Remove circular function calls.

armi/reactor/components/component.py

@@ -669,43 +669,19 @@ def setTemperature(self, temperatureInC):
         self.changeNDensByFactor(f)
         self.clearLinkedCache()
 
-    def setPuFrac(self, prevPuFrac):
-        r"""
-        Adjust puFrac of this component.
-
-        This will cause effective expansion or contraction of solid components similar to thermal 
-        expansion but at a constant temperature. If the thermal expansion coefficient is dependent 
-        on composition (like puFrac), then changing the puFrac at a constant temperature will 
-        effectively expand/contract the material. When this happens, number densities need to be 
-        adjusted to conserve mass.
-
-        Since some composites have multiple materials in them that thermally expand differently,
-        the axial dimension is generally left unchanged. Hence, this a 2-D thermal expansion.
-
-        Number density change is proportional to mass density change :math:`\frac{d\rho}{\rho}`.
-        A multiplicative factor :math:`f_N` to apply to number densities when going from T to T'
-        is as follows:
-
-        .. math::
-
-            N^{\prime} = N \cdot f_N \\
-            \frac{dN}{N} = f_N - 1
-
-        Since :math:`\frac{dN}{N} \sim\frac{d\rho}{\rho}`, we have:
-
-        .. math::
-
-            f_N  = \frac{d\rho}{\rho} + 1 = \frac{\rho^{\prime}}{\rho}
-
+    def changeNDensByFactor(self, factor):
         """
-        prevMaterial = self.material.__class__()
-        prevMaterial.puFrac = prevPuFrac
-        dLLprev = prevMaterial.linearExpansionPercent(Tc=self.temperatureInC) / 100.0
-        dLLnew = self.material.linearExpansionPercent(Tc=self.temperatureInC) / 100.0
-        expansionRatio = (1.0 + dLLnew) / (1.0 + dLLprev)
-        f = 1.0 / expansionRatio**2
-        self.changeNDensByFactor(f)
-        self.clearLinkedCache()
+        Change the number density of all nuclides within the object by a multiplicative factor.
+        Don't call `updateNumberDensities` to avoid a circular call stack.
+        """
+        for nuc, val in self.getNumberDensities().items():
+            self.p.numberDensities[nuc] = val * factor
+
+        if self.p.detailedNDens is not None:
+            self.p.detailedNDens *= factor
+        # Update pinNDens
+        if self.p.pinNDens is not None:
+            self.p.pinNDens *= factor
 
     def getNuclides(self):
         """
@@ -817,14 +793,12 @@ def updateNumberDensities(self, numberDensities):
         """
         # prepare to change the densities with knowledge that dims could change due to
         # material thermal expansion dependence on composition
-        dLLprev = self.material.linearExpansionPercent(Tc=self.temperatureInC) / 100.0
-        try:
-            vol = self.getVolume()
-        except:
-            # either no parent to get height or parent's height is None
-            # which would be AttributeError and TypeError respectively, but other errors could be possible
-            vol = None
-            area = self.getArea()
+        if len(self.p.numberDensities) > 0:
+            dLLprev = (
+                self.material.linearExpansionPercent(Tc=self.temperatureInC) / 100.0
+            )
+        else:
+            dLLprev = 0.0
 
         # change the densities
         self.p.numberDensities.update(numberDensities)
@@ -837,12 +811,9 @@ def updateNumberDensities(self, numberDensities):
             # (since the density change was for the old volume and otherwise mass wouldn't be conserved)
 
             # enable recalculation of volume, otherwise it uses stored.
-            self.clearLinkedCache()
-            if vol is not None:
-                factor = vol / self.getVolume()
-            else:
-                factor = area / self.getArea()
+            factor = (1.0 + dLLprev) ** 2 / (1.0 + dLLnew) ** 2
             self.changeNDensByFactor(factor)
+            self.clearLinkedCache()
 
         # since we're calling update on the object the param points to, but not the param itself, we have to inform
         # the param system to flag it as modified so it properly syncs during ``syncMpiState``.