Shanghai Jiaotong Daxue xuebao (Jul 2024)

Hydrodynamic Performance of a Barge-Type Floating Offshore Wind Turbine with Moonpool

  • CHEN Yiren, YAO Jinyu, LI Mingxuan, ZHANG Xinshu

DOI
https://doi.org/10.16183/j.cnki.jsjtu.2022.521
Journal volume & issue
Vol. 58, no. 7
pp. 965 – 982

Abstract

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The hydrodynamic performance of a barge-type floating offshore wind turbine (FOWT) with a moonpool is studied in frequency domain with reference to the Ideol-Floatgen design. The correction of the viscous damping of the moonpool is considered. First, the resonance modes of the moonpool are analyzed. Then, the hydrodynamic coefficients of the FOWT under regular waves and the motion responses under irregular waves are investigated. Finally, the safety of the FOWT is verified with respect to the DNV standards. The results show that the dynamic pitch and nacelle acceleration of the barge-type FOWT meet the safety requirements under both operating and survival conditions. The investigation of the coupling effects of the platform motion and the moonpool resonance shows that the motion of the platform will cause the shift of the piston mode frequency of the moonpool and the reduction of the piston mode response amplitude, the frequency of the sloshing mode is basically unaffected, but the response amplitude of the first-order sloshing mode is increased. The motion responses of the barge-type FOWT with and without the moonpool are compared. It is found that the moonpool can reduce the motion response of the FOWT, and improve the overall hydrodynamic performance of the FOWT. The platform length, moonpool length and platform draught are parametrically analyzed. Surge, heave, pitch response RMS values and the nacelle acceleration response RMS value are used as the indicators of comparison. It is found that the increase of the platform length could effectively reduce the four response RMS values of the FOWT under both operating and survival conditions, the increase of the moonpool length will reduce the four response RMS values of the FOWT under the operating condition, and the increase of the platform draught could significantly reduce the four response RMS values of the FOWT under the survival condition, the heave and pitch response RMS values increase with the augmentation of the draught under the operating condition.

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