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The purpose of this dataset is to provide filtered, averaged buoy surface meteorological and oceanographic data and standardize the data format into NetCDF. The buoy was deployed by NDBC. These data are part of the observational database created for supporting the floating offshore wind project within the DOE-funded ORACLE project.
The purpose of this dataset is to provide filtered, averaged buoy surface meteorological and oceanographic data and standardize the data format into NetCDF. The buoy was deployed by NDBC. These data are part of the observational database created for supporting the floating offshore wind project within the DOE-funded ORACLE project.
The purpose of this dataset is to provide filtered, averaged buoy surface meteorological and oceanographic data and standardize the data format into NetCDF. The buoy was deployed by NDBC. These data are a part of the observational database created for supporting the floating offshore wind project within the DOE-funded ORACLE project.
The purpose of this dataset is to provide filtered, averaged buoy surface meteorological and oceanographic data and standardize the data format into NetCDF. The buoy was deployed by NDBC. These data are part of the observational database created for supporting the floating offshore wind project within the DOE-funded ORACLE project.
The purpose of this dataset is to provide filtered, averaged buoy surface meteorological and oceanographic data and standardize the data format into NetCDF. The buoy was deployed by NDBC. These data are part of the observational database created for supporting the floating offshore wind project within the DOE-funded ORACLE project.
The purpose of this dataset is to provide filtered, averaged buoy surface meteorological and oceanographic data and standardize the data format into NetCDF. The buoy was deployed by NDBC. These data are part of the observational database created for supporting the floating offshore wind project within the DOE-funded ORACLE project.
The purpose of this dataset is to provide filtered, averaged buoy surface meteorological and oceanographic data and standardize the data format into NetCDF. The buoy was deployed by NDBC. These data are part of the observational database created for supporting the floating offshore wind project within the DOE-funded ORACLE project.
The purpose of this dataset is to provide filtered, averaged buoy surface meteorological and oceanographic data and standardize the data format into NetCDF. The buoy was deployed by NDBC. These data are part of the observational database created for supporting the floating offshore wind project within the DOE-funded ORACLE project.
The purpose of this dataset is to provide filtered, averaged buoy surface meteorological and oceanographic data and standardize the data format into NetCDF. The buoy was deployed by NDBC. These data are part of the observational database created for supporting the floating offshore wind project within the DOE-funded ORACLE project.
The purpose of this dataset is to provide filtered, averaged buoy surface meteorological and oceanographic data and standardize the data format into NetCDF. The buoy was deployed by NDBC. These data are part of the observational database created for supporting the floating offshore wind project within the DOE-funded ORACLE project.
The purpose of this dataset is to provide filtered, averaged buoy surface meteorological and oceanographic data and standardize the data format into NetCDF. The buoy was deployed by NDBC. These data are part of the observational database created for supporting the floating offshore wind project within the DOE-funded ORACLE project.
The purpose of this dataset is to provide filtered, averaged buoy surface meteorological and oceanographic data and standardize the data format into NetCDF. The buoy was deployed by NDBC. These data are part of the observational database created for supporting the floating offshore wind project within the DOE-funded ORACLE project.
The purpose of this dataset is to provide filtered, averaged buoy surface meteorological and oceanographic data and standardize the data format into NetCDF. The buoy was deployed by NDBC. These data are part of the observational database created for supporting the floating offshore wind project within the DOE-funded ORACLE project.
The purpose of this dataset is to provide filtered, averaged buoy surface meteorological and oceanographic data and standardize the data format into NetCDF. The buoy was deployed by NDBC. These data are part of the observational database created for supporting the floating offshore wind project within the DOE-funded ORACLE project.
High frequency (HF) radar systems measure the speed and direction of ocean surface currents in near real time provided by Integrated Ocean Observing System (IOOS). The HFR data along the Pacific Coast are at a spatial resolution of 2 km. These data are collected as part of an observational database developed to support the floating offshore wind energy research within the ORACLE project funded by DOE WETO.
High frequency (HF) radar systems measure the speed and direction of ocean surface currents in near real time provided by Integrated Ocean Observing System (IOOS). The HFR data along the Pacific Coast are at a spatial resolution of 6 km. These data are collected as part of an observational database developed to support the floating offshore wind energy research within the ORACLE project funded by DOE WETO.
Currently, the design of floating offshore wind systems is primarily based on mid-fidelity models with empirical drag forces. The tuning of the model coefficients requires data from either experiments or high-fidelity simulations. As part of the OC6 (Offshore Code Comparison Collaboration, Continued, with Correlation, and unCertainty (OC6) is a project under the International Energy Agency Wind Task 30 framework) project, the present investigation explores the latter option. A verification and validation study of computational fluid dynamics (CFD) models of the DeepCwind semisubmersible undergoing free-decay motion is performed. Several institutions provided CFD results for validation against the OC6 experimental campaign. The objective is to evaluate whether the CFD setups of the participants can provide valid estimates of the hydrodynamic damping coefficients needed by mid-fidelity models. The linear and quadratic damping coefficients and the equivalent damping ratio are chosen as metrics for validation. Large numerical uncertainties are estimated for the linear and quadratic damping coefficients; however, the equivalent damping ratios are more consistently predicted with lower uncertainty. Some difference is observed between the experimental and CFD surge-decay motion, which is caused by mechanical damping not considered in the simulations that likely originated from the mooring setup, including a Coulomb-friction-type force. Overall, the simulations and the experiment show reasonable agreement, thus demonstrating the feasibility of using CFD simulations to tune mid-fidelity models.
Current mid-fidelity modeling approaches for floating offshore wind turbines (FOWTs) have been found to underpredict the nonlinear, low-frequency wave excitation and the response of semisubmersible FOWTs. To examine the cause of this underprediction, the OC6 project is using computational fluid dynamics (CFD) tools to investigate the wave loads on the OC5-DeepCwind semisubmersible, with a focus on the nonlinear difference-frequency excitation. This paper focuses on assessing the uncertainty of the CFD predictions from simulations of the semisubmersible in a fixed condition under bichromatic wave loading and on establishing confidence in the results for use in improving mid-fidelity models. The uncertainty for the nonlinear wave excitation is found to be acceptable but larger than that for the wave-frequency excitation, with the spatial discretization error being the dominant contributor. Further, unwanted free waves at the difference frequency have been identified in the CFD solution. A wave-splitting and wave load-correction procedure are presented to remove the contamination from the free waves in the results. A preliminary comparison to second-order potential-flow theory shows that the CFD model predicted significantly higher difference-frequency wave excitations, especially in surge, suggesting that the CFD results can be used to better calibrate the mid-fidelity tools.