Mancha3D (Multi-physics Advanced Non-ideal Code for High-resolution simulations of the solar Atmosphere)

Mancha3D is a versatile numerical code for modeling of the solar and stellar atmospheres. The code solves time-dependent equations of the magnetohydrodynamics (MHD) on 3D Cartesian grid. Depending on the setup, \mancha can solve either full or linearized MHD equations. In addition to the set of MHD equations, there are various terms and modules available: non-ideal terms (ambipolar diffusion, Hall's term and Biermann's battery), radiative transfer equation, realistic equation of state. The code is written in modern Fortran language and fully parallelized (spatial domain decomposition) using the MPI library.

The name Mancha goes back to the earliest version of the code that was designed to simulate propagation of waves in sunspots ("mancha solar'' means sunspot in Spanish). Written in all capitals, it is an acronym for Multi-fluid (-purpose, -physics, -dimensional) Advanced Non-ideal MHD Code for High-res simulations of the solar Atmosphere.

The earliest version of Mancha (2D prototype) was written by Elena Khomenko and Manolo Collados in 2004--2006 for the purpose of wave simulation in sunspots (Khomenko & Collados, 2006). The initial code was extended to 3D and paralellized by Tobias Felipe (Felipe et al., 2010, see also PhD thesis of T. Felipe). In the framework of the ERC supported SPIA project (2012--2016), Mancha parallelization and numerical performance was optimized (Angel de Vicente), variables changed from adimensional to having physical units and non-ideal terms were implemented (Khomenko & Collados, 2012), 3D aspects were improved (Manuel Luna), radiative transfer and equation of state were added (Nikola Vitas), (see Vitas & Khomenko, 2015, Khomenko et al., 2017, Khomenko et al., 2018). Finally, a super-time stepping scheme is incorporated (P. González-Morales et al., 2018, see also P. González-Morales PhD thesis, 2020). Within the the PI2FA ERC project, some numerical treatments are improved, the code is cleaned and further optimized (Nikola Vitas, Mikhail Modestov), further setups are designed (David Martinez, Andrea Perdomo, Valeria Liakh) and the thermal conduction module is developed (Anamaria Navarro).

The main features of the code are:

  • Solves non-linear non-ideal MHD equations for perturbations in 3D;
  • Magneto-static equilibrium is explicitly removed from the equations;
  • Ambipolar diffusion, Hall and Biermann battery effects from generalized Ohm’s law;
  • 4th order in space and time; STS for Ambipolar diffusion; HDS for Hall effect
  • Stabilized by hyper-diffusive terms;
  • PML absorption layer boundary conditions;
  • Energy losses according LTE RT;
  • Realistic equation of state for solar chemical mixture;
  • MPI parallelized using domain decomposition, up to 80% efficiency for 4000 CPUs
Mancha code is distributed via private Gitlab repository. In order to get access to the code a new user should register at gitlab.com and fill the registration form. All the requests are handled manually, You will be contacted within a few days with further instractions. 
 

Mancha-TwoFluid

The two-fluid code represents an extension of the existing Mancha3D code. 

The code solves two-fluid equations of conservation of mass, momentum and energy, together with the induction equation, for the case of the purely hydrogen plasma with collisional coupling between the charged and neutral fluid components, and with inclusion of physical viscosity and thermal conductivity. The implementation of a semi-implicit algorithm allows to overcome the numerical stability constraints due to the stiff collisional terms. Viscosity and thermal conduction are treated implicitly using the BiCGStab algorithm.

 

References

  • Khomenko, E.; Collados, M. "Numerical Modeling of Magnetohydrodynamic Wave Propagation and Refraction in Sunspots", 2006, The Astrophysical Journal, Volume 653, Issue 1, pp. 739-755, 2006ApJ...653..739K
  • Felipe, T.; Khomenko, E.; Collados, M. "Magneto-acoustic Waves in Sunspots: First Results From a New Three-dimensional Nonlinear Magnetohydrodynamic Code", 2010, The Astrophysical Journal, Volume 719, Issue 1, pp. 357-377, 2010ApJ...719..357F
  • Khomenko, E.; Collados, M. "Heating of the Magnetized Solar Chromosphere by Partial Ionization Effects", 2012, The Astrophysical Journal, Volume 747, Issue 2, article id. 87, 2012ApJ...747...87K
  • Vitas, N.; Khomenko, E. "Equation of state for solar near-surface convection", 2015, Annales Geophysicae, Volume 33, Issue 6, 2015, pp.703-709, 2015AnGeo..33..703V
  • González-Morales, P. A.; Khomenko, E.; Downes, T. P.; de Vicente, A. "MHDSTS: a new explicit numerical scheme for simulations of partially ionised solar plasma", 2018, Astronomy & Astrophysics, Volume 615, id.A67, 2018A%26A...615A..67G
  • Khomenko, E.; Vitas, N.; Collados, M.; de Vicente, A. "Three-dimensional simulations of solar magneto-convection including effects of partial ionization", 2018, Astronomy & Astrophysics, Volume 618, id.A87, 2018A%26A...618A..87K
  • Popescu Braileanu, B.; Lukin, V. S.; Khomenko, E.; de Vicente, A. "Two-fluid simulations of waves in the solar chromosphere I: numerical code verification", 2019, Astronomy & Astrophysics, in press, 2019arXiv190503559P