Smoothed Particle Hydrodynamics (SPH)

Abstract

The roll motion response of a single degree of freedom (SDOF) structural system to which a rigid rectangular partially filled liquid tank has been attached is considered. The SDOF structural system with the empty tank is first described with a mathematical model and this model is validated by performing decay experiments as well as experiments in which periodic excitations are applied to the system. The responses are accurately predicted by the model. The accuracy of these predictions allows us to study both experimentally and numerically, with weakly compressible SPH, the performance of the partially filled tank as a tuned liquid damper (TLD). The sloshing flows inside the tank comprise the onset of breaking waves which make the TLDs devices extremely difficult to model, especially for the potential flow multimodal approaches commonly used to simulate these sorts of coupled systems. In order to characterise the wave breaking effects on the response curves, tests have been performed with liquids of different viscosity, the increasing viscosity preventing the onset of breaking waves. The capabilities of SPH to treat this coupling problem are assessed and the results show that SPH is able to capture a substantial part of the physics involved in the addressed phenomena but further work remains still to be done relating to a more accurate treatment of the laminar viscosity and turbulence effects.