Ricerc@Sapienza

Liquid metals offer unique properties and their use in a nuclear fusion reactor, both as confined flows and free surface flow, is widely studied in the fusion community. The interaction between this conductive fluid and the tokamak magnetic fields leads to Magnetohydrodynamic (MHD) phenomena that influence the flow features. To properly design components that employ liquid metals, it is necessary to accurately predict these features and, although the efforts made in development, a mature code specifically customized to simulate MHD flows is still unavailable.

We propose a three-dimensional numerical model for non-hydrostatic free surface flows in which the Navier-Stokes equations are expressed in integral form on a coordinate system in which the vertical coordinate is varying in time. By a time-dependent coordinate transformation, the irregular time varying physical domain is transformed into a uniform fixed computational domain, in which the equations of motion are numerically integrated by a shock-capturing scheme based on WENO reconstruction and an approximate HLL Riemann Solver.

Submerged shore-parallel breakwaters for coastal defence are a good compromise between the need to mitigate the effects of waves on the coast and the ambition to ensure the preservation of the landscape and water quality. In this work we simulate, in a fully three-dimensional form, the hydrodynamic effects induced by submerged breakwaters on incident wave trains with different wave height.