Simulating cold shear flows on a moving mesh

Abstract

Rotationally supported, cold, gaseous disks are ubiquitous in astrophysics and appear in a diverse set of systems, such as protoplanetary disks, accretion disks around black holes, or large spiral galaxies. Capturing the gas dynamics accurately in these systems is challenging in numerical simulations due to the low sound speed compared to the bulk velocity of the gas, the resolution limitations of full disk models, and the fact that numerical noise can easily source spurious growth of fluid instabilities if not suppressed sufficiently well, negatively interfering with real physical instabilities present in such disks (like the magneto-rotational instability). Here we implement the so-called shearing-box approximation in the moving-mesh code AREPO in order to facilitate achieving high resolution in local regions of differentially rotating disks and to address these problems. While our new approach offers manifest translational invariance across the shearing-box boundaries and offers continuous local adaptivity, we demonstrate that the unstructured mesh of AREPO introduces unwanted levels of "grid-noise" in the default version of the code. We show that this can be rectified by high-order integrations of the flux over mesh boundaries. With our new techniques we obtain highly accurate results for shearing-box calculations of the magneto-rotational instability that are superior to other Lagrangian techniques. These improvements are also of value for other applications of the code that feature strong shear flows.

arXiv comment19 pages, 16 figures, accepted by MNRAS

References in corpus (29)

• E pur si muove: Galiliean-invariant cosmological hydrodynamical simulations on a moving mesh
• PLUTO: a Numerical Code for Computational Astrophysics
• GIZMO: A New Class of Accurate, Mesh-Free Hydrodynamic Simulation Methods
• Athena: A New Code for Astrophysical MHD
• Rossby Wave Instability of Keplerian Accretion Disks
• A High Order Godunov Scheme with Constrained Transport and Adaptive Mesh Refinement for Astrophysical MHD
• The Arepo public code release
• Improving the convergence properties of the moving-mesh code AREPO
• Simulations of magnetic fields in isolated disk galaxies
• Inviscid SPH
• Magnetohydrodynamics on an unstructured moving grid
• MHD simulations of the magnetorotational instability in a shearing box with zero net flux. II. The effect of transport coefficients
• MHD simulations of the magnetorotational instability in a shearing box with zero net flux. I. The issue of convergence
• Moving mesh cosmology: numerical techniques and global statistics
• The Pencil Code, a modular MPI code for partial differential equations and particles: multipurpose and multiuser-maintained
• Convective Overstability in radially stratified accretion disks under thermal relaxation
• Implementation of the Shearing Box Approximation in Athena
• Saturation of the magnetorotational instability in the unstratified shearing box with zero net flux: convergence in taller boxes
• Three Dimensional Compressible Hydrodynamic Simulations of Vortices in Disks
• Linear Theory of Thin, Radially-Stratified Disks
• On the viability of the shearing box approximation for numerical studies of MHD turbulence in accretion disks
• An Exact, Three-Dimensional, Time-Dependent Wave Solution in Local Keplerian Flow
• Global simulations of self-gravitating magnetized protoplanetary disks
• Magnetorotational instability and dynamo action in gravitoturbulent astrophysical discs
• Gravitoturbulent dynamos in astrophysical discs
• Shearingbox-implementation for the central-upwind, constraint-transport MHD-code NIRVANA
• Local simulations of MRI turbulence with meshless methods
• Magnetorotational instability with smoothed particle hydrodynamics
• Magnetohydrodynamic Shearing Waves

Cited by in corpus (5)

• Simulating the magnetorotational instability on a moving mesh with the shearing box approximation
• Gravito-turbulence in local disk simulations with an adaptive moving mesh
• Zooming in on the Circumgalactic Medium with GIBLE: Tracing the Origin and Evolution of Cold Clouds
• Measuring the Numerical Viscosity in Simulations of Protoplanetary Disks in Cartesian Grids -- The Viscously Spreading Ring Revisited
• Multigroup Radiation Diffusion on a Moving Mesh: Implementation in RICH and Application to Tidal Disruption Events