OpenMC/tests/unit_tests/test_spherical_mesh.py
Patrick Shriwise 19f121a45a
Python mesh coordinates reorder (#2730)
Co-authored-by: Ethan Peterson <eepeterson3@gmail.com>
2023-11-01 11:19:27 -06:00

208 lines
6.3 KiB
Python

from itertools import product, permutations
import openmc
import numpy as np
import pytest
geom_size = 5
@pytest.fixture()
def model():
openmc.reset_auto_ids()
water = openmc.Material(name='water')
water.add_element('H', 2.0)
water.add_element('O', 1.0)
water.set_density('g/cc', 1.0)
rpp = openmc.model.RectangularParallelepiped(*([-geom_size, geom_size] * 3),
boundary_type='vacuum')
cell = openmc.Cell(region=-rpp, fill=water)
geom = openmc.Geometry([cell])
source = openmc.IndependentSource()
source.space = openmc.stats.Point()
source.energy = openmc.stats.Discrete([10000], [1.0])
settings = openmc.Settings()
settings.particles = 2000
settings.batches = 10
settings.run_mode = 'fixed source'
# build
mesh = openmc.SphericalMesh(
phi_grid=np.linspace(0, 2*np.pi, 13),
theta_grid=np.linspace(0, np.pi, 7),
r_grid=np.linspace(0, geom_size, geom_size),
)
tally = openmc.Tally()
mesh_filter = openmc.MeshFilter(mesh)
tally.filters.append(mesh_filter)
tally.scores.append("flux")
tallies = openmc.Tallies([tally])
return openmc.Model(geometry=geom, settings=settings, tallies=tallies)
def test_origin_read_write_to_xml(run_in_tmpdir, model):
"""Tests that the origin attribute can be written and read back to XML
"""
mesh = model.tallies[0].filters[0].mesh
mesh.origin = [0.1, 0.2, 0.3]
model.tallies.export_to_xml()
# read back
new_tallies = openmc.Tallies.from_xml()
new_tally = new_tallies[0]
new_mesh = new_tally.filters[0].mesh
np.testing.assert_equal(new_mesh.origin, mesh.origin)
estimators = ('tracklength', 'collision')
# TODO: determine why this is needed for spherical mesh
# but not cylindrical mesh
offset = geom_size + 0.001
origins = set(permutations((-offset, 0, 0)))
origins |= set(permutations((offset, 0, 0)))
test_cases = product(estimators, origins)
def label(p):
if isinstance(p, tuple):
return f'origin:{p}'
if isinstance(p, str):
return f'estimator:{p}'
@pytest.mark.parametrize('estimator,origin', test_cases, ids=label)
def test_offset_mesh(run_in_tmpdir, model, estimator, origin):
"""Tests that the mesh has been moved based on tally results
"""
mesh = model.tallies[0].filters[0].mesh
model.tallies[0].estimator = estimator
# move the center of the spherical mesh
mesh.origin = origin
sp_filename = model.run()
with openmc.StatePoint(sp_filename) as sp:
tally = sp.tallies[1]
# we've translated half of the spherical mesh above the model,
# so ensure that half of the bins are populated
assert np.count_nonzero(tally.mean) == tally.mean.size / 2
# check that the half of the mesh that is outside of the geometry
# contains the zero values
mean = tally.get_reshaped_data('mean', expand_dims=True)
centroids = mesh.centroids
for ijk in mesh.indices:
i, j, k = np.array(ijk) - 1
if model.geometry.find(centroids[i, j, k]):
mean[i, j, k] == 0.0
else:
mean[i, j, k] != 0.0
# Some void geometry tests to check our radial intersection methods on
# spherical and cylindrical meshes
@pytest.fixture()
def void_coincident_geom_model():
"""A model with many geometric boundaries coincident with mesh boundaries
across many scales
"""
openmc.reset_auto_ids()
model = openmc.Model()
model.materials = openmc.Materials()
radii = [0.1, 1, 5, 50, 100, 150, 250]
spheres = [openmc.Sphere(r=ri) for ri in radii]
spheres[-1].boundary_type = 'vacuum'
regions = openmc.model.subdivide(spheres)[:-1]
cells = [openmc.Cell(region=r, fill=None) for r in regions]
geom = openmc.Geometry(cells)
model.geometry = geom
settings = openmc.Settings(run_mode='fixed source')
settings.batches = 2
settings.particles = 5000
model.settings = settings
mesh = openmc.SphericalMesh(r_grid=np.linspace(0, 250, 501))
mesh_filter = openmc.MeshFilter(mesh)
tally = openmc.Tally()
tally.scores = ['flux']
tally.filters = [mesh_filter]
model.tallies = openmc.Tallies([tally])
return model
# convenience function for checking tally results
# in the following tests
def _check_void_spherical_tally(statepoint_filename):
with openmc.StatePoint(statepoint_filename) as sp:
flux_tally = sp.tallies[1]
mesh = flux_tally.find_filter(openmc.MeshFilter).mesh
neutron_flux = flux_tally.get_reshaped_data().squeeze()
# the flux values for each bin should equal the width
# width of the mesh bins
d_r = mesh.r_grid[1] - mesh.r_grid[0]
assert neutron_flux == pytest.approx(d_r)
def test_void_geom_pnt_src(run_in_tmpdir, void_coincident_geom_model):
# add isotropic point source
src = openmc.IndependentSource()
src.space = openmc.stats.Point()
src.energy = openmc.stats.Discrete([14.06e6], [1])
void_coincident_geom_model.settings.source = src
# run model and check tally results
sp_filename = void_coincident_geom_model.run()
_check_void_spherical_tally(sp_filename)
def test_void_geom_boundary_src(run_in_tmpdir, void_coincident_geom_model):
# update source to a number of points on the outside of the sphere
# with directions pointing toward the origin
n_sources = 20
phi_vals = np.linspace(0, np.pi, n_sources)
theta_vals = np.linspace(0, 2.0*np.pi, n_sources)
bbox = void_coincident_geom_model.geometry.bounding_box
# can't source particles directly on the geometry boundary
outer_r = bbox[1][0] - 1e-08
sources = []
energy = openmc.stats.Discrete([14.06e6], [1])
for phi, theta in zip(phi_vals, theta_vals):
src = openmc.IndependentSource()
src.energy = energy
pnt = np.array([np.sin(phi)*np.cos(theta), np.sin(phi)*np.sin(theta), np.cos(phi)])
u = -pnt
src.space = openmc.stats.Point(outer_r*pnt)
src.angle = openmc.stats.Monodirectional(u)
# set source strengths so that we can still expect
# a tally value of 0.5
src.strength = 0.5/n_sources
sources.append(src)
void_coincident_geom_model.settings.source = sources
sp_filename = void_coincident_geom_model.run()
_check_void_spherical_tally(sp_filename)