Arwade, SanjayDeGroot, DonBalakrishnan, Krishnaveni2024-09-192024-09-192024-0510.7275/54785https://hdl.handle.net/20.500.14394/54785Renewable energy is crucial, and floating offshore wind energy has immense potential. However, the current exorbitant cost of the substructure of a floating offshore wind turbine (FOWT) poses a significant challenge to its development. Thus, this thesis proposed a groundbreaking concept: instead of individual anchors, FOWTs could share anchors to enhance substructure efficiency and reduce costs. The purpose of this study was to analyze the strength dynamics of multiline anchors with varying parameters, such as floater type, turbine capacity, different mooring types and environmental factors. The National Renewable Energy Laboratory (NREL) 5 MW reference turbine and the OC3 Hywind spar platform were utilized to simulate multiline anchor forces and compared with the OC4 semisubmersible. In the wave-dominant survival load case, the peak value of net multiline anchor force in a spar was only 13% of that in a semisubmersible, while in operational conditions, the spar’s maximum anchor tension was 29% of that in a semisubmersible. Thus, it is unequivocal that wave forces have less impact on the spar platform than the semisubmersible platform. The multiline anchor was studied through numerical simulations using the layout geometry of an existing wind farm with two types of offshore platforms to compare multiline anchor forces. It was discovered that the maximum three-line anchor force in the case of a semisubmersible was 70% of the single-line force, while it was 50% in the case of a spar for a 0° Wind Wave Current (WWC) load condition. The directionality also revealed that the anchor forces in the case of a semisubmersible were more sensitive to wave forces than wind/current, while also more stable and undisturbed in the spar case. Multiline anchor forces were studied for two scenarios, with and without wake effects, using Jensen’s wake model. Reduced thrust forces due to wake caused lesser individual anchor forces and, therefore, lesser net multiline anchor forces. In cases where more turbines were in the downstream condition experiencing wake effects, the percentage of reduction in the multiline anchor force was higher. In contrast, if the downstream turbines were spaced farther apart, the percentage of reduction in the multiline force was almost negligible. Collective parametric studies were conducted in a taut mooring system for deeper water. It was discovered that the multiline anchor force increased with an increase in taut angle and water depth. An increase in turbine capacity by a factor of three caused the multiline anchor force to increase by a factor of 1.5. The 60 wind-wave-current direction caused the peak multiline anchor force as many mooring lines connected to the multiline anchor were under a similar and higher state of tension in WWC direction.Attribution 4.0 Internationalhttp://creativecommons.org/licenses/by/4.0/Floating wind, Offshore wind, Turbines, Multiline Anchors, Mooring systemDissertation (Open Access)https://orcid.org/0000-0003-4285-9721