• Clean up subchannel power mesh assumptions

  Remove unused detailed pin mesh generator code and an unused tri assembly
  helper. Make quad and tri power IC/Aux objects require a pin mesh and apply
  q_prime only on pin nodes. Update added-heat calculations to source heat from
  pin nodes only, returning zero for no-pin meshes. Refresh related power object
  documentation to match the pin-only behavior. Refs #32847

Author: kyriv1980

modules/subchannel/doc/content/source/auxkernels/SCMQuadPowerAux.md

@@ -12,8 +12,7 @@ This AuxKernel does the same thing as the [SCMQuadPowerIC](SCMQuadPowerIC.md) IC
 
 !! Intentional comment to provide extra spacing
 
-If the user has created a mesh for the pins, the axial heat rate `q_prime` will be assigned to the nodes of the pin mesh. If the user hasn't created a pin mesh the appropriate heat rate `q_prime` will be assigned to
-the nodes of the subchannel mesh.
+This AuxKernel requires a pin mesh. The axial heat rate `q_prime` is assigned only to the nodes of the pin mesh. If the subchannel mesh has no pin mesh, this object reports an error.
 
 !syntax parameters /AuxKernels/SCMQuadPowerAux
 

modules/subchannel/doc/content/source/auxkernels/SCMTriPowerAux.md

@@ -12,8 +12,7 @@ This AuxKernel does the same thing as the [SCMTriPowerIC](SCMTriPowerIC.md) IC k
 
 !! Intentional comment to provide extra spacing
 
-If the user has created a mesh for the pins, the axial heat rate `q_prime` will be assigned to the nodes of the pin mesh. If the user hasn't created a pin mesh the appropriate heat rate `q_prime` will be assigned to
-the nodes of the subchannel mesh.
+This AuxKernel requires a pin mesh. The axial heat rate `q_prime` is assigned only to the nodes of the pin mesh. If the subchannel mesh has no pin mesh, this object reports an error.
 
 !syntax parameters /AuxKernels/SCMTriPowerAux
 

modules/subchannel/doc/content/source/ics/SCMQuadPowerIC.md

@@ -6,7 +6,7 @@
 
 !! Intentional comment to provide extra spacing
 
-This IC assigns the axial heat rate ([!param](/ICs/SCMQuadPowerIC/variable) = `q_prime`) on the subchannels or pins in the case of a problem with subchannels/pins in a square lattice arrangement.
+This IC assigns the axial heat rate ([!param](/ICs/SCMQuadPowerIC/variable) = `q_prime`) to the fuel pins in a square lattice arrangement.
 
 The user must provide the  total power of the subassembly [!param](/ICs/SCMQuadPowerIC/power), the axial shape of the power profile and the radial power distribution (power per pin). The axial power profile is given as a function over the -z direction, which integral over the length of the heated portion of the pin, is equal to the length of the heated portion of the pin. The radial power distribution is given as a column of numbers in a .txt file [!param](/ICs/SCMQuadPowerIC/filename) that has as many entries as the number of pins.
 
@@ -24,8 +24,7 @@ The axial heat rate at a specific height is the product of the total power of th
 
 !! Intentional comment to provide extra spacing
 
-If the user has created a mesh for the pins, the axial heat rate will be assigned to the nodes of the pin mesh. If the user hasn't created a pin mesh the appropriate heat rate will be assigned to
-the nodes of the subchannel mesh. When the user has defined a fuel-pin mesh, the axial heat rate ([!param](/ICs/SCMTriPowerIC/variable) = `q_prime`) is the heat rate at the surface of the fuels pins and it is distributed equally to each neighboring subchannel.
+This IC requires a pin mesh. The axial heat rate ([!param](/ICs/SCMQuadPowerIC/variable) = `q_prime`) is assigned only to the nodes of the pin mesh. If the subchannel mesh has no pin mesh, this object reports an error. The subchannel solver distributes this pin heat to neighboring subchannels when computing the heat added to the coolant.
 
 !syntax parameters /ICs/SCMQuadPowerIC
 

modules/subchannel/doc/content/source/ics/SCMTriPowerIC.md

@@ -6,7 +6,7 @@
 
 !! Intentional comment to provide extra spacing
 
-This IC assigns the axial heat rate ([!param](/ICs/SCMTriPowerIC/variable) = `q_prime`) on the subchannels or pins in the case of a problem with subchannels/pins in a triangular lattice arrangement.
+This IC assigns the axial heat rate ([!param](/ICs/SCMTriPowerIC/variable) = `q_prime`) to the fuel pins in a triangular lattice arrangement.
 
 The user must provide the total power of the subassembly [!param](/ICs/SCMTriPowerIC/power), the axial shape of the power profile and the radial
 power distribution (power per pin). The axial power profile is given as a function, which integral over the length of the heated portion of the pin, is equal
@@ -26,8 +26,7 @@ The axial heat rate at a specific height is the product of the total power of th
 
 !! Intentional comment to provide extra spacing
 
-If the user has created a mesh for the pins, the axial hear rate will be assigned to the nodes of the pin mesh. If the user hasn't created a pin mesh the appropiate heat rate will be assigned to
-the nodes of the subchannel mesh. When the user has defined a fuel-pin mesh, the axial heat rate ([!param](/ICs/SCMTriPowerIC/variable) = `q_prime`) is the heat rate at the surface of the fuels pins and it is distributed equally to each neighboring subchannel.
+This IC requires a pin mesh. The axial heat rate ([!param](/ICs/SCMTriPowerIC/variable) = `q_prime`) is assigned only to the nodes of the pin mesh. If the subchannel mesh has no pin mesh, this object reports an error. The subchannel solver distributes this pin heat to neighboring subchannels when computing the heat added to the coolant.
 
 !syntax parameters /ICs/SCMTriPowerIC
 

modules/subchannel/doc/content/source/postprocessors/SCMPinPowerPostprocessor.md

@@ -6,7 +6,7 @@
 
 !! this comment introduces vertical space
 
-The user needs to specify a subchannel problem. Either a [QuadSubChannel1PhaseProblem.md] or a [TriSubChannel1PhaseProblem.md]. The postprocessor will calculate the total heat rate $[W]$ that goes into the coolant, based on the distribution of the aux variable q_prime $[W/m]$, on the fuel pins or the subchannels. It will integrate this variable over the heated section using an axial trapezoidal rule.
+The user needs to specify a subchannel problem. Either a [QuadSubChannel1PhaseProblem.md] or a [TriSubChannel1PhaseProblem.md]. The postprocessor will calculate the total heat rate $[W]$ that goes into the coolant, based on the distribution of the aux variable q_prime $[W/m]$ on the fuel pins. It will integrate this variable over the heated section using an axial trapezoidal rule.
 
 ## Example Input File Syntax
 

modules/subchannel/include/auxkernels/SCMQuadPowerAux.h

@@ -34,7 +34,7 @@ class SCMQuadPowerAux : public AuxKernel
   unsigned int _numberoflines;
   /// The name of the radial power profile file
   std::string _filename;
-  /// matrix that holds the values of the relative pin power
+  /// Matrix that holds the relative pin power
   Eigen::MatrixXd _power_dis;
   const Function & _axial_heat_rate;
   /// Average linear heat rate over the whole pin [W/m]

modules/subchannel/include/ics/SCMQuadPowerIC.h

@@ -30,7 +30,7 @@ class SCMQuadPowerIC : public QuadSubChannelBaseIC
   unsigned int _numberoflines;
   /// The name of the radial power profile file
   std::string _filename;
-  /// matrix that holds the values of the relative pin power
+  /// Matrix that holds the relative pin power
   Eigen::MatrixXd _power_dis;
   const Function & _axial_heat_rate;
   /// Average linear heat rate over the whole pin [W/m]

modules/subchannel/include/meshgenerators/DetailedPinMeshGeneratorBase.h

@@ -25,7 +25,6 @@ class SCMDetailedTriAssemblyMeshGenerator : public MeshGenerator
   /// returns the type of the subchannel given the index
   EChannelType getSubchannelType(unsigned int index) const { return _subch_type[index]; }
   Point rotatePoint(Point b, Real theta);
-  Point translatePoint(Point & b, Point & translation_vector);
   void generatePin(std::unique_ptr<MeshBase> & mesh_base, const Point & center);
   /// returns the position of pin given pin index
   Point getPinPosition(unsigned int i) { return _pin_position[i]; }

modules/subchannel/include/meshgenerators/SCMDetailedTriAssemblyMeshGenerator.h

@@ -20,8 +20,8 @@ SCMQuadPowerAux::validParams()
 {
   InputParameters params = AuxKernel::validParams();
   params.addClassDescription(
-      "Computes axial power rate (W/m) that goes into the subchannel cells "
-      "or is assigned to the fuel pins, in a quadrilateral lattice arrangement");
+      "Computes axial power rate (W/m) assigned to the fuel pins in a quadrilateral lattice "
+      "arrangement");
   params.addRequiredParam<PostprocessorName>(
       "power", "The postprocessor or Real to use for the total power of the subassembly [W]");
   params.addRequiredParam<std::string>(
@@ -44,12 +44,14 @@ SCMQuadPowerAux::SCMQuadPowerAux(const InputParameters & parameters)
   if (processor_id() > 0)
     return;
 
-  auto nx = _quadMesh.getNx();
-  auto ny = _quadMesh.getNy();
+  if (!_quadMesh.pinMeshExist())
+    mooseError(name(), ": This object requires a pin mesh.");
+
+  auto n_pins = _quadMesh.getNumOfPins();
   // Matrix sizing
-  _power_dis.resize((ny - 1) * (nx - 1), 1);
+  _power_dis.resize(n_pins, 1);
   _power_dis.setZero();
-  _pin_power_correction.resize((ny - 1) * (nx - 1), 1);
+  _pin_power_correction.resize(n_pins, 1);
   _pin_power_correction.setOnes();
 
   Real vin;
@@ -65,8 +67,8 @@ SCMQuadPowerAux::SCMQuadPowerAux(const InputParameters & parameters)
   if (inFile.fail() && !inFile.eof())
     mooseError(name(), " non numerical input at line : ", _numberoflines);
 
-  if (_numberoflines != (ny - 1) * (nx - 1))
-    mooseError(name(), " Radial profile file doesn't have correct size : ", (ny - 1) * (nx - 1));
+  if (_numberoflines != n_pins)
+    mooseError(name(), " Radial profile file doesn't have correct size : ", n_pins);
   inFile.close();
 
   inFile.open(_filename);
@@ -86,9 +88,7 @@ SCMQuadPowerAux::initialSetup()
   if (processor_id() > 0)
     return;
 
-  auto nx = _quadMesh.getNx();
-  auto ny = _quadMesh.getNy();
-  auto n_pins = (nx - 1) * (ny - 1);
+  auto n_pins = _quadMesh.getNumOfPins();
   auto nz = _quadMesh.getNumOfAxialCells();
   auto z_grid = _quadMesh.getZGrid();
   auto heated_length = _quadMesh.getHeatedLength();
@@ -169,31 +169,13 @@ SCMQuadPowerAux::computeValue()
   auto unheated_length_entry = _quadMesh.getHeatedLengthEntry();
   Point p1(0, 0, unheated_length_entry);
   Point P = p - p1;
-  auto pin_mesh_exist = _quadMesh.pinMeshExist();
 
   /// assign power to the nodes located within the heated section
   if (MooseUtils::absoluteFuzzyGreaterEqual(p(2), unheated_length_entry) &&
       MooseUtils::absoluteFuzzyLessEqual(p(2), unheated_length_entry + heated_length))
   {
-    if (pin_mesh_exist)
-    {
-      // project axial heat rate on pins
-      auto i_pin = _quadMesh.getPinIndexFromPoint(p);
-      return _ref_qprime(i_pin) * _pin_power_correction(i_pin) * _axial_heat_rate.value(_t, P);
-    }
-    else
-    {
-      // project axial heat rate on subchannels
-      auto i_ch = _quadMesh.getSubchannelIndexFromPoint(p);
-      // if we are adjacent to the heated part of the fuel Pin
-      auto heat_rate = 0.0;
-      for (auto i_pin : _quadMesh.getChannelPins(i_ch))
-      {
-        heat_rate += 0.25 * _ref_qprime(i_pin) * _pin_power_correction(i_pin) *
-                     _axial_heat_rate.value(_t, P);
-      }
-      return heat_rate;
-    }
+    auto i_pin = _quadMesh.getPinIndexFromPoint(p);
+    return _ref_qprime(i_pin) * _pin_power_correction(i_pin) * _axial_heat_rate.value(_t, P);
   }
   else
     return 0.0;