orb5x::CollisionsModule Class Reference

Applies linearized and nonlinear Langevin representations of the Landau collision operator. More...

#include "collisions.hpp"

Static Public Member Functions
static void	collisions_disp ()
	Apply every enabled inter- and intraspecies collision pair for one collision step.
static void	destroyStaticViews ()
	Release all collision-owned Kokkos allocations before Kokkos::finalize().
static void	get_bin_momentum (int isp, Real st, Real chit, Real phit, Real &Nval, Real &Vpval, Real &Tval, Real &qpval)
	Interpolate collision-bin density, parallel flow, temperature, and heat flux.
static void	init_collisions ()
	Allocate collision-bin moments, conservation matrices, and random-kick arrays.
static Real	rosenbluth_H (Real x)
	Evaluate the Maxwellian Rosenbluth function \(H(x)\).
static Real	rosenbluth_K (Real x)
	Evaluate the Maxwellian Rosenbluth function \(K(x)\).

Detailed Description

Applies linearized and nonlinear Langevin representations of the Landau collision operator.

Velocity-space stochastic kicks describe test-particle scattering against a local Maxwellian background. Optional field-particle moment corrections restore the discretely conserved density, parallel momentum, and energy in radial/poloidal/toroidal collision bins. Species indices are zero-based and velocities, frequencies, and moments use ORB5X normalization.

Scientific reference

See the ORB5 review manuscript, sections/gk_model.tex, collision model and Rosenbluth-potential equations, and Vernay et al. (2010) cited there.

Fortran reference collisions.F90, module collisions_mod.

Member Function Documentation

collisions_disp()

static void orb5x::CollisionsModule::collisions_disp ( )

static

Apply every enabled inter- and intraspecies collision pair for one collision step.

Selects the linear/nonlinear operator and moment correction from input state.

Fortran reference collisions.F90:collisions_disp.

destroyStaticViews()

static void orb5x::CollisionsModule::destroyStaticViews ( )

static

Release all collision-owned Kokkos allocations before Kokkos::finalize().

get_bin_momentum()

static void orb5x::CollisionsModule::get_bin_momentum ( int  isp, Real  st, Real  chit, Real  phit, Real &  Nval, Real &  Vpval, Real &  Tval, Real &  qpval  )

static

Interpolate collision-bin density, parallel flow, temperature, and heat flux.

Parameters

[in]	isp	Zero-based species index.
[in]	st	Radial coordinate \(s\).
[in]	chit	Poloidal coordinate [rad].
[in]	phit	Toroidal coordinate [rad].
[out]	Nval	Marker density moment.
[out]	Vpval	Parallel-flow moment.
[out]	Tval	Temperature/energy moment.
[out]	qpval	Parallel heat-flux moment.

init_collisions()

static void orb5x::CollisionsModule::init_collisions ( )

static

Allocate collision-bin moments, conservation matrices, and random-kick arrays.

Fortran reference collisions.F90:init_collisions.

rosenbluth_H()

static Real orb5x::CollisionsModule::rosenbluth_H ( Real  x )

static

Evaluate the Maxwellian Rosenbluth function \(H(x)\).

Parameters

[in]

x

Speed divided by the background thermal-speed scale.

Returns

Dimensionless \(H\) coefficient used in drag and diffusion.

rosenbluth_K()

static Real orb5x::CollisionsModule::rosenbluth_K ( Real  x )

static

Evaluate the Maxwellian Rosenbluth function \(K(x)\).

Parameters

[in]

x

Speed divided by the background thermal-speed scale.

Returns

Dimensionless \(K\) coefficient used in pitch-angle diffusion.

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The documentation for this class was generated from the following file:

• collisions.hpp