Parameter optimization and vibration reduction effect of one C-shaped particle damping-tuned mass damper for offshore wind turbine

In recent years, offshore wind power has experienced rapid growth, with a notable trend toward installing wind turbines in more profound and more remote seas, accompanied by an increase in the size of offshore wind turbine (OWT). Consequently, the OWT structures are facing increasingly severe environmental loads, giving rise to challenges such as excessive vibrations and long-term fatigue. Since the spatial limit of the wind turbine and tower prevents the installation of too large or heavy dampers and also avoids excessive damper displacements, there currently needs to be more vibration-damping devices that can be practically used in OWT. To address the above problems, a new C-shaped particle damping-tuned mass damper (C-shaped PD-TMD) for offshore wind turbine tower space was innovatively proposed in this research, and the damper plasmonic arrangement and plasmonic bin form were both investigated based on the finite-element and discrete-element coupled (FEM-DEM) numerical model of OWT. Subsequently, a two-particle simplified theoretical model was used to transform the nonlinear structure into a linear one, solving the problem of highly correlated PD-TMD parameters and verifying the accuracy of the model. Then, the optimal parameters of the PD-TMD are obtained by the particle swarm optimization method based on this simplified theoretical model. The vibration reduction effects of PD-TMD and TMD were compared using the simplified wind turbine model and the overall OWT model. It is found that PD-TMD shows superior damping performance in the case of large structural displacements. Under simple harmonic and stochastic loads excitation, PD-TMD exhibits a better vibration effect on the structure, with a wider damping frequency band and stronger robustness. The PD-TMD shows better vibration suppression performance than the TMD under the excitation of multiple conditions, and the PD-TMD can reduce the peak relative displacement between the main structure and the damper by a maximum of 12.44%.