def test_1D_particle_source_region(self):
"""Set up a one-dimensional source region and display it.
"""
fncName = '(' + __file__ + ') ' + sys._getframe(
).f_code.co_name + '():\n'
print('\ntest: ', fncName, '(' + __file__ + ')')
## Set control variables
ctrl = DTcontrol_C()
ctrl.title = "test_ParticleGeneration.py:test_1D_particle_source_region"
ctrl.author = "tph"
ctrl.timeloop_count = 0
ctrl.time = 0.0
ctrl.dt = 1.0e-6
ctrl.n_timesteps = 1
ctrl.write_trajectory_files = False
pin = self.pin
pin.coordinate_system = 'cartesian_x'
pin.force_components = [
'x',
]
### Particle input
## Define electron species
charge = -1.0 * MyPlasmaUnits_C.elem_charge
mass = 1.0 * MyPlasmaUnits_C.electron_mass
dynamics = 'explicit'
electrons_S = ParticleSpecies_C('electrons', charge, mass, dynamics)
# Add the electrons to particle input
pin.particle_species = (electrons_S, )
## Make the particle storage array for all species.
particle_P = Particle_C(pin, print_flag=True)
## Give the name of the .py file containing special particle data (lists of
# particles, boundary conditions, source regions, etc.)
userParticlesModuleName = "UserParticles_1D"
# Import this module
userParticlesModule = im_m.import_module(userParticlesModuleName)
# particle_P.user_particles_module_name = userParticlesModuleName
particle_P.user_particles_class = userParticlesClass = userParticlesModule.UserParticleDistributions_C
### Mesh input for a 1D mesh
# Specify the mesh parameters
umi1D = UserMeshInput_C()
umi1D.pmin = df_m.Point(-10.0)
umi1D.pmax = df_m.Point(10.0)
umi1D.cells_on_side = (20, ) # Need the comma to indicate a tuple
### Create the 1D particle mesh and add to the Particle_C object
pmesh1D = UserMesh_C(umi1D,
compute_dictionaries=True,
compute_cpp_arrays=False,
compute_tree=True,
plot_flag=False)
particle_P.pmesh_M = pmesh1D
### Input for particle sources
# For each source:
# a. Define the source region
# b. Provide a particle-generating function
# c. Provide the species name and physical source parameters
# Create numpy storage needed below
driftVelocity = np_m.empty(particle_P.particle_dimension,
dtype=particle_P.precision)
## 1. Hot electron source on left side of the mesh
# a. Provide the species name and physical parameters
# for this source
speciesName = 'electrons'
# Check that this species has been defined
if speciesName in particle_P.species_names:
charge = particle_P.charge[speciesName]
mass = particle_P.mass[speciesName]
else:
print("The species", speciesName, "has not been defined")
sys.exit()
sourceDistributionType = 'functional'
# Compute a physical number-density creation rate for this source region
# The value should always be positive
chargeDensityRate = -1.0
# The timestep interval between calls to the creation function
timeStepInterval = 1
# Get number-density added per invocation
numberDensity = chargeDensityRate * timeStepInterval * ctrl.dt / charge
# Check for positivity
if numberDensity < 0:
print("Check number density for species", speciesName,
"is negative. Should be positive")
sys.exit()
# Compute a value for thermalSpeed from the temperature in eV
temperature_eV = 2.0
temp_joule = temperature_eV * MyPlasmaUnits_C.elem_charge
thermalSpeed = np_m.sqrt(2.0 * temp_joule / mass)
velocity_coordinate_system = 'x_y_z' # This sets the interpretation of the
# following values
# Set a drift velocity
vdrift_1 = 1.0
vdrift_2 = 2.0
vdrift_3 = 3.0
# driftVelocity = (vdrift_1, vdrift_2, vdrift_3)
driftVelocity[0] = vdrift_1
# The particle storage arrays have only a v[0] velocity component
# driftVelocity[1] = vdrift_2
# driftVelocity[2] = vdrift_3
# Set desired particles-per-cell
numberPerCell = 1
# Collect the parameters for this source in a dictionary
hotElectronParams = {
'species_name': speciesName,
'source_distribution_type': sourceDistributionType,
'number_density': numberDensity,
'thermal_speed': thermalSpeed,
'velocity_coordinate_system': velocity_coordinate_system,
'drift_velocity': driftVelocity,
'timestep_interval': timeStepInterval,
'number_per_cell': numberPerCell
}
# b. Name the particle-creation function.
maxwellianGenerator = particle_P.create_maxwellian_particles
# c. Source-region geometry
xmin = -9.0
xmax = -4.0
hotElectronsRegion = RectangularRegion_C(pmesh1D, xmin, xmax)
## 2. Background electrons over the whole mesh
## Specify one or more species to be generated in the 2nd region.
# a. Provide the species name and physical parameters for this source
# Note that this is the same species as in ## 1. above. It's not necessary
# for each source region to have a different species name.
speciesName = 'electrons'
# Check that this species has been defined above
if speciesName in particle_P.species_names:
charge = particle_P.charge[speciesName]
mass = particle_P.mass[speciesName]
else:
print("The species", speciesName, "has not been defined")
sys.exit()
sourceDistributionType = 'functional'
# Compute a value for numberDensity, the physical number-density
# creation rate for this source region.
# The value should always be positive.
chargeDensityRate = -0.1
# The timestep interval between calls to the creation function
timeStepInterval = 1
# Get charge-density per invocation
numberDensity = chargeDensityRate * timeStepInterval * ctrl.dt / charge
# Check for positivity
if numberDensity < 0:
print("Check number density for species", speciesName,
"is negative. Should be positive")
sys.exit()
# Compute a value for thermalSpeed
temperature_eV = 2.0
temp_joule = temperature_eV * MyPlasmaUnits_C.elem_charge
thermalSpeed = np_m.sqrt(2.0 * temp_joule / mass)
velocity_coordinate_system = 'x_y_z' # This sets the interpretation of the
# following values
# Set a drift velocity
vdrift_1 = 0.5
vdrift_2 = 1.5
vdrift_3 = 2.5
# driftVelocity = (vdrift_1, vdrift_2, vdrift_3)
# The particle storage arrays have only a v[0] velocity component
driftVelocity[0] = vdrift_1
# Set desired particles-per-cell
numberPerCell = 10
# Collect the parameters for this source in a dictionary
backgroundElectronParams = {
'species_name': speciesName,
'source_distribution_type': sourceDistributionType,
'number_density': numberDensity,
'thermal_speed': thermalSpeed,
'velocity_coordinate_system': velocity_coordinate_system,
'drift_velocity': driftVelocity,
'timestep_interval': timeStepInterval,
'number_per_cell': numberPerCell
}
# b. Name the first function that will generate particles in the above region:
# Just use same maxwellianGenerator function as above.
# c. Source geometry: in this case, it's the whole mesh:
wholeMesh = WholeMesh_C(pmesh1D)
## Put all the particle source data into a dictionary
# The dictionary keys are mnemonic source names.
# The dictionary values are lists of tuples giving the
# a. the physical source parameters.
# b. particle creation function and
# c. source region
## Note: the names here are source-region names, NOT species names!
particleSourceDict = {
'hot_electron_source':
(hotElectronParams, maxwellianGenerator, hotElectronsRegion),
'background_electron_source':
(backgroundElectronParams, maxwellianGenerator, wholeMesh),
}
particle_P.particle_source_dict = particleSourceDict
### Create input for a particle trajectory object
# Use an input object to collect initialization data for the trajectory object
self.trajin = TrajectoryInput_C()
self.trajin.maxpoints = None # Set to None to get every point
self.trajin.extra_points = 1 # Set to 1 to make sure one boundary-crossing can be
# accommodated. Set to a larger value if there are
# multiple boundary reflections.
self.trajin.explicit_dict = {
'names': [
'x',
'ux',
],
'formats': [np_m.float32] * 2
}
## Create the trajectory object and attach it to the particle object.
# No trajectory storage is created until particles
# with TRAJECTORY_FLAG on are encountered.
p_P = particle_P
traj_T = Trajectory_C(self.trajin, ctrl, p_P.charged_species,
p_P.neutral_species, p_P.species_index, p_P.mass,
p_P.charge)
particle_P.traj_T = traj_T
## Invoke the source functions and write out the particles
### Select output for particles
ctrl.particle_output_file = "particleGeneration.h5part"
ctrl.particle_output_interval = 1
ctrl.particle_output_attributes = ('species_index', 'x', 'ux',
'weight')
# Check these values
particle_P.check_particle_output_parameters(ctrl)
particle_P.add_more_particles(ctrl)
# Dump the particle data to a file
particle_P.initialize_particle_output_file(ctrl)
# Write the particle attributes
particle_P.write_particles_to_file(ctrl)
return
def test_3_function_initialized_particles(self):
""" Test initialization of particles using a function over a region of
the mesh.
"""
fncName = '(' + __file__ + ') ' + sys._getframe(
).f_code.co_name + '():\n'
print('\ntest: ', fncName, '(' + __file__ + ')')
## Control struct
ctrl = DTcontrol_C()
## Mesh input
mi2d_UMI = UserMeshInput_C()
# Replace with TUPLES since we're at toplevel
mi2d_UMI.pmin = df_m.Point(-10.0, -10.0)
mi2d_UMI.pmax = df_m.Point(10.0, 10.0)
mi2d_UMI.cells_on_side = (2, 2)
mi2d_UMI.diagonal = 'left'
## Create a 2D particle mesh, since we're going to initialize particles
## on a region of a mesh.
# UserMesh_y_Fields_FE_XYZ_Module can make the mesh from the above input.
plotFlag = False
plotTitle = os.path.basename(
__file__) + ": " + sys._getframe().f_code.co_name + ": mesh"
pmesh2d_UM = UserMesh_C(mi2d_UMI,
compute_dictionaries=True,
compute_cpp_arrays=False,
compute_tree=True,
plot_flag=plotFlag,
plot_title=plotTitle)
p_P = self.particle_P
userParticlesClass = p_P.user_particles_class
## 1. Initial hot electrons on bottom-left side of the mesh
# a. Provide the species name and physical parameters
# for this particle-initialization
speciesName = 'plasma_electrons'
# Check that this species has been defined
if speciesName in p_P.species_names:
charge = p_P.charge[speciesName]
mass = p_P.mass[speciesName]
else:
print("The species", speciesName, "needs to be defined.")
sys.exit()
initialDistributionType = 'function_over_region'
# Specify the initial physical number-density for this species
numberDensity = 1.0e12
# Check for positivity
if numberDensity <= 0:
print("Check number density for species", speciesName,
"is zero or negative. Should be positive")
sys.exit()
# Compute a value for thermalSpeed from the temperature in eV
temperature_eV = 2.0
temp_joule = temperature_eV * MyPlasmaUnits_C.elem_charge
thermalSpeed = np_m.sqrt(2.0 * temp_joule / mass)
# Set a drift velocity
# Set a drift velocity
vdrift_1 = 1.0
vdrift_2 = 2.0
vdrift_3 = 3.0
velocity_coordinate_system = 'x_y_z' # This sets the interpretation of the
# following values
driftVelocity = (vdrift_1, vdrift_2, vdrift_3)
# driftVelocity[:] = (1.0,)
# Set desired particles-per-cell
numberPerCell = 1000
# Collect the parameters for this initialization in a dictionary
hotElectronParams = {
'species_name': speciesName,
'initial_distribution_type': initialDistributionType,
'number_density': numberDensity,
'thermal_speed': thermalSpeed,
'velocity_coordinate_system': velocity_coordinate_system,
'drift_velocity': driftVelocity,
'number_per_cell': numberPerCell
}
# b. Name the particle-creation function.
maxwellianGenerator = p_P.create_maxwellian_particles
# c. Initialization-region geometry
xmin = -9.0
ymin = -9.0
xmax = -4.0
ymax = -4.0
# Don't use df_m in the toplevel routine, if possible
# pmin = df_m.Point(xmin, ymin)
# pmax = df_m.Point(xmax, ymax)
pmin = (xmin, ymin)
pmax = (xmax, ymax)
hotElectronsRegion_RR = RectangularRegion_C(pmesh2d_UM, pmin, pmax)
## Put all the particle-initialization data into a dictionary
# The dictionary keys are mnemonics for particle-initialization names.
# The dictionary values are lists of tuples giving the
# a. the physical initialization parameters.
# b. particle creation function and
# c. initialization region
## Note: the names here are particle-initialization names, NOT species names!
initialParticlesDict = {
'initial_hot_electrons':
(hotElectronParams, maxwellianGenerator, hotElectronsRegion_RR),
# 'initial_background_electrons': (backgroundElectronParams, maxwellianGenerator, wholeMesh),
}
# Replace the 'listed' initial particles made in Setup() with
# the 'function_initialized' initial particles created above
p_P.initial_particles_dict = initialParticlesDict
# Loop on the initialization methods in the dictionary
# For 'listed' initialization, the dictionary has entries like
# {ipName: (ipParams,)}
# For 'function_over_region' initialization, the dictionary has entries
# like
# {ipName: (ipParams, ipFunc, ipRegion_RR)}
nCreatedTotal = 0
for ipName, ipTuple in initialParticlesDict.items():
ipParams = ipTuple[0]
s = ipParams['species_name']
initialDistributionType = ipParams['initial_distribution_type']
if initialDistributionType == 'function_over_region':
print(fncName, "Initializating", ipName, "particles")
ipFunc = ipTuple[1]
ipRegion_RR = ipTuple[2]
# Invoke the creation function
step = 0
time = 0.0
neg_E_field = None
ipFunc(step, time, ipRegion_RR, ipParams, neg_E_field)
# Check the number of stored particles for each species
nCreated = ipRegion_RR.ncell * ipParams['number_per_cell']
print(fncName, "Number of particles created =", nCreated)
nCreatedTotal += nCreated
nStored = p_P.get_species_particle_count(s, print_flag=False)
self.assertEqual(
nStored,
nCreated,
msg="Number of stored particles is not correct")
# check total number of stored particles
nStored = p_P.get_total_particle_count(print_flag=False)
print(fncName, "Total number of particles created =", nCreatedTotal)
self.assertEqual(nStored,
nCreatedTotal,
msg="Total number of stored particles is not correct")
# Write out the particles to an HDF5 file
ctrl.timeloop_count = 0
ctrl.time = 0.0
# Run identifier
ctrl.title = "test_ParticleInitialization"
# Run author
ctrl.author = "tph"
### Select output for particles
ctrl.particle_output_file = "particleInitialization.h5part"
ctrl.particle_output_interval = 1
ctrl.particle_output_attributes = ('species_index', 'x', 'y', 'z',
'ux', 'uy', 'uz', 'weight')
# Check these values
p_P.check_particle_output_parameters(ctrl)
# Dump the particle data to a file
p_P.initialize_particle_output_file(ctrl)
# Write the particle attributes
p_P.write_particles_to_file(ctrl)
return