Prediction of energy dissipation in violent sloshing flows simulated by Smoothed Particle Hydrodynamics

The present work aims to investigate the use of fuel sloshing to reduce the design loads on aircraft wings. These are highly flexible structures, that can deform significantly under certain loading. Wings house the fuel tanks, and generally carry an amount of fuel comparable in weight to that of their structural components. In the present research the SPH model is adopted to investigate the damping effect of fuel sloshing on the dynamics of flexible wing-like structures. This represents a quite challenging task for SPH and more in general, for CFD tools, being the fuel tank under study subjected to vertical accelerations as high as 10g. The resulting flow is extremely complex due to the highly turbulent flow, the violent impacts and intense fragmentation of the air-liquid interface. The straightforward application of SPH to the problem suffers from some numerical issues, such as the tensile instability. To this aim the recent ?-LES-SPH model is adopted. The focus of the analysis is on the energy balance of the mechanical system. In particular, the experiments in [14] are reproduced in the numerical simulations comparing the flow evolution and the obtained forces and dissipated energy.