Investigation of nonlinear difference-frequency wave excitation on a semisubmersible offshore-wind platform with bichromatic-wave CFD simulations

Lu Wang, Amy Robertson, Jason Jonkman, Yi-Hsiang Yu, Arjen Koop, Adrià Borràs Nadal, Haoran Li, Wei Shi, Romain Pinguet, Yang Zhou, Qing Xiao, Rupesh Kumar, Hamid Sarlak

研究成果: Conference contribution同行評審

11 引文 斯高帕斯(Scopus)

摘要

The natural surge and pitch frequencies of semisubmersible offshore wind platforms are typically designed to be below the wave frequencies to avoid direct excitation. However, surge or pitch resonance can be excited by the nonlinear low-frequency loads generated by irregular incident waves. Second-order potential-flow models with added Morison drag have been found to underpredict this low-frequency excitation and response. As part of the OC6 project1, the authors performed computational fluid dynamics (CFD) simulations to enable a better understanding of the low-frequency loads and the limitations of lower-fidelity models. The focus of this paper is to set up a computationally cost-effective CFD simulation of a fixed semisubmersible platform to investigate nonlinear differencefrequency loads and establish the corresponding uncertainty in the results. Because of the high computing cost, CFD simulations of irregular waves can be challenging. Instead, simulations were performed with bichromatic waves having a shorter repeat period. A preliminary comparison with quadratic transfer functions from second-order potential-flow theory shows that CFD models consistently predict higher nonlinear wave loads at the difference frequency, likely because of flow separation and viscous drag not accounted for in potential-flow theory.

原文English
主出版物標題Proceedings of the ASME 2021 3rd International Offshore Wind Technical Conference, IOWTC 2021
發行者American Society of Mechanical Engineers (ASME)
章節V001T01A009
頁數14
ISBN(電子)9780791884768
DOIs
出版狀態Published - 16 4月 2021
事件ASME 2021 3rd International Offshore Wind Technical Conference, IOWTC 2021 - Virtual, Online
持續時間: 16 2月 202117 2月 2021

出版系列

名字Proceedings of the ASME 2021 3rd International Offshore Wind Technical Conference, IOWTC 2021

Conference

ConferenceASME 2021 3rd International Offshore Wind Technical Conference, IOWTC 2021
城市Virtual, Online
期間16/02/2117/02/21

指紋

深入研究「Investigation of nonlinear difference-frequency wave excitation on a semisubmersible offshore-wind platform with bichromatic-wave CFD simulations」主題。共同形成了獨特的指紋。

引用此