Influence of adaptive mesh refinement and the hydro solver on shear-induced mass stripping in a minor-merger scenario

• Verfasst von: Schmidt, Wolfgang [VerfasserIn]
• Verfasst von: Schulz, Jochen [VerfasserIn]
• Verfasst von: Iapichino, Luigi [VerfasserIn]
• Verfasst von: Vazza, Franco [VerfasserIn]
• Verfasst von: Almgren, Ann S. [VerfasserIn]
• Titel: Influence of adaptive mesh refinement and the hydro solver on shear-induced mass stripping in a minor-merger scenario
• Verf.angabe: W. Schmidt, J. Schulz, L. Iapichino, F. Vazza, A.S. Almgren
• Jahr: 2015
• Jahr des Originals: 2014
• Umfang: 15 S.
• Fussnoten: Available online 21 November 2014 ; Gesehen am 06.07.2020
• Titel Quelle: Enthalten in: Astronomy and computing
• Ort Quelle: Amsterdam [u.a.] : Elsevier, 2013
• Jahr Quelle: 2015
• Band/Heft Quelle: 9(2015), Seite 49-63
• ISSN Quelle: 2213-1337
• DOI: doi:10.1016/j.ascom.2014.11.003
• Datenträger: Online-Ressource
• Sprache: eng
• Sach-SW: Adaptive mesh refinement
• Sach-SW: Hydrodynamics
• Sach-SW: Instabilities
• Sach-SW: Intracluster medium
• Sach-SW: Turbulence
• K10plus-PPN: 1703779215

Abstract

We compare two different codes for simulations of cosmological structure - formation to investigate the sensitivity of hydrodynamical instabilities - to numerics, in particular, the hydro solver and the application of - adaptive mesh refinement (AMR). As a simple test problem, we consider an - initially spherical gas cloud in a wind, which is an idealized model for - the merger of a subcluster or galaxy with a big cluster. Based on an - entropy criterion, we calculate the mass stripping from the subcluster - as a function of time. Moreover, the turbulent velocity field is - analyzed with a multi-scale filtering technique. We find remarkable - differences between the commonly used PPM solver with directional - splitting in the ENZO code and an unsplit variant of PPM in the NYX - code, which demonstrates that different codes can converge to - systematically different solutions even when using uniform grids. For - the test case of an unbound cloud, AMR simulations reproduce - uniform-grid results for the mass stripping quite well, although the - flow realizations can differ substantially. If the cloud is bound by a - static gravitational potential, however, we find strong sensitivity to - spurious fluctuations which are induced at the cutoff radius of the - potential and amplified by the bow shock. This gives rise to substantial - deviations between uniform-grid and AMR runs performed with ENZO, while - the mass stripping in NYX simulations of the subcluster is nearly - independent of numerical resolution and AMR. Although many factors - related to numerics are involved, our study indicates that unsplit - solvers with advanced flux limiters help to reduce grid effects and to - keep numerical noise under control, which is important for - hydrodynamical instabilities and turbulent flows.