Update fluid volumes after prescribed axial expansion

armi/reactor/converters/axialExpansionChanger/axialExpansionChanger.py

@@ -19,8 +19,8 @@
 from armi.reactor.converters.axialExpansionChanger.assemblyAxialLinkage import (
     AssemblyAxialLinkage,
 )
-from armi.reactor.converters.axialExpansionChanger.expansionData import ExpansionData
 from armi.reactor.converters.axialExpansionChanger.expansionData import (
+    ExpansionData,
     getSolidComponents,
 )
 from armi.reactor.flags import Flags
@@ -359,8 +359,8 @@ def axiallyExpandAssembly(self):
 
             _checkBlockHeight(b)
             # Call Component.clearCache to update the Component volume, and therefore the masses,
-            # of all solid components.
-            for c in getSolidComponents(b):
+            # of all components.
+            for c in b:
                 c.clearCache()
             # redo mesh -- functionality based on assembly.calculateZCoords()
             mesh.append(b.p.ztop)

armi/reactor/converters/tests/test_axialExpansionChanger.py

@@ -451,6 +451,10 @@ def test_noMovementACLP(self):
         .. test:: Ensure the ACLP does not move during fuel-only expansion.
             :id: T_ARMI_AXIAL_EXP_PRESC1
             :tests: R_ARMI_AXIAL_EXP_PRESC
+
+        .. test:: Ensure the component volumes are correctly updated during prescribed expansion.
+            :id: T_ARMI_AXIAL_EXP_PRESC2
+            :tests: R_ARMI_AXIAL_EXP_PRESC
         """
         # build test assembly with ACLP
         assembly = HexAssembly("testAssemblyType")
@@ -473,6 +477,9 @@ def test_noMovementACLP(self):
         aclpZTop = aclp.p.ztop
         aclpZBottom = aclp.p.zbottom
 
+        # get total assembly fluid mass pre-expansion
+        preExpAssemFluidMass = self._getTotalAssemblyFluidMass(assembly)
+
         # expand fuel
         # get fuel components
         cList = [c for b in assembly for c in b if c.hasFlags(Flags.FUEL)]
@@ -481,6 +488,9 @@ def test_noMovementACLP(self):
         chngr = AxialExpansionChanger()
         chngr.performPrescribedAxialExpansion(assembly, cList, pList, setFuel=True)
 
+        # get total assembly fluid mass post-expansion
+        postExpAssemFluidMass = self._getTotalAssemblyFluidMass(assembly)
+
         # do assertion
         self.assertEqual(
             aclpZBottom,
@@ -493,6 +503,26 @@ def test_noMovementACLP(self):
             msg="ACLP ztop has changed. It should not with fuel component only expansion!",
         )
 
+        # verify that the component volumes are correctly updated
+        for b in assembly:
+            for c in b:
+                self.assertAlmostEqual(
+                    c.getArea() * b.getHeight(),
+                    c.getVolume(),
+                    places=12,
+                )
+        # verify that the total assembly fluid mass is preserved through expansion
+        self.assertAlmostEqual(preExpAssemFluidMass, postExpAssemFluidMass, places=11)
+
+    @staticmethod
+    def _getTotalAssemblyFluidMass(assembly) -> float:
+        totalAssemblyFluidMass = 0.0
+        for b in assembly:
+            for c in b:
+                if isinstance(c.material, materials.material.Fluid):
+                    totalAssemblyFluidMass += c.getMass()
+        return totalAssemblyFluidMass
+
     def test_reset(self):
         self.obj.setAssembly(self.a)
         self.obj.reset()

doc/release/0.4.rst

@@ -35,6 +35,7 @@ Bug Fixes
 #. Fixed ``PermissionError`` when using ``syncDbAfterWrite``. (`PR#1857 <https://github.com/terrapower/armi/pull/1857>`_)
 #. Fixed ``MpiDirectoryChanger``. (`PR#1853 <https://github.com/terrapower/armi/pull/1853>`_)
 #. Changed data type of ``thKernel`` setting from ``bool`` to ``str`` in ``ThermalHydraulicsPlugin``. (`PR#1855 <https://github.com/terrapower/armi/pull/1855>`_)
+#. Update height of fluid components after axial expansion (`PR#1828 <https://github.com/terrapower/armi/pull/1828>`_)
 #. TBD
 
 Quality Work