smod_equil_MRI – Legolas v. 2.0.0

This submodule defines magneto-rotational instabilities in an accretion disk. Due to the special nature of this equilibrium x_start is hardcoded to one and can not be overridden in the parfile, the same goes for the geometry which is hardcoded to 'cylindrical'. The outer edge can be chosen freely. This equilibrium is chosen in such a way that the angular rotation is of order unity, implying Keplerian rotation. The thin-disk approximation is valid with small magnetic fields, but still large enough to yield magneto-rotational instabilities. Gravity is assumed to go like $g \thicksim 1/r^2$ .

This equilibrium is taken from section V in Goedbloed, J. P. "The Spectral Web of stationary plasma equilibria. II. Internal modes." Physics of Plasmas 25.3 (2018): 032110. and also appears in section 13.5, fig. 13.7 in Goedbloed, H., Keppens, R., & Poedts, S. (2019). Magnetohydrodynamics of Laboratory and Astrophysical Plasmas. Cambridge University Press. DOI.

Note

Default values are given by

k2 = 0
k3 = 70
beta = 100 : parameter $\beta = 2p_1/B_1^2$ .
tau = 1 : represents parameter $\tau = \mu_1 = B_{\theta 1}/B_{z1}$
nu = 0.1 : represents parameter $\nu = \epsilon = \sqrt{p_1}$
x_end = 2 : fixes the parameter $\delta = x_{end}/x_{start}$

and can all be changed in the parfile.

Uses

- Ancestors:
- mod_equilibrium

Module Procedures

MRI_accretion_eq

Module Procedures

module procedure MRI_accretion_eq module module subroutine MRI_accretion_eq(settings)

Arguments

Type	Intent	Optional	Attributes		Name
type(settings_t),	intent(inout)			::	settings

smod_equil_MRI Submodule

Contents

Module Procedures

Note

Uses

Ancestors:

Contents

Module Procedures

Module Procedures

module procedure MRI_accretion_eq module module subroutine MRI_accretion_eq(settings)

Arguments

smod_equil_MRI Submodule

Contents

Module Procedures

Note

Uses

Ancestors:

Contents

Module Procedures

Module Procedures

module procedure MRI_accretion_eq module module subroutine MRI_accretion_eq(settings) Interface →

Arguments

module procedure MRI_accretion_eq module module subroutine MRI_accretion_eq(settings)