J/A+A/631/A41 Radiation module for the code PLUTO (Colombo+, 2019)
Non-LTE radiation hydrodynamics in PLUTO.
Colombo S., Ibgui L., Orlando S., Rodriguez R., Espinosa G., Gonzalez M.,
Stehle C., Peres G.
<Astron. Astrophys. 631, A41 (2019)>
=2019A&A...631A..41C 2019A&A...631A..41C (SIMBAD/NED BibCode)
ADC_Keywords: Models
Keywords: radiation dynamics = hydrodynamics - opacity
Abstract:
Modeling the dynamics of most astrophysical structures requires an
adequate description of the interaction of radiation and matter.
Several numerical (magneto-) hydrodynamics codes were upgraded with a
radiation module to fulfill this request. However, those that used
either the flux-limited diusion (FLD) or the M1 radiation moment
approaches are restricted to local thermodynamic equilibrium (LTE).
This assumption may not be valid in some astrophysical cases.
We present an upgraded version of the LTE radiation-hydrodynamics
(RHD) module implemented in the PLUTO code, which we have extended to
handle non-LTE regimes.
Starting from the general frequency-integrated comoving-frame
equations of RHD, we have justified all the assumptions that were made
to obtain the non-LTE equations that are implemented in the module
under the FLD approximation. An operator-split method with two
substeps was employed: the hydrodynamics part was solved with an
explicit method by the solvers that are currently available in PLUTO,
and the non-LTE radiation diusion and energy exchange part was solved
with an implicit method. The module was implemented in the PLUTO
environment. It uses databases of radiative quantities that can be
provided independently by the user: the radiative power loss, and the
Planck and Rosseland mean opacities. In our case, these quantities
were determined from a collisional-radiative steady-state model, and
they are tabulated as functions of temperature and density.
Our implementation has been validated through dierent tests, in
particular, radiative shock tests. The agreement with the
semi-analytical solutions (when available) is good, with a maximum
error of 7%. Moreover, we have proved that a non-LTE approach is of
paramount importance to properly model accretion shock structures.
Our radiation FLD module represents a step toward a general non-LTE
RHD modeling. The module is available for the community upon request.
Description:
PLUTO is a freely-distributed software for the numerical solution of
mixed hyperbolic/parabolic systems of partial differential equations
(conservation laws) targeting high Mach number flows in astrophysical
fluid dynamics. The code is designed with a modular and flexible
structure whereby different numerical algorithms can be separately
combined to solve systems of conservation laws using the finite volume
or finite difference approach based on Godunov-type schemes.
See http://plutocode.ph.unito.it/ and
http://cerere.astropa.unipa.it/progetti_ricerca/HPC/resources.htm
for more details.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
radiation_module-1.1.patch 568 15613 Radiation module for the code
PLUTO
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History:
Copied at http://www.tat.physik.uni-tuebingen.de/~pluto/pluto_radiation/
(End) Patricia Vannier [CDS] 23-Sep-2019