Modeling and Verification of Lumped-Parameter, Multibody Structural Dynamics for Offshore Wind Turbines

Rahman, Saad [University of Central Florida]; Sarker, Doyal [University of Central Florida]; Ngo, Tri [University of Central Florida]; Bergua, Roger [National Laboratory of the Rockies, Golden, CO (United States)] (ORCID:0000000347034729); Zalkind, Daniel [National Laboratory of the Rockies, Golden, CO (United States)]; Jonkman, Jason [National Laboratory of the Rockies, Golden, CO (United States)] (ORCID:0000000329907362); Das, Tuhin [University of Central Florida]

doi:10.1016/j.ifacol.2025.12.242

DOE OSTI · 3018002

Modeling and Verification of Lumped-Parameter, Multibody Structural Dynamics for Offshore Wind Turbines

Rahman, Saad [University of Central Florida]·Sarker, Doyal [University of Central Florida]·Ngo, Tri [University of Central Florida]·Bergua, Roger [National Laboratory of the Rockies, Golden, CO (United States)] (ORCID:0000000347034729)·Zalkind, Daniel [National Laboratory of the Rockies, Golden, CO (United States)]·Jonkman, Jason [National Laboratory of the Rockies, Golden, CO (United States)] (ORCID:0000000329907362)·Das, Tuhin [University of Central Florida]

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Abstract

This paper presents the modeling and verification of multibody structural dynamics for offshore wind turbines. The flexible tower and support structure of a monopile-based offshore wind turbine are modeled using an acausal, lumped-parameter, multibody approach that incorporates structural flexibility, soil-structure interaction, and hydrodynamic models. Simulation results are benchmarked against alternative modeling approaches, demonstrating the model's ability to accurately capture both static and dynamic behaviors under various wind and wave conditions while maintaining computational efficiency. This work provides a valuable tool for analyzing key structural characteristics of wind turbines, including eigenfrequencies, mode shapes, damping, and internal forces.

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Rahman, Saad [University of Central Florida], Sarker, Doyal [University of Central Florida], Ngo, Tri [University of Central Florida], Bergua, Roger [National Laboratory of the Rockies, Golden, CO (United States)] (ORCID:0000000347034729), Zalkind, Daniel [National Laboratory of the Rockies, Golden, CO (United States)], Jonkman, Jason [National Laboratory of the Rockies, Golden, CO (United States)] (ORCID:0000000329907362), Das, Tuhin [University of Central Florida]. 2025-12-22. Modeling and Verification of Lumped-Parameter, Multibody Structural Dynamics for Offshore Wind Turbines. https://doi.org/10.1016/j.ifacol.2025.12.242

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