A Model Extension for Vortex-Induced Vibrations
The paper presents free-vibration wind tunnel tests performed at WIST Boundary Layer Wind Tunnel at Ruhr-Universität Bochum (Germany) on a 3D aeroelastic cylindrical model with circular cross-section. The aim of the tests is to validate a model extension to the original spectral method developed by Vickery & Basu, able to calculate the maximum oscillation of a structure subjected to vortex-induced vibration in the lock-in region. The peculiarity of the extension is the implementation of an experimental curve for the negative aerodynamic damping. It was previously developed by the authors through forced vibration wind tunnel tests. The model extension is based on a linear differential equation. In fact, linear – in case iterative – approaches are usually preferred for the design of structures. However, limitations due to linearization of an intrinsically non-linear phenomenon are unavoidable. Strengths and weaknesses of the linear approach are discussed in the paper.
KeywordsCircular cylinder Free-vibration wind tunnel tests Vortex-induced vibrations Vortex shedding Vortex resonance Aerodynamic damping
The first author would like to acknowledge the Alexander von Humboldt Foundation (Germany) for the support to this research and the European Commission’s Framework Program “Horizon 2020”, through the Marie Skłodowska-Curie Innovative Training Networks (ITN) “AEOLUS4FUTURE - Efficient harvesting of the wind energy” (H2020-MSCA-ITN-2014: Grant agreement no. 643167) for the possibility of cooperation.
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