CFD Simulation of a Floating Offshore Wind Turbine System Using a Quasi-Static Crowfoot Mooring-Line Model

A general quasi-static crowfoot mooring-line model is developed and applied to the 5MW floating offshore wind turbine (FOWT) conceptualized by the National Renewable Energy Laboratory (NREL) in the Offshore Code Comparison Collaboration (OC3). This model is implemented into the CFD solver, CFDShip-Iowa V4.5. The model is first validated against experimental data for free-decay tests. A full-system simulation with wave and wind excitation is performed by utilizing the crowfoot model. The present study predicts less overall platform motion. Predicted power is shown to rely heavily on system pitching and surging motions. The system simulation shows that the crowfoot model eliminates the need for a geometric line approximation.

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