Flow-induce motions (FIM) small-scale model tests were performed for the Jappaku floating offshore wind turbines (JPK), a FOWT developed to operate in Brazilian waters. This paper aims to investigate the presence of FIM on the JPK to show the importance of heave plate (HP) design and to show how HP mitigates FIM.
Three different HP dimensions were tested and compared with the condition without HP. In addition, two different incidence angles of the current were tested, namely, 0 deg and 180 deg. The results showed amplitudes in the transverse direction similar to the diameter of the external platform column for the case without HP.
These amplitudes are higher than the ones observed for previous deep-draft semi-submersibles found in the literature. Conversely, the largest HP dimensions implied in mitigation of the FIM amplitudes, i.e., very low amplitudes, were observed.
The presence of the central column played an essential role in FIM and significantly modified the amplitudes in different current incidences. Due to the different diameters of the external and central columns, the FIM presented two different branches of response related to the vortex-shedding frequency around the columns.
The results showed that significant FIM could occur for this specific JPK investigation even with HP. The HP design has a positive effect on reducing dynamic behaviors due to the wave and current incidences. Therefore, its design must be included in the preliminary stages of FOWT developments. [DOI: 10.1115/1.4056345]
flow-induced motions (FIM), floating offshore wind turbines (FOWT), model tests, design of offshore structures, fluid–structure interaction, vortex-induced vibration
Rodolfo T. Goncalves ̧ 1
OSPL—Ocean Space Planning Laboratory, Department of Systems Innovation, School of Engineering, The University of Tokyo, Bunkyo-ku, Tokyo 113-8656, Japan
e-mail: goncalves@g.ecc.u-tokyo.ac.jp
Edgard B. Malta
Technomar Engenharia Oceânica, São Paulo, SP 03178-200, Brazil
e-mail: edgard@technomar.com.br
Alexandre N. Simos
TPN—Numerical Offshore Tank Laboratory, Department of Naval Architecture and Ocean Engineering, Escola Politecnica, University of São Paulo, ́
São Paulo, SP 05508-030, Brazil
e-mail: alesimos@usp.br
Shinichiro Hirabayashi
OSPL—Ocean Space Planning Laboratory, Department of Ocean Technology, Policy, and Environment, School of Frontier Sciences,
The University of Tokyo, Kashiwa-shi, Chiba 277-0882, Japan
e-mail: hirabayashi@k.u-tokyo.ac.jp
Hideyuki Suzuki
OSPL—Ocean Space Planning Laboratory, Department of Systems Innovation, School of Engineering, The University of Tokyo,
Bunkyo-ku, Tokyo 113-8656, Japan
e-mail: suzukih@sys.t.u-tokyo.ac.jp