File braginskii_collisions.hxx

Defines

COLLISIONS_H

struct BraginskiiCollisions : public Component

#include <braginskii_collisions.hxx>

Calculates the collision rate of each species with all other species, using the Braginskii equation.

Important: Be careful when including both ion_neutral collisions and reactions such as charge exchange, since that may result in double counting. Similarly for electron_neutral collisions and ionization reactions.

Public Functions

BraginskiiCollisions(const std::string &name, Options &alloptions, Solver*)

The following boolean options under alloptions[name] control which collisions are calculated:

• electron_electron

• electron_ion

• electron_neutral

• ion_ion

• ion_neutral

• neutral_neutral

The user can also set

• ei_multiplier arbitrary multiplier on electron-ion collision rate

Parameters:

alloptions – Settings, which should include:

• units

  • eV

  • inv_meters_cubed

  • meters

  • seconds

virtual void outputVars(Options &state) override

Add extra fields for output, or set attributes e.g docstrings.

Private Functions

virtual void transform_impl(GuardedOptions &state) override

The implementation of the transform method. Modify the given simulation state. All components must implement this function. It will only allow the reading from/writing to state variables with the appropriate permissiosn in state_variable_access.

void collide(GuardedOptions &species1, GuardedOptions &species2, const Field3D &nu_12)

Update collision frequencies, momentum and energy exchange nu_12 normalised frequency

Calculate apply collision data for the two species. nu_12 normalised frequency

Modifies species1 and species2

• collision_frequency

Note: A* variables are used for atomic mass numbers; mass* variables are species masses in kg

Private Members

BoutReal Tnorm

BoutReal Nnorm

BoutReal rho_s0

BoutReal Omega_ci

bool electron_electron

Which types of collisions to include?

bool electron_ion

bool electron_neutral

bool ion_ion

bool ion_neutral

bool neutral_neutral

BoutReal ei_multiplier

Options collision_rates

Calculated collision rates saved for post-processing and use by other components Saved in options, the BOUT++ dictionary-like object

bool diagnose

Save more diagnostics?