Abstract
Model-scale testing of floating wind turbine substructures is an integral part of design verification. Yet, both the test-facility and Froude-scales used, raise questions over the suitability of the hydrodynamic coefficients obtained. In this study, experimental measurements from towing tank tests with a 1:100 scale model of the INO WINDMOOR semi-submersible are directly compared to those from ocean basin tests of a 1:40 scale model. Dry inertial parameters for the two physical models are maintained within approximately 10% and very similar motion responses were found in the wave- and low-frequency ranges for the main degrees-of-freedom in a variety of irregular wave cases. Some significant discrepancies on mooring loads were obtained in the low-frequency range, thought to be due to differences in low-frequency incident energy.