Module containing the global data and variables for the neutral particle recycling model. More...

Functions/Subroutines
subroutine	set_neutral_pointers (nnode, nwall, nebin, neu_weight_wall_lost_in, neu_weight_sum_lost_in, neu_weight_lost_ebins_in, neu_node_dens_in, neu_node_temp_in)

Variables
integer	neu_num =10000
	Number of neutral particles per thread per wall segment. If neu_degas2=.true., this is the number of neutral particles per thread. More...

integer	neu_istep_max =20000
	Maximum number of neutral push time steps. More...

integer	neu_accum_time =0
	Integer number of timesteps over which the total number of recycling ions have been building up on the wall as neu_weight_sum_lost. More...

integer	neu_tot_accum_time =0
	Integer number of timesteps over which the recycling profile has been building over neu_background_period timesteps. More...

logical	neu_enforce_no_neutral =.false.
	Forced off-switch for the neutral recycling routine (needed for radiation cooling!) More...

logical	neu_adjust_n0 =.true.
	whether to update the base neutral density. If true, a provisional ionization rate (everywhere proportional to the local neutral density) is rescaled to match the global particle sink from the sheath module times neu_recycle_rate. .false. fixed n0, .true. varying n0 - neu_recycle_rate should be specified. More...

real(kind=8)	neu_n0 =5.0D17
	m^-3 -> nomalized unit, Realistic initial value for neu_base_den (=base neutral density). For cases where neu_adjust_n0=false, this provides a baseline density to use. When neu_adjust_n0=true, neu_base_den is still calculated and reported in the stdout log, but has no effect on the physics. More...

real(kind=8)	neu_temp0 =3D0
	Neutral temperature boundary condition. More...

real(kind=8)	neu_dt
	Timestep size for the neutral Monte Carlo steps. If not provided, a default value of 2e-3sml_dt/sqrt(neu_temp01e-3) is used. More...

real(kind=8)	neu_base_den
	Base multiplier for the neutral density. Uses neu_n0. More...

logical	neu_degas2 =.false.
	Use DEGAS2 for the neutral Monte Carlo calculation. More...

integer	neu_ebin_num =10
	Number of energy bins to use for neutral source. More...

real(kind=8)	neu_ebin_min =3.0
	Lower bound of the smallest energy bin (in eV) More...

real(kind=8)	neu_ebin_max =13.0
	Lower bound of the smallest energy bin (in eV) More...

logical	neu_ebin_log = .false.
	Whether recycling energy bins are logarithmcially spaced. More...

real(kind=8)	neu_ebin_delta
	Number of energy bins to use for neutral source. More...

integer	neu_d2_ran_k =100
	The ran_k parameter from DEGAS2's random.hweb. Unlikely to change. More...

integer	neu_d2_nsp_plas = 2
	Number of plasma species in the DEGAS2 problem file. Unlikely to change without more data. More...

integer	neu_d2_nsp_neut = 1
	Number of neutral species in the DEGAS2 problem file, including the geometric dummy species '0'. The first nontrivial species is the one whose density and temperature will be calculated. More...

integer, dimension(:), allocatable	neu_d2_sp_map
	Mapping of species indexing between XGC and DEGAS2. More...

integer	neu_d2_first_wall_idx
	Index of wall_nodes_ordered that the DEGAS2 setup uses as the first one. More...

real(kind=8)	neu_gas_puff_source = -1.0
	Source of additional neutrals in particles/s. Disables neu_adjust_n0. Also, puffed neutrals enter at the lowest energy bin. More...

integer	neu_gas_puff_segment = -1
	Index of wall_nodes_ordered from which neu_gas_puff_source is produced. More...

real(kind=8), dimension(:), pointer	neu_weight_sum_lost
	Global number of ions lost to the wall. More...

real(kind=8)	neu_weight_lost_max = 5D23
	upper cutoff on the number of lost particles More...

real(kind=8)	neu_lost_rate_max =5D23
	upper cutoff on the particle loss rate (particles/sec) More...

real(kind=8)	neu_recycle_rate =0.9D0
	Fraction of lost ions that are recycled as neutrals. The ions lost to the wall as calculated in the sheath module are used to determine the global particle sink. Neutrals are produced at a rate of neu_recycle_rate*neu_sum_weight_lost (in particles per second). Has no effect if neu_adjust_n0=false. More...

real(kind=8)	neu_theta_x = -99D0

real(kind=8)	neu_peak_theta =-99D0
	Poloidal angle at which the neutral source is peak for neu_source_match_flux=.false. More...

real(kind=8)	neu_delta_n =10D0
	Multiple of base neutral density at the peak position. When neu_source_match_flux=.false., determines the shape of the poloidal neutral source distribution. At large neu_delta_n, it approaches a Gaussian. neu_delta_n=1.0 corresponds to a uniform neutral source. More...

real(kind=8)	neu_delta_theta =0.5235987756
	Width of the peak of the neutral source for neu_source_match_flux=.false. - 30/180 * pi. More...

real(kind=8)	neu_inpsi =0.7D0
	Inner boundary for neutral fueling calculation (normalized pol. flux) More...

integer	neu_background_period =500
	Period between subsequent updates of the background neutral distribution function in ion time steps. In any case, the density renormalization and source rates are recalculated every timestep for a fixed normalized neutral profile. More...

logical	neu_exclude_private =.false.
	Exclude the privat region from neutral recycling. More...

real(kind=8), dimension(:), allocatable	neu_ebins

real(kind=8), dimension(:), allocatable	neu_wall_source
	Source of neutrals around limiter. More...

real(kind=8), dimension(:,:), allocatable	neu_wall_source_ebins
	Source of neutrals around limiter. More...

real(kind=8), dimension(:), pointer	neu_weight_wall_lost
	Local number of ions lost to the wall. More...

real(kind=8), dimension(:,:), pointer	neu_weight_lost_ebins
	Local number of ions lost to the wall. More...

real(kind=8), dimension(:,:), allocatable	neu_norm_baseden_ebins
	Holds normalized neutral density from ion flux to wall, energy binned. More...

real(kind=8), dimension(:,:), allocatable	neu_d2_n0
	DEGAS2-predicted neutral density. More...

real(kind=8), dimension(:,:,:), allocatable	neu_d2_v0
	DEGAS2-predicted neutral velocity. More...

real(kind=8), dimension(:,:), allocatable	neu_d2_t0
	DEGAS2-predicted neutral temperature. More...

real(kind=8), dimension(:,:,:), allocatable	neu_d2_sources
	DEGAS2-predicted sources for each species from neutral interactions. More...

real(kind=8), dimension(:,:), allocatable	neu_d2_sourcetot
	DEGAS2-predicted sources integrated over whole volume. More...

integer	neu_d2_ran_idx

real(kind=8), dimension(:), allocatable	neu_d2_rand_array
	An array for random numbers in DEGAS2. More...

integer	neu_nnode
	Number of nodes in neutral solution volume. Currently gridnnode. More...

integer	neu_nbirth
	Number of birth locations. Currently gridnwall. More...

logical	neu_source_match_flux =.true.
	If true, the neutral source around the limiter is determined from the local ion sink. If false, the neutral source is given an analytic poloidal dependence. More...

real(kind=8), dimension(:), allocatable	neu_rbirth

real(kind=8), dimension(:), allocatable	neu_zbirth
	(R,Z) coordinates of the neutral birth surface More...

real(kind=8), dimension(:), pointer	neu_node_dens
	Normalized neutral density. More...

real(kind=8), dimension(:), pointer	neu_node_temp
	Neutral temperature. More...

real(kind=8), dimension(:), allocatable	neu_node_wsum
	Weight sum for neutral density calculation. More...

real(kind=8), dimension(:), allocatable	neu_node_esum
	Weight sum for avg. neutral energy calculation. More...

real(kind=8), dimension(:), allocatable	neu_node_varsum
	Weight sum for weight variance calculation. More...

real(kind=8), dimension(:), allocatable	neu_node_numsum
	Weight sum for neutral number calculation. More...

real(kind=8), dimension(:), allocatable	neu_node_vol
	Neutral cell volume. More...

real(kind=8), dimension(:), allocatable	neu_node_flow
	Neutral bulk flow. More...

real(kind=8), dimension(:), allocatable	neu_node_vsum
	Weight sum for neutral bulk flow calculation. More...

real(kind=8), dimension(:), allocatable	neu_node_relstd
	Neutral weight standard deviation. More...

Detailed Description

Module containing the global data and variables for the neutral particle recycling model.

Function/Subroutine Documentation

◆ set_neutral_pointers()

subroutine neu_module::set_neutral_pointers	(	integer, intent(in), value	nnode,
		integer, intent(in), value	nwall,
		integer, intent(in), value	nebin,
		real (8), dimension(nwall), target	neu_weight_wall_lost_in,
		real (8), dimension(1), target	neu_weight_sum_lost_in,
		real (8), dimension(nwall,nebin), target	neu_weight_lost_ebins_in,
		real (8), dimension(nnode), target	neu_node_dens_in,
		real (8), dimension(nnode), target	neu_node_temp_in
	)

Variable Documentation

◆ neu_accum_time

integer neu_module::neu_accum_time =0

Integer number of timesteps over which the total number of recycling ions have been building up on the wall as neu_weight_sum_lost.

◆ neu_adjust_n0

logical neu_module::neu_adjust_n0 =.true.

whether to update the base neutral density. If true, a provisional ionization rate (everywhere proportional to the local neutral density) is rescaled to match the global particle sink from the sheath module times neu_recycle_rate. .false. fixed n0, .true. varying n0 - neu_recycle_rate should be specified.

◆ neu_background_period

integer neu_module::neu_background_period =500

Period between subsequent updates of the background neutral distribution function in ion time steps. In any case, the density renormalization and source rates are recalculated every timestep for a fixed normalized neutral profile.

◆ neu_base_den

real (kind=8) neu_module::neu_base_den

Base multiplier for the neutral density. Uses neu_n0.

◆ neu_d2_first_wall_idx

integer neu_module::neu_d2_first_wall_idx

Index of wall_nodes_ordered that the DEGAS2 setup uses as the first one.

◆ neu_d2_n0

real (kind=8), dimension(:,:), allocatable neu_module::neu_d2_n0

DEGAS2-predicted neutral density.

◆ neu_d2_nsp_neut

integer neu_module::neu_d2_nsp_neut = 1

Number of neutral species in the DEGAS2 problem file, including the geometric dummy species '0'. The first nontrivial species is the one whose density and temperature will be calculated.

◆ neu_d2_nsp_plas

integer neu_module::neu_d2_nsp_plas = 2

Number of plasma species in the DEGAS2 problem file. Unlikely to change without more data.

◆ neu_d2_ran_idx

integer neu_module::neu_d2_ran_idx

◆ neu_d2_ran_k

integer neu_module::neu_d2_ran_k =100

The ran_k parameter from DEGAS2's random.hweb. Unlikely to change.

◆ neu_d2_rand_array

real (kind=8), dimension(:), allocatable neu_module::neu_d2_rand_array

An array for random numbers in DEGAS2.

◆ neu_d2_sources

real (kind=8), dimension(:,:,:), allocatable neu_module::neu_d2_sources

DEGAS2-predicted sources for each species from neutral interactions.

◆ neu_d2_sourcetot

real (kind=8), dimension(:,:), allocatable neu_module::neu_d2_sourcetot

DEGAS2-predicted sources integrated over whole volume.

◆ neu_d2_sp_map

integer, dimension(:), allocatable neu_module::neu_d2_sp_map

Mapping of species indexing between XGC and DEGAS2.

◆ neu_d2_t0

real (kind=8), dimension(:,:), allocatable neu_module::neu_d2_t0

DEGAS2-predicted neutral temperature.

◆ neu_d2_v0

real (kind=8), dimension(:,:,:), allocatable neu_module::neu_d2_v0

DEGAS2-predicted neutral velocity.

◆ neu_degas2

logical neu_module::neu_degas2 =.false.

Use DEGAS2 for the neutral Monte Carlo calculation.

◆ neu_delta_n

real (kind=8) neu_module::neu_delta_n =10D0

Multiple of base neutral density at the peak position. When neu_source_match_flux=.false., determines the shape of the poloidal neutral source distribution. At large neu_delta_n, it approaches a Gaussian. neu_delta_n=1.0 corresponds to a uniform neutral source.

◆ neu_delta_theta

real (kind=8) neu_module::neu_delta_theta =0.5235987756

Width of the peak of the neutral source for neu_source_match_flux=.false. - 30/180 * pi.

◆ neu_dt

real (kind=8) neu_module::neu_dt

Timestep size for the neutral Monte Carlo steps. If not provided, a default value of 2e-3*sml_dt/sqrt(neu_temp0*1e-3) is used.

◆ neu_ebin_delta

real (kind=8) neu_module::neu_ebin_delta

Number of energy bins to use for neutral source.

◆ neu_ebin_log

logical neu_module::neu_ebin_log = .false.

Whether recycling energy bins are logarithmcially spaced.

◆ neu_ebin_max

real (kind=8) neu_module::neu_ebin_max =13.0

Lower bound of the smallest energy bin (in eV)

◆ neu_ebin_min

real (kind=8) neu_module::neu_ebin_min =3.0

Lower bound of the smallest energy bin (in eV)

◆ neu_ebin_num

integer neu_module::neu_ebin_num =10

Number of energy bins to use for neutral source.

◆ neu_ebins

real (kind=8), dimension(:), allocatable neu_module::neu_ebins

◆ neu_enforce_no_neutral

logical neu_module::neu_enforce_no_neutral =.false.

Forced off-switch for the neutral recycling routine (needed for radiation cooling!)

◆ neu_exclude_private

logical neu_module::neu_exclude_private =.false.

Exclude the privat region from neutral recycling.

◆ neu_gas_puff_segment

integer neu_module::neu_gas_puff_segment = -1

Index of wall_nodes_ordered from which neu_gas_puff_source is produced.

◆ neu_gas_puff_source

real (kind=8) neu_module::neu_gas_puff_source = -1.0

Source of additional neutrals in particles/s. Disables neu_adjust_n0. Also, puffed neutrals enter at the lowest energy bin.

◆ neu_inpsi

real (kind=8) neu_module::neu_inpsi =0.7D0

Inner boundary for neutral fueling calculation (normalized pol. flux)

◆ neu_istep_max

integer neu_module::neu_istep_max =20000

Maximum number of neutral push time steps.

◆ neu_lost_rate_max

real (kind=8) neu_module::neu_lost_rate_max =5D23

upper cutoff on the particle loss rate (particles/sec)

◆ neu_n0

real (kind=8) neu_module::neu_n0 =5.0D17

m^-3 -> nomalized unit, Realistic initial value for neu_base_den (=base neutral density). For cases where neu_adjust_n0=false, this provides a baseline density to use. When neu_adjust_n0=true, neu_base_den is still calculated and reported in the stdout log, but has no effect on the physics.

◆ neu_nbirth

integer neu_module::neu_nbirth

Number of birth locations. Currently gridnwall.

◆ neu_nnode

integer neu_module::neu_nnode

Number of nodes in neutral solution volume. Currently gridnnode.

◆ neu_node_dens

real (kind=8), dimension(:), pointer neu_module::neu_node_dens

Normalized neutral density.

◆ neu_node_esum

real (kind=8), dimension(:), allocatable neu_module::neu_node_esum

Weight sum for avg. neutral energy calculation.

◆ neu_node_flow

real (kind=8), dimension(:), allocatable neu_module::neu_node_flow

Neutral bulk flow.

◆ neu_node_numsum

real (kind=8), dimension(:), allocatable neu_module::neu_node_numsum

Weight sum for neutral number calculation.

◆ neu_node_relstd

real (kind=8), dimension(:), allocatable neu_module::neu_node_relstd

Neutral weight standard deviation.

◆ neu_node_temp

real (kind=8), dimension(:), pointer neu_module::neu_node_temp

Neutral temperature.

◆ neu_node_varsum

real (kind=8), dimension(:), allocatable neu_module::neu_node_varsum

Weight sum for weight variance calculation.

◆ neu_node_vol

real (kind=8), dimension(:), allocatable neu_module::neu_node_vol

Neutral cell volume.

◆ neu_node_vsum

real (kind=8), dimension(:), allocatable neu_module::neu_node_vsum

Weight sum for neutral bulk flow calculation.

◆ neu_node_wsum

real (kind=8), dimension(:), allocatable neu_module::neu_node_wsum

Weight sum for neutral density calculation.

◆ neu_norm_baseden_ebins

real (kind=8), dimension(:,:), allocatable neu_module::neu_norm_baseden_ebins

Holds normalized neutral density from ion flux to wall, energy binned.

◆ neu_num

integer neu_module::neu_num =10000

Number of neutral particles per thread per wall segment. If neu_degas2=.true., this is the number of neutral particles per thread.

◆ neu_peak_theta

real (kind=8) neu_module::neu_peak_theta =-99D0

Poloidal angle at which the neutral source is peak for neu_source_match_flux=.false.

◆ neu_rbirth

real (kind=8), dimension(:), allocatable neu_module::neu_rbirth

◆ neu_recycle_rate

real (kind=8) neu_module::neu_recycle_rate =0.9D0

Fraction of lost ions that are recycled as neutrals. The ions lost to the wall as calculated in the sheath module are used to determine the global particle sink. Neutrals are produced at a rate of neu_recycle_rate*neu_sum_weight_lost (in particles per second). Has no effect if neu_adjust_n0=false.

◆ neu_source_match_flux

logical neu_module::neu_source_match_flux =.true.

If true, the neutral source around the limiter is determined from the local ion sink. If false, the neutral source is given an analytic poloidal dependence.

◆ neu_temp0

real (kind=8) neu_module::neu_temp0 =3D0

Neutral temperature boundary condition.

◆ neu_theta_x

real (kind=8) neu_module::neu_theta_x = -99D0

◆ neu_tot_accum_time

integer neu_module::neu_tot_accum_time =0

Integer number of timesteps over which the recycling profile has been building over neu_background_period timesteps.

◆ neu_wall_source

real (kind=8), dimension(:), allocatable neu_module::neu_wall_source

Source of neutrals around limiter.

◆ neu_wall_source_ebins

real (kind=8), dimension(:,:), allocatable neu_module::neu_wall_source_ebins