Add single assembly example model

examples/assembly/assembly.py

@@ -0,0 +1,140 @@
+"""
+This script builds a single PWR assembly and is a slightly more advanced
+demonstration of model building using Python. The creation of two universes for
+fuel pins and guide tube pins has been separated into functions, and then the
+overall model is built by an `assembly` function. This script also demonstrates
+the use of the `Model` class, which provides some extra convenience over using
+`Geometry`, `Materials`, and `Settings` classes directly. Finally, the script
+takes two command-line flags that indicate whether to build and/or run the
+model.
+
+"""
+
+import argparse
+from math import log10
+
+import numpy as np
+import openmc
+
+# Define surfaces
+fuel_or = openmc.ZCylinder(r=0.39218, name='Fuel OR')
+clad_or = openmc.ZCylinder(r=0.45720, name='Clad OR')
+
+# Define materials
+fuel = openmc.Material(name='Fuel')
+fuel.set_density('g/cm3', 10.29769)
+fuel.add_nuclide('U234', 4.4843e-6)
+fuel.add_nuclide('U235', 5.5815e-4)
+fuel.add_nuclide('U238', 2.2408e-2)
+fuel.add_nuclide('O16', 4.5829e-2)
+
+clad = openmc.Material(name='Cladding')
+clad.set_density('g/cm3', 6.55)
+clad.add_nuclide('Zr90', 2.1827e-2)
+clad.add_nuclide('Zr91', 4.7600e-3)
+clad.add_nuclide('Zr92', 7.2758e-3)
+clad.add_nuclide('Zr94', 7.3734e-3)
+clad.add_nuclide('Zr96', 1.1879e-3)
+
+hot_water = openmc.Material(name='Hot borated water')
+hot_water.set_density('g/cm3', 0.740582)
+hot_water.add_nuclide('H1', 4.9457e-2)
+hot_water.add_nuclide('O16', 2.4672e-2)
+hot_water.add_nuclide('B10', 8.0042e-6)
+hot_water.add_nuclide('B11', 3.2218e-5)
+hot_water.add_s_alpha_beta('c_H_in_H2O')
+
+
+def fuel_pin():
+    """Returns a fuel pin universe."""
+
+    fuel_cell = openmc.Cell(fill=fuel, region=-fuel_or)
+    clad_cell = openmc.Cell(fill=clad, region=+fuel_or & -clad_or)
+    hot_water_cell = openmc.Cell(fill=hot_water, region=+clad_or)
+
+    univ = openmc.Universe(name='Fuel Pin')
+    univ.add_cells([fuel_cell, clad_cell, hot_water_cell])
+    return univ
+
+
+def guide_tube_pin():
+    """Returns a control rode guide tube pin universe"""
+
+    gt_inner_cell = openmc.Cell(fill=hot_water, region=-fuel_or)
+    gt_clad_cell = openmc.Cell(fill=clad, region=+fuel_or & -clad_or)
+    gt_outer_cell = openmc.Cell(fill=hot_water, region=+clad_or)
+
+    univ = openmc.Universe(name='Guide Tube')
+    univ.add_cells([gt_inner_cell, gt_clad_cell, gt_outer_cell])
+    return univ
+
+
+def assembly_model():
+    """Returns a single PWR fuel assembly."""
+
+    model = openmc.model.Model()
+
+    # Create fuel assembly Lattice
+    pitch = 21.42
+    assembly = openmc.RectLattice(name='Fuel Assembly')
+    assembly.pitch = (pitch/17, pitch/17)
+    assembly.lower_left = (-pitch/2, -pitch/2)
+
+    # Create array indices for guide tube locations in lattice
+    gt_pos = np.array([
+                  [2, 5],   [2, 8],   [2, 11],
+             [3, 3],                        [3, 13],
+        [5, 2],   [5, 5],   [5, 8],   [5, 11],    [5, 14],
+        [8, 2],   [8, 5],   [8, 8],   [8, 11],    [8, 14],
+        [11, 2],  [11, 5],  [11, 8],  [11, 11],   [11, 14],
+             [13, 3],                       [13, 13],
+                  [14, 5],  [14, 8],  [14, 11]
+    ])
+
+    # Create 17x17 array of universes. First we create a 17x17 array all filled
+    # with the fuel pin universe. Then, we replace the guide tube positions with
+    # the guide tube pin universe (note the use of numpy fancy indexing to
+    # achieve this).
+    assembly.universes = np.full((17, 17), fuel_pin())
+    assembly.universes[gt_pos[:, 0], gt_pos[:, 1]] = guide_tube_pin()
+
+    # Create outer boundary of the geometry to surround the lattice
+    outer_boundary = openmc.model.rectangular_prism(
+        pitch, pitch, boundary_type='reflective')
+
+    # Create a cell filled with the lattice
+    main_cell = openmc.Cell(fill=assembly, region=outer_boundary)
+
+    # Finally, create geometry by giving a list of cells filling the root
+    # universe
+    model.geometry = openmc.Geometry([main_cell])
+
+    model.settings.batches = 150
+    model.settings.inactive = 50
+    model.settings.particles = 1000
+    model.settings.source = openmc.Source(space=openmc.stats.Box(
+        (-pitch/2, -pitch/2, -1),
+        (pitch/2, pitch/2, 1),
+        only_fissionable=True
+    ))
+
+    # NOTE: We never actually created a Materials object. When you export/run
+    # using the Model object, if no materials were assigned it will look through
+    # the Geometry object and automatically export any materials that are
+    # necessary to build the model.
+    return model
+
+
+if __name__ == '__main__':
+    # Set up command-line arguments for generating/running the model
+    parser = argparse.ArgumentParser()
+    parser.add_argument('--generate', action='store_true')
+    parser.add_argument('--run', action='store_true')
+    args = parser.parse_args()
+
+    if args.generate or args.run:
+        model = assembly_model()
+        if args.generate:
+            model.export_to_xml()
+        if args.run:
+            model.run()