Date of Award

Spring 5-10-2019

Level of Access Assigned by Author

Open-Access Thesis

Degree Name

Master of Science in Mechanical Engineering (MSME)


Mechanical Engineering


Andrew Goupee

Second Committee Member

Habib Dagher

Third Committee Member

Anthony Viselli

Additional Committee Members

Masoud Rais-Rohani


Floating offshore wind turbine (FOWT) hull technologies are evolving rapidly with many technically viable designs. However, a commercially dominant architecture has yet to emerge. This thesis presents a methodology for evaluation of the hydrodynamic performance of an annular FOWT hull. This hull shows significant promise from a manufacturing and installation standpoint, but limited performance data exists. This thesis will provide ample documentation on scale model testing of an annular FOWT hull as well as the corresponding numerical validation approach and opportunities for design improvement.

The first portion of this work involves testing a 1/100th-scale model in the Harold Alfond Wind Wave Ocean Engineering Laboratory at the University of Maine’s Advanced Structures and Composites Center followed by an investigation of wave-induced motion using ANSYS AQWA, a commercial hydrodynamic software. The experimental and numerical results are compared to determine the ability of ANSYS AQWA to simulate the response of an annular FOWT hull, which here implies that the hull contains a moonpool. The wave-only performance of the annular hull is also compared to experimental data obtained for other baseline FOWT hulls. In addition to quantifying a baseline hull, this thesis will also explore modifications in the annular geometry to further explore the design space in an effort to find a more optimal annular hull configuration for use in FOWT applications.