Enhanced performances of an improved SPH scheme in a variety of hydrodynamical test cases

by Riccardo Valdarnini (SISSA, Trieste)

Friday 16 Dec 2016, 10:30 → 11:30 Europe/Stockholm

FC61

Is now widely recognized that the Lagrangian SPH code, in its standard formulation, suffers from a number of shortcomings when simulating several hydrodynamical test cases. Specifically, for these tests it is found that there are significant differences when contrasting the simulations results against those obtained using Eulerian mesh-based codes. Because of its very good conservation properties, many authors have proposed several improvements in the SPH numerical scheme aimed at solving the problems encountered by standard SPH. Here I present results obtained using some improvements in the SPH formulation. In the first part it is introduced an SPH scheme employing an artificial conductivity (AC) term. For a set of simulated galaxy clusters are then discussed the effects on the thermal structure of the ICM due to this term, and its observational consequences. In the second part I present results from a number of tests performed in the subsonic flow regime, in which SPH gradients are estimated using an Integral Approximation. It is found that the new scheme systematically outperforms standard SPH and is competitive with other numerical schemes recently proposed. In particular, for a given resolution, the new scheme exhibits in subsonic turbulence power spectra with a much larger inertial range than in the standard case.