TD_frac updates and consistency

armi/materials/material.py

@@ -15,13 +15,7 @@
 """
 Base Material classes.
 
-All temperatures are in K, but Tc can be specified and the functions will convert for you.
-
-.. warning:: ARMI uses these objects for all material properties. Under the hood,
-     A system called MAT_PROPS is in charge of several material properties. It
-     is a more industrial-strength material property system that is currently
-     a TerraPower proprietary system. You will see references to it in this module.
-
+Most temperatures may be specified in either K or C and the functions will convert for you.
 """
 # pylint: disable=unused-argument
 import copy
@@ -43,6 +37,26 @@
 class Material:
     """
     A material is made up of elements or isotopes. It has bulk properties like mass density.
+
+    Attributes
+    ----------
+    parent : Component
+        The component to which this material belongs
+    massFrac : dict
+        Mass fractions for all nuclides in the material keyed on the nuclide symbols
+    refDens : float
+        A reference density used by some materials, for instance `SimpleSolid`s,
+        during thermal expansion
+    theoreticalDensityFrac : float
+        Fraction of the material's density in reality, which is commonly different
+        from 1.0 in solid materials due to the manufacturing process.
+        Can often be set from the blueprints input via the TD_frac material modification.
+        For programmatic setting, use `adjustTD()`.
+
+    Notes
+    -----
+    Specific material classes may have many more attributes specific to the implementation
+    for that material.
     """
 
     DATA_SOURCE = "ARMI"
@@ -72,7 +86,7 @@ def __init__(self):
         self.parent = None
         self.massFrac = {}
         self.refDens = 0.0
-        self.theoreticalDensityFrac = 0.0
+        self.theoreticalDensityFrac = 1.0
         self.cached = {}
         self._backupCache = None
 
@@ -669,6 +683,15 @@ def heatCapacity(self, Tk=None, Tc=None):
             f"Material {type(self).__name__} does not implement heatCapacity"
         )
 
+    def getTD(self):
+        """Get the fraction of theoretical density for this material."""
+        return self.theoreticalDensityFrac
+
+    def adjustTD(self, val):
+        """Set or change the fraction of theoretical density for this material."""
+        self.theoreticalDensityFrac = val
+        self.clearCache()
+
 
 class Fluid(Material):
     """A material that fills its container. Could also be a gas."""
@@ -782,6 +805,13 @@ def linearExpansionPercent(self, Tk: float = None, Tc: float = None) -> float:
     def density3(self, Tk: float = None, Tc: float = None) -> float:
         return 0.0
 
+    def density(self, Tk: float = None, Tc: float = None) -> float:
+        """
+        The same method as the parent class, but with the ability to apply a
+        non-unity theoretical density.
+        """
+        return Material.density(self, Tk=Tk, Tc=Tc) * self.getTD()
+
 
 class FuelMaterial(Material):
     """

armi/materials/mox.py

@@ -66,8 +66,6 @@ def applyInputParams(
                     label="Zero theoretical density",
                 )
             self.adjustTD(td)
-        else:
-            self.adjustTD(1.00)  # default to fully dense.
 
         if mass_frac_PU02 is not None:
             self.setMassFracPuO2(mass_frac_PU02)

armi/materials/tests/test_materials.py

@@ -55,6 +55,16 @@ def test_getChildren(self):
     def test_getChildrenWithFlags(self):
         self.assertEqual(len(self.mat.getChildrenWithFlags("anything")), 0)
 
+    def test_TD(self):
+        self.assertEqual(self.mat.getTD(), self.mat.theoreticalDensityFrac)
+
+        self.mat.clearCache()
+        self.mat._setCache("dummy", 666)
+        self.assertEqual(self.mat.cached, {"dummy": 666})
+        self.mat.adjustTD(0.5)
+        self.assertEqual(0.5, self.mat.theoreticalDensityFrac)
+        self.assertEqual(self.mat.cached, {})
+
     def test_duplicate(self):
         mat = self.mat.duplicate()
 
@@ -643,11 +653,6 @@ def test_duplicate(self):
     def test_propertyValidTemperature(self):
         self.assertGreater(len(self.mat.propertyValidTemperature), 0)
 
-    def test_adjustTD(self):
-        self.assertEqual(self.mat.theoreticalDensityFrac, 1.0)
-        self.mat.adjustTD(0.123)
-        self.assertEqual(self.mat.theoreticalDensityFrac, 0.123)
-
 
 class Thorium_TestCase(_Material_Test, unittest.TestCase):
     MAT_CLASS = materials.Thorium
@@ -695,6 +700,11 @@ def test_density(self):
         accuracy = 4
         self.assertAlmostEqual(cur, ref, accuracy)
 
+        # make sure that material modifications are correctly applied
+        self.mat.applyInputParams(TD_frac=0.1)
+        cur = self.mat.density3(Tc=25)
+        self.assertAlmostEqual(cur, ref * 0.1, accuracy)
+
     def test_linearExpansion(self):
         cur = self.mat.linearExpansion(400)
         ref = 9.67e-6

armi/materials/tests/test_uraniumOxide.py

@@ -0,0 +1,50 @@
+# Copyright 2023 TerraPower, LLC
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+"""
+Tests for Uranium Oxide.
+
+Note that more tests for UO2 are in tests/test_materials.py
+"""
+
+import unittest
+
+from armi.materials.uraniumOxide import UO2
+from armi.materials.tests.test_materials import _Material_Test
+
+
+class UraniumOxide_TestCase(_Material_Test, unittest.TestCase):
+    MAT_CLASS = UO2
+
+    def setUp(self):
+        _Material_Test.setUp(self)
+
+    def test_applyInputParams(self):
+        UO2_TD = UO2()
+        original = UO2_TD.density3(500)
+        UO2_TD.applyInputParams(TD_frac=0.1)
+        new = UO2_TD.density3(500)
+        ratio = new / original
+        self.assertAlmostEqual(ratio, 0.1)
+
+        UO2_TD = UO2()
+        original = UO2_TD.density(500)
+        UO2_TD.applyInputParams(TD_frac=0.1)
+        new = UO2_TD.density(500)
+        ratio = new / original
+        self.assertAlmostEqual(ratio, 0.1)
+
+
+if __name__ == "__main__":
+    unittest.main()

armi/materials/thoriumOxide.py

@@ -23,25 +23,18 @@
 from armi import runLog
 from armi.materials.material import FuelMaterial
 from armi.utils.units import getTk
+from armi.materials.material import Material, FuelMaterial, SimpleSolid
 
 
-class ThoriumOxide(FuelMaterial):
+class ThoriumOxide(FuelMaterial, SimpleSolid):
     name = "ThO2"
     propertyValidTemperature = {"linear expansion": ((298, 1223), "K")}
 
     def __init__(self):
-        FuelMaterial.__init__(self)
-        self.theoreticalDensityFrac = 1.0
-        self.adjustTD(self.theoreticalDensityFrac)
+        Material.__init__(self)
+        self.refDens = 10.00
 
-    def adjustTD(self, val):
-        self.theoreticalDensityFrac = val
-        self.refDens = 10.00 * val
-
-    def getTD(self):
-        return self.theoreticalDensityFrac
-
-    def applyInputParams(self, TD_frac, *args, **kwargs):
+    def applyInputParams(self, TD_frac=None, *args, **kwargs):
         if TD_frac is not None:
             if TD_frac > 1.0:
                 runLog.warning(
@@ -105,6 +98,9 @@ def meltingPoint(self):
         r"""melting point in K from IAEA TE 1450"""
         return 3643.0
 
+    def density3(self, Tk=None, Tc=None):
+        return Material.density3(self, Tk, Tc) * self.getTD()
+
 
 class ThO2(ThoriumOxide):
     """Another name for ThoriumOxide."""

armi/materials/uraniumOxide.py

@@ -68,8 +68,6 @@ class UraniumOxide(material.FuelMaterial, material.SimpleSolid):
         "heat capacity": "ORNL/TM-2000/351",
     }
 
-    theoreticalDensityFrac = 1.0  # Default value
-
     thermalScatteringLaws = (
         tsl.byNbAndCompound[nb.byName["U"], tsl.UO2],
         tsl.byNbAndCompound[nb.byName["O"], tsl.UO2],
@@ -105,15 +103,8 @@ class UraniumOxide(material.FuelMaterial, material.SimpleSolid):
 
     def __init__(self):
         material.FuelMaterial.__init__(self)
-        self.theoreticalDensityFrac = 1.0
         self.refDens = self.density3(Tk=self.refTempK)
 
-    def adjustTD(self, val: float) -> None:
-        self.theoreticalDensityFrac = val
-
-    def getTD(self) -> float:
-        return self.theoreticalDensityFrac
-
     def applyInputParams(
         self, U235_wt_frac: float = None, TD_frac: float = None, *args, **kwargs
     ) -> None:
@@ -136,8 +127,6 @@ def applyInputParams(
                     label="Zero theoretical density",
                 )
             self.adjustTD(td)
-        else:
-            self.adjustTD(1.00)  # default to fully dense.
 
         material.FuelMaterial.applyInputParams(self, *args, **kwargs)
 

doc/release/0.2.rst

@@ -43,6 +43,7 @@ Bug fixes
 #. Fixed a bug where the material namespace order for test_axialExpansionChanger.py was persisting beyond the tests. (`PR#1046 https://github.com/terrapower/armi/pull/1046`_)
 #. A bug was fixed in `PR#1022 <https://github.com/terrapower/armi/pull/1022>`_ where the gaseous fission products were not being removed from the core directly, but instead the fission yields within the lumped fission products were being adjusted.
 #. Fixed a bug where non-fuel depletable components were not being initialized with all nuclides with the ``explicitFissionProducts`` model (`PR#1067 https://github.com/terrapower/armi/pull/1067`_)
+#. Fixed a bug in which the TD_frac material modification on UraniumOxide and MOX materials was not being applied correctly in density calculations
 #. Bug fix to ensure consistency between cross section group manager and lattice physics interface for tight coupling. (`PR#1118 <https://github.com/terrapower/armi/pull/1118>`_)
 #. Bug fix to update pseudo density to physical density in densityTimesHeatCapacity materials method. (`PR#1129 <https://github.com/terrapower/armi/pull/1129>`_)