Radiation-Hydrodynamics with MPI-AMRVAC: Flux-Limited Diffusion

Abstract

Radiation controls the dynamics and energetics of many astrophysical environments. To capture the coupling between the radiation and matter, however, is often a physically complex and computationally expensive endeavour. We develop a numerical tool to perform radiation-hydrodynamics simulations in various configurations at an affordable cost. We build upon the finite volume code MPI-AMRVAC to solve the equations of hydrodynamics on multi-dimensional adaptive meshes and introduce a new module to handle the coupling with radiation. A non-equilibrium, flux-limiting diffusion approximation is used to close the radiation momentum and energy equations. The time-dependent radiation energy equation is then solved within a flexible framework, accounting fully for radiation forces and work terms and further allowing the user to adopt a variety of descriptions for the radiation-matter interaction terms (the 'opacities'). We validate the radiation module on a set of standard testcases for which different terms of the radiative energy equation predominate. As a preliminary application to a scientific case, we calculate spherically symmetric models of the radiation-driven and optically thick supersonic outflows from massive Wolf-Rayet stars. This also demonstrates our code's flexibility, as the illustrated simulation combines opacities typically used in static stellar structure models with a parametrised form for the enhanced line-opacity expected in supersonic flows. This new module provides a convenient and versatile tool to perform multi-dimensional and high resolution radiative-hydrodynamics simulations in optically thick environments with the MPI-AMRVAC code. The code is ready to be used for a variety of astrophysical applications, where a first target for us will be multi-dimensional simulations of stellar outflows from Wolf-Rayet stars.

14 pages, 10 figures Submitted to A&A

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Cited by in corpus (16)

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• MPI-AMRVAC 3.0: updates to an open-source simulation framework
• First 3D Radiation-Hydrodynamic Simulations of Wolf-Rayet Winds
• VETTAM: A scheme for radiation hydrodynamics with adaptive mesh refinement using the variable Eddington tensor method
• Radiation transport methods in star formation simulations
• Method and new tabulations for flux-weighted line-opacity and radiation line-force in supersonic media
• Theoretical wind clumping predictions from 2D LDI models of O-star winds at different metallicities
• Three Dimensional Natures of Massive Star Envelopes
• The Maximum Black Hole Mass at Solar Metallicity
• Improving 1D stellar atmosphere models with insights from multi-dimensional simulations I. 1D vs 2D stratifications and spectral comparison for O stars
• Radiative Transfer as a Bayesian Linear Regression problem
• An on-the-fly line-driven-wind iterative mass-loss estimator (LIME) for hot, massive stars of arbitrary chemical compositions
• Improving 1D stellar atmosphere models with insights from multi-dimensional simulations II. 1D versus 3D hydrodynamically consistent model comparison for WR stars
• Radiation-magnetohydrodynamics with MPI-AMRVAC using flux-limited diffusion
• Structure formation in O-type stars and Wolf-Rayet stars
• HARD: A Performance Portable Radiation Hydrodynamics Code based on FleCSI Framework