Comparative study of transient and quasi-steady aeroelastic analysis of composite wind turbine blade in steady wind conditions

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2014
Sargın, Hakan
The objective of this study is to conduct a comparative study of the transient and quasi-steady aeroelastic analysis of a composite wind turbine blade in steady wind conditions. Transient analysis of the wind turbine blade is performed by the multi-body dynamic code Samcef Wind Turbine which uses blade element momentum theory for aerodynamic load calculation. For this purpose, a multi-body wind turbine model is generated with rigid components except for the turbine blades. For the purposes of the study, a reference three dimensional blade is designed using inverse design methodology. Dynamic superelement of the turbine blades are created and introduced into multi-body model of the wind turbine system, and transient aeroelastic analysis of the multi-body wind turbine system is performed in steady wind conditions. As a follow-up study, quasi-steady aeroelastic analysis of the same composite wind turbine blade is performed by coupling a structural finite element solver with an aerodynamic tool based on blade element momentum theory. Quasi-steady aeroelastic analysis of the blade is performed at different azimuthal positions of the blade and transient effects due to the rotation of the blade are ignored. The article aims at investigating the applicability of quasi-steady aeroelastic modeling of the turbine blade in steady wind conditions by comparing the deformations obtained by quasi-steady aeroelastic analysis and transient aeroelastic analysis of the complete turbine system at the same azimuthal positions of the blade. The presented results conclude that the quasi-steady aeroelastic analysis and transient aeroelastic analysis have a close match and the coupling between the finite element solver with a blade element momentum based aerodynamic tool can be used for static aeroelastic analysis at preliminary design state of a composite wind turbine blade.

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Citation Formats
H. Sargın, “Comparative study of transient and quasi-steady aeroelastic analysis of composite wind turbine blade in steady wind conditions,” M.S. - Master of Science, Middle East Technical University, 2014.