediction of the simplified case of the VIV of transversally oscillating rigid structures provides an opportunity for an extended, comprehensive comparison of the performance of tuned models. A constrained nonlinear minimization algorithm in MATLAB is applied to calibrate considered models using the published experimental data, and the weighted objective function is formulated for three different mass ratios. Comparison with several sources of published experimental data for cross-flow oscillations confirms the model accuracy in the mass ratio range. The study indicates the advantageous performance of the models tuned with the medium mass ratio data and highlights some advantages of the Krenk–Nielsen wake oscillator.

【 授权许可】

Unknown