Revisiting equivalent tuned mass damper analogy for tuned liquid damper utilizing CFD-FEA framework

Abstract

The equivalent mechanical model (EMM) of a tuned liquid damper (TLD) is represented through an analogous spring-mass-dashpot system that resembles a tuned mass damper. The present work utilizes the computational fluid dynamics-finite element analyses (CFD-FEA) framework to study the structure-TLD coupled dynamics. A single-storey single-bay building with TLD is taken. The performance of the TLD and the liquid free-surface profile for different structural damping ratios and excitation amplitudes are determined from CFD-FEA. The efficiency of the TLD, obtained from the CFD-FEA and EMM are compared for harmonic and seismic excitations and different TLD configurations. The results indicate that for low excitation amplitude and high structural damping, EMM may be adopted to predict TLD performance. EMM indicates gradual deterioration in the TLD performance as the depth ratio increases, whereas CFD-FEA shows an optimum TLD performance for a depth ratio equal to 0.15. Under seismic excitations, both EMM and CFD-FEA highlight the effectiveness of the TLD, though there is variation in the damper efficacy for individual earthquakes obtained using the two methods. It is also observed that the performance of the TLD along a particular direction does not alter under the bidirectional loading scenario. In case of bidirectional loading, the liquid free-surface displacement is more though it does not enhance the damper performance.