nx = 64
ny = 64
xmin = -20.e-6
ymin = -20.e-6
xmax = +20.e-6
ymax = +20.e-6
uniform_plasma = picmi.UniformDistribution(
density=1.e25,
upper_bound=[0., None, None],
directed_velocity=[0.1 * constants.c, 0., 0.])
electrons = picmi.Species(particle_type='electron',
name='electrons',
initial_distribution=uniform_plasma)
grid = picmi.Cartesian2DGrid(
number_of_cells=[nx, ny],
lower_bound=[xmin, ymin],
upper_bound=[xmax, ymax],
lower_boundary_conditions=['periodic', 'periodic'],
upper_boundary_conditions=['periodic', 'periodic'],
moving_window_velocity=[0., 0., 0.],
warpx_max_grid_size=32)
solver = picmi.ElectromagneticSolver(grid=grid, cfl=1.)
sim = picmi.Simulation(solver=solver,
max_steps=40,
uniform_plasma_elec = picmi.UniformDistribution(
density = PLASMA_DENSITY,
upper_bound = [None] * 3,
rms_velocity = [v_rms_elec] * 3,
directed_velocity = [0.] * 3
)
uniform_plasma_ion = picmi.UniformDistribution(
density = PLASMA_DENSITY,
upper_bound = [None] * 3,
rms_velocity = [v_rms_ion] * 3,
directed_velocity = [0.] * 3
)
electrons = picmi.Species(
particle_type='electron', name='electrons',
initial_distribution=uniform_plasma_elec
)
ions = picmi.Species(
particle_type='He', name='he_ions',
charge='q_e',
initial_distribution=uniform_plasma_ion
)
# MCC collisions
cross_sec_direc = '../../../../warpx-data/MCC_cross_sections/He/'
mcc_electrons = picmi.MCCCollisions(
name='coll_elec',
species=electrons,
background_density=N_INERT,
background_temperature=T_INERT,
background_mass=ions.mass,
solver = picmi.ElectromagneticSolver(grid=grid, cfl=1)
beam_distribution = picmi.UniformDistribution(
density=1.e23,
lower_bound=[-20.e-6, -20.e-6, -150.e-6],
upper_bound=[+20.e-6, +20.e-6, -100.e-6],
directed_velocity=[0., 0., 1.e9])
plasma_distribution = picmi.UniformDistribution(
density=1.e22,
lower_bound=[-200.e-6, -200.e-6, 0.],
upper_bound=[+200.e-6, +200.e-6, None],
fill_in=True)
beam = picmi.Species(particle_type='electron',
name='beam',
initial_distribution=beam_distribution)
plasma = picmi.Species(particle_type='electron',
name='plasma',
initial_distribution=plasma_distribution)
sim = picmi.Simulation(solver=solver,
max_steps=1000,
verbose=1,
warpx_plot_int=2,
warpx_current_deposition_algo=3,
warpx_charge_deposition_algo=0,
warpx_field_gathering_algo=0,
warpx_particle_pusher_algo=0)
sim.add_species(beam,
############ PLASMA #############
#################################
elec_dist = picmi.UniformDistribution(
density=plasma_density,
rms_velocity=[elec_rms_velocity] * 3,
directed_velocity=[elec_rms_velocity, 0., 0.])
ion_dist = picmi.UniformDistribution(
density=plasma_density,
rms_velocity=[ion_rms_velocity] * 3,
)
electrons = picmi.Species(
particle_type='electron',
name='electron',
warpx_do_not_deposit=1,
initial_distribution=elec_dist,
)
ions = picmi.Species(particle_type='H',
name='ion',
charge='q_e',
mass="5*m_e",
warpx_do_not_deposit=1,
initial_distribution=ion_dist)
#################################
########## COLLISIONS ###########
#################################
collision1 = picmi.CoulombCollisions(name='collisions1',
species=[electrons, ions],
##########################
# physics components
##########################
uniform_plasma_elec = picmi.UniformDistribution(
density=1e23, # number of electrons per m^3
lower_bound=[-1e-5, -1e-5, -149e-6],
upper_bound=[1e-5, 1e-5, -129e-6],
directed_velocity=[0., 0., 2000. * picmi.constants.c
] # uth the std of the (unitless) momentum
)
electrons = picmi.Species(particle_type='electron',
name='electrons',
initial_distribution=uniform_plasma_elec,
warpx_save_particles_at_xhi=1,
warpx_save_particles_at_eb=1)
##########################
# numerics components
##########################
grid = picmi.Cartesian3DGrid(
number_of_cells=[nx, ny, nz],
lower_bound=[xmin, ymin, zmin],
upper_bound=[xmax, ymax, zmax],
lower_boundary_conditions=['none', 'none', 'none'],
upper_boundary_conditions=['none', 'none', 'none'],
lower_boundary_conditions_particles=['open', 'open', 'open'],
upper_boundary_conditions_particles=['open', 'open', 'open'],
grid=grid, cfl=1., stencil_order=[em_order, em_order, em_order])
electron_beam = picmi.GaussianBunchDistribution(
n_physical_particles=total_charge / constants.q_e,
rms_bunch_size=[beam_rms_size, beam_rms_size, beam_rms_size],
velocity_divergence=[
electron_beam_divergence, electron_beam_divergence,
electron_beam_divergence
])
proton_beam = picmi.GaussianBunchDistribution(
n_physical_particles=total_charge / constants.q_e,
rms_bunch_size=[beam_rms_size, beam_rms_size, beam_rms_size])
electrons = picmi.Species(particle_type='electron',
name='electrons',
initial_distribution=electron_beam)
protons = picmi.Species(particle_type='proton',
name='protons',
initial_distribution=proton_beam)
field_diag1 = picmi.FieldDiagnostic(
name='diag1',
grid=grid,
period=10,
data_list=args.fields_to_plot,
warpx_format=args.diagformat,
write_dir='.',
warpx_file_prefix='Python_gaussian_beam_plt')
part_diag1 = picmi.ParticleDiagnostic(name='diag1',
upper_boundary_conditions_particles=[
'absorbing', 'absorbing', 'absorbing'
])
# Particles
vel_z = 0.5 * c
multiparticles_distribution = picmi.ParticleListDistribution(x=[0.05, 0.],
y=[0., 0.04],
z=[0.05, 0.05],
ux=[0., 0.],
uy=[0., 0.],
uz=[vel_z, vel_z],
weight=[1., 1.])
electrons = picmi.Species(particle_type='electron',
name='electrons',
initial_distribution=multiparticles_distribution)
# Plasma lenses
plasma_lenses = picmi.PlasmaLens(
period=0.5,
starts=[0.1, 0.11, 0.12, 0.13],
lengths=[0.1, 0.11, 0.12, 0.13],
strengths_E=[600000., 800000., 600000., 200000.],
strengths_B=[0.0, 0.0, 0.0, 0.0])
# Electromagnetic solver
solver = picmi.ElectromagneticSolver(grid=grid, method='Yee', cfl=0.7)
# Diagnostics
part_diag1 = picmi.ParticleDiagnostic(
upper_boundary_conditions_particles = ['absorbing', 'periodic'],
moving_window_velocity = None,
warpx_max_grid_size = 32
)
solver = picmi.ElectrostaticSolver(
grid=grid, method='Multigrid', required_precision=1e-6,
warpx_self_fields_verbosity=0
)
##########################
# physics components
##########################
electrons = picmi.Species(
particle_type='electron', name='electrons'
)
##########################
# diagnostics
##########################
field_diag = picmi.FieldDiagnostic(
name = 'diag1',
grid = grid,
period = 10,
data_list = ['phi'],
write_dir = '.',
warpx_file_prefix = f'Python_particle_attr_access_plt_{color}'
)
# Particles: plasma electrons
plasma_density = 2e23
plasma_xmin = -20e-06
plasma_ymin = None
plasma_zmin = 10e-06
plasma_xmax = 20e-06
plasma_ymax = None
plasma_zmax = None
uniform_distribution = picmi.UniformDistribution(
density=plasma_density,
lower_bound=[plasma_xmin, plasma_ymin, plasma_zmin],
upper_bound=[plasma_xmax, plasma_ymax, plasma_zmax],
fill_in=True)
electrons = picmi.Species(particle_type='electron',
name='electrons',
initial_distribution=uniform_distribution)
# Particles: beam electrons
q_tot = 1e-12
x_m = 0.
y_m = 0.
z_m = -28e-06
x_rms = 0.5e-06
y_rms = 0.5e-06
z_rms = 0.5e-06
ux_m = 0.
uy_m = 0.
uz_m = 500.
ux_th = 2.
uy_th = 2.
##########################
# physics components
##########################
uniform_plasma_elec = picmi.UniformDistribution(
density = 1e15, # number of electrons per m^3
lower_bound = [-1e-5, -1e-5, -125e-6],
upper_bound = [1e-5, 1e-5, -120e-6],
directed_velocity = [0., 0., 5e6] # uth the std of the (unitless) momentum
)
electrons = picmi.Species(
particle_type='electron', name='electrons',
initial_distribution=uniform_plasma_elec,
warpx_save_particles_at_zhi=1,
warpx_save_particles_at_zlo=1,
warpx_reflection_model_zhi="0.5"
)
##########################
# diagnostics
##########################
field_diag = picmi.ParticleDiagnostic(
species=electrons,
name = 'diag1',
data_list=['previous_positions'],
period = 10,
write_dir = '.',
warpx_file_prefix = 'Python_particle_reflection_plt'
)
##########################
# physics components
##########################
uniform_plasma_elec = picmi.UniformDistribution(
density = 1e15,
upper_bound = [None] * 3,
rms_velocity = [np.sqrt(constants.kb * 1e3 / constants.m_e)] * 3,
directed_velocity = [0.] * 3
)
electrons = picmi.Species(
particle_type='electron', name='electrons',
initial_distribution=uniform_plasma_elec,
warpx_save_previous_position=True
)
##########################
# diagnostics
##########################
field_diag = picmi.ParticleDiagnostic(
species=electrons,
name = 'diag1',
data_list=['previous_positions'],
period = 10,
write_dir = '.',
warpx_file_prefix = 'Python_prev_positions_plt'
)
def setup_run(self):
"""Setup simulation components."""
#######################################################################
# Set geometry and boundary conditions #
#######################################################################
self.grid = picmi.Cartesian1DGrid(
number_of_cells=[self.nz],
warpx_max_grid_size=128,
lower_bound=[0],
upper_bound=[self.gap],
lower_boundary_conditions=['dirichlet'],
upper_boundary_conditions=['dirichlet'],
lower_boundary_conditions_particles=['absorbing'],
upper_boundary_conditions_particles=['absorbing'],
warpx_potential_hi_z=self.voltage,
)
#######################################################################
# Field solver #
#######################################################################
self.solver = picmi.ElectrostaticSolver(grid=self.grid,
method='Multigrid',
required_precision=1e-12,
warpx_self_fields_verbosity=0)
#######################################################################
# Particle types setup #
#######################################################################
self.electrons = picmi.Species(
particle_type='electron',
name='electrons',
initial_distribution=picmi.UniformDistribution(
density=self.plasma_density,
rms_velocity=[
np.sqrt(constants.kb * self.elec_temp / constants.m_e)
] * 3,
))
self.ions = picmi.Species(
particle_type='He',
name='he_ions',
charge='q_e',
mass=self.m_ion,
initial_distribution=picmi.UniformDistribution(
density=self.plasma_density,
rms_velocity=[
np.sqrt(constants.kb * self.gas_temp / self.m_ion)
] * 3,
))
#######################################################################
# Collision initialization #
#######################################################################
cross_sec_direc = '../../../../warpx-data/MCC_cross_sections/He/'
mcc_electrons = picmi.MCCCollisions(
name='coll_elec',
species=self.electrons,
background_density=self.gas_density,
background_temperature=self.gas_temp,
background_mass=self.ions.mass,
scattering_processes={
'elastic': {
'cross_section':
cross_sec_direc + 'electron_scattering.dat'
},
'excitation1': {
'cross_section': cross_sec_direc + 'excitation_1.dat',
'energy': 19.82
},
'excitation2': {
'cross_section': cross_sec_direc + 'excitation_2.dat',
'energy': 20.61
},
'ionization': {
'cross_section': cross_sec_direc + 'ionization.dat',
'energy': 24.55,
'species': self.ions
},
})
mcc_ions = picmi.MCCCollisions(
name='coll_ion',
species=self.ions,
background_density=self.gas_density,
background_temperature=self.gas_temp,
scattering_processes={
'elastic': {
'cross_section': cross_sec_direc + 'ion_scattering.dat'
},
'back': {
'cross_section': cross_sec_direc + 'ion_back_scatter.dat'
},
# 'charge_exchange' : {
# 'cross_section' : cross_sec_direc+'charge_exchange.dat'
# }
})
#######################################################################
# Initialize simulation #
#######################################################################
self.sim = picmi.Simulation(
solver=self.solver,
time_step_size=self.dt,
max_steps=self.max_steps,
warpx_collisions=[mcc_electrons, mcc_ions],
warpx_load_balance_intervals=self.max_steps // 5000,
verbose=self.test)
self.sim.add_species(self.electrons,
layout=picmi.GriddedLayout(
n_macroparticle_per_cell=[self.seed_nppc],
grid=self.grid))
self.sim.add_species(self.ions,
layout=picmi.GriddedLayout(
n_macroparticle_per_cell=[self.seed_nppc],
grid=self.grid))
#######################################################################
# Add diagnostics for the CI test to be happy #
#######################################################################
field_diag = picmi.FieldDiagnostic(
name='diag1',
grid=self.grid,
period=0,
data_list=['rho_electrons', 'rho_he_ions'],
write_dir='.',
warpx_file_prefix='Python_background_mcc_1d_plt')
self.sim.add_diagnostic(field_diag)
