Cross-comparison analysis of environmental load components in extreme conditions for pontoon-connected semi-submersible FOWT using CFD and potential-based tools

• Published in: Ocean engineering 2024-07, Vol.304, p.117248, Article 117248
• Main Authors: Yang, Ho-Seong, Alkhabbaz, Ali, Tongphong, Watchara, Lee, Young-Ho
• Format: Article
• Language: English
• Subjects: 10 MW-Turbine; Computational fluid dynamics (CFD); Floating offshore wind turbine (FOWT); Hydrodynamic coefficient; Middle -fidelity simulation tool; Pontoon
• ISSN: 0029-8018; 1873-5258
• DOI: 10.1016/j.oceaneng.2024.117248

This study focuses on analyzing the load response prediction error of a potential-based tool for a Floating Offshore Wind Turbine (FOWT) with a rectangular pontoon connected to the lower part of the column. The system response was reviewed under extreme environmental loads, and CFD analysis results were compared to analyze the response prediction error contributed by each load component. Based on the CFD free-decay simulation results, we performed potential-based tool calibration by applying damping coefficient and Morison drag coefficient in a composite manner. Through coefficient calibration, the response in the free-decay analysis matched well with the CFD, but there was a significant difference from CFD in the integrated load analysis. Through this study, it was clearly shown that applying an appropriate drag coefficient is very important to implement drag force, especially wave drag force, for FOWT where columns are connected by pontoons. It was confirmed that initial calibration of the potential-based tool using only free-decay analysis is not an appropriate method. However, by applying damping coefficient and Morison drag coefficient in a composite manner when calibrating the potential-based tool based on the free-decay analysis results, it was possible to improve the error by reflecting the current load, and it is expected that the error in the response prediction of the potential-based tool can be further improved through appropriate composite application. •Identifying significant discrepancies in integrated load analysis between CFD and potential-based tools.•Key to FOWT accuracy: applying correct drag coefficients for wave forces."Highlighting the limitations of calibrating potential-based tools solely with free-decay analysis results.A method combining damping and Morison coefficients enhances FOWT tool accuracy.•Highlighting the limitations of calibrating potential-based tools solely with free-decay analysis results.•A method combining damping and Morison coefficients enhances FOWT tool accuracy.