File snb.hxx#

namespace bout

Provides access to the Hypre library, handling initialisation and finalisation.


#include <bout/hyprelib.hxx>

class MyClass { public:

private: HypreLib lib; };

This will then automatically initialise Hypre the first time an object is created, and finalise it when the last object is destroyed.

Copyright 2012 B.D.Dudson, S.Farley, M.V.Umansky, X.Q.Xu

Contact: Ben Dudson,

This file is part of BOUT++.

BOUT++ is free software: you can redistribute it and/or modify it under the terms of the GNU Lesser General Public License as published by the Free Software Foundation, either version 3 of the License, or (at your option) any later version.

BOUT++ is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License for more details.

You should have received a copy of the GNU Lesser General Public License along with BOUT++. If not, see

Information about the version of BOUT++

The build system will update this file on every commit, which may result in files that include it getting rebuilt. Therefore it should be included in as few places as possible

Information about the version of BOUT++

The build system will update this file at configure-time

SNB model

class HeatFluxSNB#
#include <snb.hxx>

Calculate heat flux using the Shurtz-Nicolai-Busquet (SNB) model

Useful references:

Braginskii equations by R.Fitzpatrick:

J.P.Brodrick et al 2017: and

Shurtz, Nicolai and Busquet 2000:

Public Functions

inline HeatFluxSNB()#

Construct using the options in the “snb” section.

inline explicit HeatFluxSNB(Options &options)#

Construct using options in given section.

~HeatFluxSNB() = default#
HeatFluxSNB(HeatFluxSNB&&) = default#
HeatFluxSNB &operator=(HeatFluxSNB&&) = default#
HeatFluxSNB(const HeatFluxSNB&) = delete#
HeatFluxSNB &operator=(const HeatFluxSNB&) = delete#
Field3D divHeatFlux(const Field3D &Te, const Field3D &Ne, Field3D *Div_Q_SH_out = nullptr)#

Calculate divergence of heat flux Te: Electron temperature in eV Ne: Electron density in m^-3

Div_Q_SH_out : An optional output field to store the Spitzer-Harm heat flux

Returns the divergence of heat flux in units of eV per cubic meter per second -> multiply by e=1.602e-19 to get Watts per cubic meter.

Private Functions

inline BoutReal int_beta4_exp(BoutReal beta)#

Indefinite integral of beta^4 * exp(-beta) with constant set to zero

inline BoutReal groupWeight(BoutReal beta_min, BoutReal beta_max)#

(1/24) * Integral of beta^4 * exp(-beta) from beta_min to beta_max

Private Members

std::unique_ptr<InvertParDiv> invertpardiv = {nullptr}#

Parallel inversion of tridiagonal matrices.

BoutReal Z = {1}#

Average ion charge (1 = Hydrogen)

BoutReal r = {2}#

Electron-electron mean free path scaling factor.

BoutReal beta_max = {10.0}#

Maximum energy group to consider (multiple of eT)

int ngroups = {40}#

Number of energy groups.