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OC7 phase I: Toward practical sea-state-dependent modeling of hydrodynamic viscous drag and damping

Wang, Lu [National Renewable Energy Laboratory (NREL), Golden, CO (United States)] (ORCID:0000000167398998)·Robertson, Amy [National Renewable Energy Laboratory (NREL), Golden, CO (United States)] (ORCID:0000000174484632)·Jonkman, Jason [National Renewable Energy Laboratory (NREL), Golden, CO (United States)] (ORCID:0000000329907362)·Liao, Yingqian [National Renewable Energy Laboratory (NREL), Golden, CO (United States)]·Berthelsen, Petter Andreas [SINTEF Ocean AS, Trondheim (Norway)] (ORCID:000900054867448X)·Abdelmoteleb, Serag-Eldin [SINTEF Ocean AS, Trondheim (Norway)] (ORCID:0000000155995533)·Rohrer, Peter [Norwegian Univ. of Science and Technology, Trondheim (Norway)] (ORCID:0000000281239974)·Ramachandran Nair Rajasree, Vishnu [Norwegian Univ. of Science and Technology, Trondheim (Norway)] (ORCID:0009000218671745)·Bachynski-Polić, Erin [Norwegian Univ. of Science and Technology, Trondheim (Norway)] (ORCID:0000000214718254)·Clement, Constance [PRINCIPIA, La Ciotat (France)]·Le Cunff, Cédric [PRINCIPIA, La Ciotat (France)]·Vlachogiannis, Prokopios [Électricité de France, Chatou (France)] (ORCID:000900097002428X)·Peyrard, Christophe [Électricité de France, Chatou (France)]·Pham, Dam Thanh [Univ. College Cork (Ireland)] (ORCID:0000000238532059)·Leahy, Paul [Univ. College Cork (Ireland)] (ORCID:0000000344783863)·Bouysses, Valérie [Bureau Veritas, Saint-Herblain (France)]·Brun, Cédric [Bureau Veritas, Saint-Herblain (France)]·Wang, Lizhong [Zhejiang Univ., Hangzhou (China)]·Wang, Lilin [Zhejiang Univ., Hangzhou (China)]·Teng, Long [Zhejiang Univ., Hangzhou (China)]·Shi, Wei [Dalian Univ. of Technology (China)] (ORCID:0000000263120494)·Fu, Yushun [Dalian Univ. of Technology (China)]·Abid, Ali [Dalian Univ. of Technology (China)]·Cheng, Zhengshun [Shanghai Jiao Tong Univ. (China)]·Chen, Peng [Shanghai Jiao Tong Univ. (China)] (ORCID:0009000100356133)·Hu, Zhirong [Shanghai Jiao Tong Univ. (China)]·Bai, Haozhe [Norwegian Univ. of Science and Technology, Trondheim (Norway); Ocean Univ. of China (China)] (ORCID:0009000747151569)·Xu, Kun [Ocean Univ. of China (China)]·Das, Tuhin [Univ. of Central Florida, Orlando, FL (United States)] (ORCID:0009000850992366)·Sarker, Doyal [Univ. of Central Florida, Orlando, FL (United States)] (ORCID:0009000610999251)·Ngo, Tri [Univ. of Central Florida, Orlando, FL (United States)] (ORCID:0000000267487170)·Trubat Casal, Pau [Univ. Politecnica de Catalunya (Spain)] (ORCID:0000000182928272)·Molins, Climent [Univ. Politecnica de Catalunya (Spain)] (ORCID:0000000182920473)·Niosi, Francesco [Polytechnic Univ. of Turin (Italy)] (ORCID:0000000251053482)·Dell'Edera, Oronzo [Polytechnic Univ. of Turin (Italy)] (ORCID:0000000276524324)·Paduano, Bruno [Polytechnic Univ. of Turin (Italy)] (ORCID:0000000205989853)·Bertozzi, Andrea [Polytechnic Univ. of Turin (Italy)] (ORCID:0009000512141737)·Bracco, Giovanni [Polytechnic Univ. of Turin (Italy)] (ORCID:000000024793202X)·Tagliafierro, Bonaventura [Univ. of Salerno (Italy); Uppsala Univ. (Sweden)]·Moghtadaei, Abdolmajid [Gavin & Doherty Geosolutions Ltd., Dublin (Ireland)]·Wright, Christopher [Gavin & Doherty Geosolutions Ltd., Dublin (Ireland)] (ORCID:0000000312961477)
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Abstract

Here, this article presents a collaborative research campaign under the OC7 project on refining the engineering modeling approach for hydrodynamic viscous drag and damping on floating wind platforms, focusing on the adjustment of hydrodynamic drag and damping coefficients for different sea states. The participant simulation results show significant improvements over the previous OC6 project in predicting the low-frequency resonance motion under nonoperational conditions. The improvements are mainly due to enhanced modeling, including the adoption of wave stretching, and directly tuning the coefficients to measured platform motion in waves instead of free decay. For accurate predictions of mean- and slow-drift motion, the better performing models use a decreasing column splash zone drag coefficient and increasing surge damping/drag with increasing wave height. The model tuning for heave and pitch resonance shows less consistency. Generally, both quadratic drag and additional heave or pitch damping are needed for accurate predictions. Alternatively, a quadratic drag formulation with velocity filtering for the rectangular pontoons leads to improved predictions without additional damping. This model is also potentially more predictive, requiring minimal adjustment to its parameters for different conditions.

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17 WIND ENERGYOC7WINDMOORdraghydrodynamicslow frequencyresonancesea statevalidationviscous

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Wang, Lu [National Renewable Energy Laboratory (NREL), Golden, CO (United States)] (ORCID:0000000167398998), Robertson, Amy [National Renewable Energy Laboratory (NREL), Golden, CO (United States)] (ORCID:0000000174484632), Jonkman, Jason [National Renewable Energy Laboratory (NREL), Golden, CO (United States)] (ORCID:0000000329907362), Liao, Yingqian [National Renewable Energy Laboratory (NREL), Golden, CO (United States)], Berthelsen, Petter Andreas [SINTEF Ocean AS, Trondheim (Norway)] (ORCID:000900054867448X), Abdelmoteleb, Serag-Eldin [SINTEF Ocean AS, Trondheim (Norway)] (ORCID:0000000155995533), Rohrer, Peter [Norwegian Univ. of Science and Technology, Trondheim (Norway)] (ORCID:0000000281239974), Ramachandran Nair Rajasree, Vishnu [Norwegian Univ. of Science and Technology, Trondheim (Norway)] (ORCID:0009000218671745), Bachynski-Polić, Erin [Norwegian Univ. of Science and Technology, Trondheim (Norway)] (ORCID:0000000214718254), Clement, Constance [PRINCIPIA, La Ciotat (France)], Le Cunff, Cédric [PRINCIPIA, La Ciotat (France)], Vlachogiannis, Prokopios [Électricité de France, Chatou (France)] (ORCID:000900097002428X), Peyrard, Christophe [Électricité de France, Chatou (France)], Pham, Dam Thanh [Univ. College Cork (Ireland)] (ORCID:0000000238532059), Leahy, Paul [Univ. College Cork (Ireland)] (ORCID:0000000344783863), Bouysses, Valérie [Bureau Veritas, Saint-Herblain (France)], Brun, Cédric [Bureau Veritas, Saint-Herblain (France)], Wang, Lizhong [Zhejiang Univ., Hangzhou (China)], Wang, Lilin [Zhejiang Univ., Hangzhou (China)], Teng, Long [Zhejiang Univ., Hangzhou (China)], Shi, Wei [Dalian Univ. of Technology (China)] (ORCID:0000000263120494), Fu, Yushun [Dalian Univ. of Technology (China)], Abid, Ali [Dalian Univ. of Technology (China)], Cheng, Zhengshun [Shanghai Jiao Tong Univ. (China)], Chen, Peng [Shanghai Jiao Tong Univ. (China)] (ORCID:0009000100356133), Hu, Zhirong [Shanghai Jiao Tong Univ. (China)], Bai, Haozhe [Norwegian Univ. of Science and Technology, Trondheim (Norway); Ocean Univ. of China (China)] (ORCID:0009000747151569), Xu, Kun [Ocean Univ. of China (China)], Das, Tuhin [Univ. of Central Florida, Orlando, FL (United States)] (ORCID:0009000850992366), Sarker, Doyal [Univ. of Central Florida, Orlando, FL (United States)] (ORCID:0009000610999251), Ngo, Tri [Univ. of Central Florida, Orlando, FL (United States)] (ORCID:0000000267487170), Trubat Casal, Pau [Univ. Politecnica de Catalunya (Spain)] (ORCID:0000000182928272), Molins, Climent [Univ. Politecnica de Catalunya (Spain)] (ORCID:0000000182920473), Niosi, Francesco [Polytechnic Univ. of Turin (Italy)] (ORCID:0000000251053482), Dell'Edera, Oronzo [Polytechnic Univ. of Turin (Italy)] (ORCID:0000000276524324), Paduano, Bruno [Polytechnic Univ. of Turin (Italy)] (ORCID:0000000205989853), Bertozzi, Andrea [Polytechnic Univ. of Turin (Italy)] (ORCID:0009000512141737), Bracco, Giovanni [Polytechnic Univ. of Turin (Italy)] (ORCID:000000024793202X), Tagliafierro, Bonaventura [Univ. of Salerno (Italy); Uppsala Univ. (Sweden)], Moghtadaei, Abdolmajid [Gavin & Doherty Geosolutions Ltd., Dublin (Ireland)], Wright, Christopher [Gavin & Doherty Geosolutions Ltd., Dublin (Ireland)] (ORCID:0000000312961477). 2025-06-11. OC7 phase I: Toward practical sea-state-dependent modeling of hydrodynamic viscous drag and damping. https://doi.org/10.1016/j.oceaneng.2025.121745

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