Numerical Investigation of Sloped Wall Tank with Bottom-Mounted Internal Object for Structural Vibration Control

Abstract

Utilizing the inherent capacity of energy dissipation, liquid tanks are nowadays being employed as tuned liquid dampers (TLDs) for controlling unwanted structural vibration. The effective liquid mass that participates in convective mode controls the tank’s overall dynamic response. The stagnant liquid mass, which does not participate in sloshing at the bottom corners of the conventional rectangular and cylindrical TLDs, increases the total liquid mass and has no role in the vibration control of the supporting structure. The hydrodynamic behavior of the sloped wall tank under resonance conditions is demonstrated under harmonic excitation over a range of frequencies close to the fundamental sloshing frequency of the tank. However, the present study focuses on the effect of the modified geometrical configuration due to the bottom-mounted object on the slosh displacement and hydrodynamic base shear. A 2D finite element model developed employing the potential flow theory is used for the present numerical investigation. Compared to a conventional flat-bottom tank, the sloped wall tank exhibits a considerable increase in hydrodynamic base shear near resonance excitation. The dynamic impulsive and the convective response components of the base shear force have been successfully estimated. Also, the effectiveness of the proposed sloped wall tank with bottom-mounted internal object is examined under EL-Centro EW earthquake motion.