VORTEX INDUCED VIBRATION CONTROL OF WIND TURBINE TOWERS USING TUNED MASS DAMPER INERTER

With the rapid global expansion of wind energy and the increasing installed capacity, wind turbines are being constructed taller and more slender to maximize energy capture. However, this structural trend makes them more vulnerable to vortex-induced vibrations (VIV), posing significant challenges to stability, durability, and long-term reliability. This study explores VIV control in wind turbine towers using a tuned mass damper inerter (TMDI). A fluid-structure interaction model is developed based on the energy method, incorporating vortex shedding dynamics represented by the van der Pol nonlinear equation. The model is validated using the NREL 5 MW baseline wind turbine and applied to study VIV suppression using both a traditional tuned mass damper (TMD) with optimal tuning parameters and a TMDI. The results show that an optimally tuned TMD can reduce displacement amplitude by 60% within the lock-in frequency range, even with a small TMD-to-Tower mass ratio of 0.2%. The addition of an inerter further enhances vibration suppression within the wind speed range of 6.9-7.2 m/s, with larger inerter mass ratios yielding better performance. However, outside this range, the TMDI introduces additional displacement peaks, reducing overall control effectiveness compared to the traditional TMD. Notably, the inerter also significantly reduces the dynamic displacement of the TMD itself, offering a practical advantage for installations where space constraints limit allowable TMD motion. These findings offer valuable insights into the design trade-offs of TMDI systems for effective VIV mitigation in wind turbine towers.