On the characteristics of fluid flow field and oscillatory response of tuned liquid multi-column dampers

The tuned liquid column damper (TLCD) operates as a fluid counterpart to a tuned mass damper (TMD), harnessing the dynamics of liquid flow to effectively counteract unwanted vibrations, thereby achieving the stability within the structural system. Most recently, to overcome the shortcoming that conventional TLCDs can only control the vibration of structures in a single direction, a toroidal tuned liquid multi-column damper (TLMCD) was proposed and its control effectiveness was preliminarily validated. However, the hydrodynamic characteristics of the TLMCD remain elusive and warrant further clarification. Therefore, this study employs computational fluid dynamics (CFD) methodology to meticulously simulate the intricate threedimensional multiphase flow dynamics within toroidal TLMCDs across a spectrum of excitation conditions, aiming to elucidate their hydrodynamic behaviors. The efficacy of the CFD-based simulation approach is validated through a comparative analysis of numerically computed and experimentally measured liquid displacement responses. The error magnitude of the simplified theoretical model for toroidal TLMCDs is assessed by comparing the outcomes derived from CFD simulations with the theoretical predictions. Furthermore, by visualizing the spatial and temporal distribution of fluid flow field, the three-dimensional fluid flow properties of toroidal TLMCDs are characterized. The findings presented highlight the frequency-dependent nonlinear characteristics of liquid column oscillatory responses, providing a valuable benchmark for the development of more refined theoretical models and guiding the optimization of fluid-type dampers.