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In this paper, the problem of wind-induced vibration in tall buildings is addressed by utilizing a new type of damper, the tuned mass damper fluid inerter (TMDFI). The TMDFI incorporates an inerter in the classical tuned mass damper (TMD), which is physically realized using fluid in a helical channel. The device arrangement is optimized using a proposed nonlinear procedure and it is demonstrated through numerical simulations that the application of the TMDFI achieves excellent vibration control performance. Specifically, it has been found that the TMDFI requires lower mass and stroke requirements than traditional passive dampers while achieving comparable or better vibration reductions. It has been shown numerically that the damper demonstrates excellent vibration control capabilities by reducing the RMS displacement of the building by ≈50% and the RMS acceleration by 35%–80%. The results presented here show that the TMDFI is a damper capable of mitigating wind-induced vibrations in tall buildings with relatively simple design requirements. This new damper has the potential to significantly improve the safety, comfort, and durability of tall buildings subjected to wind loads. [ABSTRACT FROM AUTHOR]

This paper proposes the use of a tuned mass damper fluid-inerter (TMDFI) for vibration control of spar-type floating offshore wind turbine towers. The use of an inerter in parallel with the spring and damper of a tuned mass damper (TMD) is a relatively new concept. The ideal inerter has a mass amplification effect on the classical TMD leading to greater vibration control capabilities. Previous work by the authors has shown that inerter based TMDs have great potential in vibration control of floating offshore wind turbines where enhanced vibration mitigation can be achieved using a relatively lighter device than classical TMDs. However, this previous work was based on the assumption of an ideal inerter that assumes the use of a mechanical flywheel type inerter. Mechanical inerters have some inherent disadvantages due to their complexity in design and high cost of maintenance. The use of a fluid inerter can alleviate these disadvantages as its design is rather simple and it comes with very low maintenance. Such devices have been proposed and investigated in the literature, however, their applicability in vibration control of floating wind turbines has not been investigated by researchers. The optimal design of a TMDFI is presented in this paper. It has been shown that optimization of a TMDFI is a six-dimensional non-linear optimization problem whose solution hyperplane contains multiple local minima. A systematic way has been developed in this paper, avoiding the use of metaheuristic search techniques, to optimize the damper while providing greater insight into the damper properties that offers a set of guidance to the designer. Numerical results demonstrate impressive vibration control capabilities of this new device under various stochastic wind-wave loads. It has been shown that the fluid-inerter performs as well as the ideal mechanical inerter. The considerable advantages of a TMDFI over the classical TMD demonstrated in this paper makes it an exciting candidate for vibration control. • Proposed tuned mass-damper-fluid-inerter (TMDFI) for FOWT tower vibration control. • Developed approach of finding global minima of a 6D TMDFI optimization problem. • Provides insight into the properties and behaviour of the TMDFI for designers. • TMDFIs impressively control FOWT tower vibrations significantly better than TMDs. [ABSTRACT FROM AUTHOR]