From 5c04eb0d3baceb066b723bd04e20e5229bb3267f Mon Sep 17 00:00:00 2001
From: Shikhar Kumar <shikhark@mit.edu>
Date: Wed, 12 Dec 2018 12:20:48 -0500
Subject: [PATCH] Update test suite with 2g, ng solvers

---
 include/openmc/constants.h                    |   2 +-
 openmc/cmfd.py                                |  21 +-
 tests/regression_tests/cmfd_feed/test.py      | 120 +++-
 .../cmfd_feed_2g/geometry.xml                 |  31 +
 .../cmfd_feed_2g/materials.xml                |  59 ++
 .../cmfd_feed_2g/results_true.dat             | 434 ++++++++++++
 .../cmfd_feed_2g/settings.xml                 |  25 +
 .../regression_tests/cmfd_feed_2g/tallies.xml |  21 +
 tests/regression_tests/cmfd_feed_2g/test.py   |  46 ++
 .../cmfd_feed_ng/geometry.xml                 |  31 +
 .../cmfd_feed_ng/materials.xml                |  59 ++
 .../cmfd_feed_ng/results_true.dat             | 621 ++++++++++++++++++
 .../cmfd_feed_ng/settings.xml                 |  25 +
 .../regression_tests/cmfd_feed_ng/tallies.xml |  21 +
 tests/regression_tests/cmfd_feed_ng/test.py   |  47 ++
 tests/regression_tests/cmfd_nofeed/test.py    |  24 +-
 tests/testing_harness.py                      |   9 +
 17 files changed, 1575 insertions(+), 21 deletions(-)
 create mode 100644 tests/regression_tests/cmfd_feed_2g/geometry.xml
 create mode 100644 tests/regression_tests/cmfd_feed_2g/materials.xml
 create mode 100644 tests/regression_tests/cmfd_feed_2g/results_true.dat
 create mode 100644 tests/regression_tests/cmfd_feed_2g/settings.xml
 create mode 100644 tests/regression_tests/cmfd_feed_2g/tallies.xml
 create mode 100644 tests/regression_tests/cmfd_feed_2g/test.py
 create mode 100644 tests/regression_tests/cmfd_feed_ng/geometry.xml
 create mode 100644 tests/regression_tests/cmfd_feed_ng/materials.xml
 create mode 100644 tests/regression_tests/cmfd_feed_ng/results_true.dat
 create mode 100644 tests/regression_tests/cmfd_feed_ng/settings.xml
 create mode 100644 tests/regression_tests/cmfd_feed_ng/tallies.xml
 create mode 100644 tests/regression_tests/cmfd_feed_ng/test.py

diff --git a/include/openmc/constants.h b/include/openmc/constants.h
index 96fc19b2bd..7697843510 100644
--- a/include/openmc/constants.h
+++ b/include/openmc/constants.h
@@ -438,7 +438,7 @@ constexpr int RUN_MODE_VOLUME      {5};
 // CMFD CONSTANTS
 
 // For non-accelerated regions on coarse mesh overlay
-constexpr int CMFD_NOACCEL {99999};
+constexpr int CMFD_NOACCEL {-1};
 
 } // namespace openmc
 
diff --git a/openmc/cmfd.py b/openmc/cmfd.py
index bb40da618e..5626f72eed 100644
--- a/openmc/cmfd.py
+++ b/openmc/cmfd.py
@@ -252,6 +252,10 @@ class CMFDRun(object):
              CMFD problem
           * "math" - Create adjoint matrices mathematically as the transpose of
              loss and production CMFD matrices
+    indices : numpy.ndarray
+        Stores spatial and group dimensions as [nx, ny, nz, ng]
+    cmfd_src : numpy.ndarray
+        CMFD source distribution calculated from solving CMFD equations
     entropy : list of floats
         "Shannon entropy" from cmfd fission source, stored for each generation
         that CMFD is invoked
@@ -443,6 +447,14 @@ class CMFDRun(object):
     def gauss_seidel_tolerance(self):
         return self._gauss_seidel_tolerance
 
+    @property
+    def indices(self):
+        return self._indices
+
+    @property
+    def cmfd_src(self):
+        return self._cmfd_src
+
     @property
     def dom(self):
         return self._dom
@@ -555,7 +567,7 @@ class CMFDRun(object):
     def adjoint_type(self, adjoint_type):
         check_type('CMFD adjoint type', adjoint_type, str)
         check_value('CMFD adjoint type', adjoint_type,
-                    ['math', 'phyical'])
+                    ['math', 'physical'])
         self._adjoint_type = adjoint_type
 
     @power_monitor.setter
@@ -1005,7 +1017,7 @@ class CMFDRun(object):
                 # Get all data entries for particular row in matrix
                 data = matrix.data[matrix.indptr[row]:matrix.indptr[row+1]]
                 for i in range(len(cols)):
-                    fh.write('({:3d}, {:3d}): {:0.8f}\n'.format(
+                    fh.write('{:3d}, {:3d}, {:0.8f}\n'.format(
                         row, cols[i], data[i]))
 
         # Save matrix in scipy format
@@ -1572,8 +1584,9 @@ class CMFDRun(object):
         kerr = abs(k_o - k_n) / k_n
 
         # Calculate max error in source
-        serr = np.sqrt(np.sum(np.where(s_n > 0, ((s_n-s_o) / s_n)**2, 0))
-                       / len(s_n))
+        with np.errstate(divide='ignore', invalid='ignore'):
+            serr = np.sqrt(np.sum(np.where(s_n > 0, ((s_n-s_o) / s_n)**2, 0))
+                           / len(s_n))
 
         # Check for convergence
         iconv = kerr < self._cmfd_ktol and serr < self._stol
diff --git a/tests/regression_tests/cmfd_feed/test.py b/tests/regression_tests/cmfd_feed/test.py
index 368e81aee2..61d4ae2eff 100644
--- a/tests/regression_tests/cmfd_feed/test.py
+++ b/tests/regression_tests/cmfd_feed/test.py
@@ -1,8 +1,17 @@
 from tests.testing_harness import CMFDTestHarness
 import openmc
 import numpy as np
+import scipy.sparse
 
-def test_cmfd_feed():
+def test_cmfd_physical_adjoint():
+    """ Test physical adjoint functionality of CMFD
+
+    This test runs CMFD with a physical adjoint calculation and asserts that the
+    adjoint k-effective and flux vector are equal to the non-adjoint
+    k-effective and flux vector at the last batch (equivalent for 1 group
+    problems).
+
+    """
     # Initialize and set CMFD mesh
     cmfd_mesh = openmc.CMFDMesh()
     cmfd_mesh.lower_left = -10.0, -1.0, -1.0
@@ -12,10 +21,111 @@ def test_cmfd_feed():
 
     # Initialize and run CMFDRun object
     cmfd_run = openmc.CMFDRun()
-    cmfd_run.cmfd_mesh = cmfd_mesh
-    cmfd_run.cmfd_begin = 5
-    cmfd_run.cmfd_display = 'dominance'
-    cmfd_run.cmfd_feedback = True
+    cmfd_run.mesh = cmfd_mesh
+    cmfd_run.begin = 5
+    cmfd_run.feedback = True
+    cmfd_run.gauss_seidel_tolerance = [1.e-15, 1.e-20]
+    cmfd_run.run_adjoint = True
+    cmfd_run.adjoint_type = 'physical'
+    cmfd_run.run()
+    assert(np.all(cmfd_run._phi == cmfd_run._adj_phi))
+    assert(cmfd_run._adj_keff == cmfd_run._keff)
+
+def test_cmfd_math_adjoint():
+    """ Test mathematical adjoint functionality of CMFD
+
+    This test runs CMFD with a mathematical adjoint calculation and asserts that
+    the adjoint k-effective and flux vector are equal to the non-adjoint
+    k-effective and flux vector at the last batch (equivalent for 1 group
+    problems).
+
+    """
+    # Initialize and set CMFD mesh
+    cmfd_mesh = openmc.CMFDMesh()
+    cmfd_mesh.lower_left = -10.0, -1.0, -1.0
+    cmfd_mesh.upper_right = 10.0, 1.0, 1.0
+    cmfd_mesh.dimension = 10, 1, 1
+    cmfd_mesh.albedo = 0.0, 0.0, 1.0, 1.0, 1.0, 1.0
+
+    # Initialize and run CMFDRun object
+    cmfd_run = openmc.CMFDRun()
+    cmfd_run.mesh = cmfd_mesh
+    cmfd_run.begin = 5
+    cmfd_run.feedback = True
+    cmfd_run.gauss_seidel_tolerance = [1.e-15, 1.e-20]
+    cmfd_run.run_adjoint = True
+    cmfd_run.adjoint_type = 'math'
+    cmfd_run.run()
+    assert(np.all(cmfd_run._phi == cmfd_run._adj_phi))
+    assert(cmfd_run._adj_keff == cmfd_run._keff)
+
+def test_cmfd_write_matrices():
+    """ Test write matrices functionality of CMFD
+
+    This test runs CMFD with feedback and loads the loss/production matrices
+    and flux vector that are saved to disk, and checks to make sure these
+    values are consistent with each other and simulation results.
+
+    """
+    # Initialize and set CMFD mesh
+    cmfd_mesh = openmc.CMFDMesh()
+    cmfd_mesh.lower_left = -10.0, -1.0, -1.0
+    cmfd_mesh.upper_right = 10.0, 1.0, 1.0
+    cmfd_mesh.dimension = 10, 1, 1
+    cmfd_mesh.albedo = 0.0, 0.0, 1.0, 1.0, 1.0, 1.0
+
+    # Initialize and run CMFDRun object
+    cmfd_run = openmc.CMFDRun()
+    cmfd_run.mesh = cmfd_mesh
+    cmfd_run.begin = 5
+    cmfd_run.display = {'dominance': True}
+    cmfd_run.feedback = True
+    cmfd_run.gauss_seidel_tolerance = [1.e-15, 1.e-20]
+    cmfd_run.write_matrices = True
+    cmfd_run.run()
+
+    # Load loss matrix from numpy output file
+    loss_np = scipy.sparse.load_npz('loss.npz').todense()
+    # Load loss matrix from data file
+    loss_dat = np.loadtxt("loss.dat", delimiter=',')
+
+    # Go through each element of loss_dat and compare to loss_np
+    for elem in loss_dat:
+        assert(np.isclose(loss_np[int(elem[0]), int(elem[1])], elem[2]))
+
+    # Load production matrix from numpy output file
+    prod_np = scipy.sparse.load_npz('prod.npz').todense()
+    # Load production matrix from data file
+    prod_dat = np.loadtxt("prod.dat", delimiter=',')
+
+    # Go through each element of prod_dat and compare to prod_np
+    for elem in prod_dat:
+        assert(np.isclose(prod_np[int(elem[0]), int(elem[1])], elem[2]))
+
+    # Load flux vector from numpy output file
+    flux_np = np.load('fluxvec.npy')
+    # Load flux from data file
+    flux_dat = np.loadtxt("fluxvec.dat", delimiter='\n')
+
+    # Compare flux from numpy file, .dat file, and from simulation
+    assert(np.all(np.isclose(flux_np, cmfd_run._phi)))
+    assert(np.all(np.isclose(flux_np, flux_dat)))
+
+def test_cmfd_feed():
+    """ Test 1 group CMFD solver with CMFD feedback"""
+    # Initialize and set CMFD mesh
+    cmfd_mesh = openmc.CMFDMesh()
+    cmfd_mesh.lower_left = -10.0, -1.0, -1.0
+    cmfd_mesh.upper_right = 10.0, 1.0, 1.0
+    cmfd_mesh.dimension = 10, 1, 1
+    cmfd_mesh.albedo = 0.0, 0.0, 1.0, 1.0, 1.0, 1.0
+
+    # Initialize and run CMFDRun object
+    cmfd_run = openmc.CMFDRun()
+    cmfd_run.mesh = cmfd_mesh
+    cmfd_run.begin = 5
+    cmfd_run.display = {'dominance': True}
+    cmfd_run.feedback = True
     cmfd_run.gauss_seidel_tolerance = [1.e-15, 1.e-20]
     cmfd_run.run()
 
diff --git a/tests/regression_tests/cmfd_feed_2g/geometry.xml b/tests/regression_tests/cmfd_feed_2g/geometry.xml
new file mode 100644
index 0000000000..9fdd2ddcb6
--- /dev/null
+++ b/tests/regression_tests/cmfd_feed_2g/geometry.xml
@@ -0,0 +1,31 @@
+<?xml version='1.0' encoding='utf-8'?>
+<geometry>
+  <cell id="1" fill="5" region="151 -152 153 -154 1380 -1370" />
+
+  <cell id="52" material="9" name="Fuel rod active region - 1.6% enr radial 0: Fuel 1.6%" region="-35" universe="8" />
+  <cell id="53" material="5" name="Fuel rod active region - 1.6% enr radial 1: Helium" region="35 -36" universe="8" />
+  <cell id="54" material="7" name="Fuel rod active region - 1.6% enr radial outer: Zircaloy 4" region="36" universe="8" />
+  <cell fill="8" id="1253" name="Fuel cell" region="-150" universe="763" />
+  <cell id="1254" material="15" name="Water" region="150" universe="763" />
+
+  <lattice id="5">
+    <dimension>2 2</dimension>
+    <lower_left>-1.25984 -1.25984</lower_left>
+    <pitch>1.25984 1.25984</pitch>
+    <universes>
+      763 763
+      763 763
+    </universes>
+  </lattice>
+
+  <surface coeffs="0.0 0.0 0.39218" id="35" name="Fuel pellet OR" type="z-cylinder" />
+  <surface coeffs="0.0 0.0 0.40005" id="36" name="Fuel clad IR" type="z-cylinder" />
+  <surface coeffs="0.0 0.0 0.4572" id="150" name="Fuel clad OR" type="z-cylinder" />
+  <surface boundary="reflective" coeffs="-1.25984" id="151" name="minimum x" type="x-plane" />
+  <surface boundary="reflective" coeffs="1.25984" id="152" name="maximum x" type="x-plane" />
+  <surface boundary="reflective" coeffs="-1.25984" id="153" name="minimum y" type="y-plane" />
+  <surface boundary="reflective" coeffs="1.25984" id="154" name="maximum y" type="y-plane" />
+  <surface boundary="reflective" coeffs="1.0" id="1370" name="Highest Extent" type="z-plane" />
+  <surface boundary="reflective" coeffs="-1.0" id="1380" name="Lowest Extent" type="z-plane" />
+
+</geometry>
diff --git a/tests/regression_tests/cmfd_feed_2g/materials.xml b/tests/regression_tests/cmfd_feed_2g/materials.xml
new file mode 100644
index 0000000000..bfa2d8842d
--- /dev/null
+++ b/tests/regression_tests/cmfd_feed_2g/materials.xml
@@ -0,0 +1,59 @@
+<?xml version='1.0' encoding='utf-8'?>
+<materials>
+  <material id="5" name="Helium">
+    <temperature>300</temperature>
+    <density units="g/cc" value="0.0015981" />
+    <nuclide name="He3" wo="1.5070346049256974e-06" />
+    <nuclide name="He4" wo="0.999998492965395" />
+  </material>
+  <material id="7" name="Zircaloy 4">
+    <temperature>300</temperature>
+    <density units="g/cc" value="6.55" />
+    <nuclide name="O16" wo="0.0012494965182849112" />
+    <nuclide name="O17" wo="5.034817150887735e-07" />
+    <nuclide name="Cr50" wo="4.1736864731106146e-05" />
+    <nuclide name="Cr52" wo="0.0008369936242576807" />
+    <nuclide name="Cr53" wo="9.673586881507429e-05" />
+    <nuclide name="Cr54" wo="2.4533642196138756e-05" />
+    <nuclide name="Fe54" wo="0.00011855672274761877" />
+    <nuclide name="Fe56" wo="0.001929932104229657" />
+    <nuclide name="Fe57" wo="4.536774095388075e-05" />
+    <nuclide name="Fe58" wo="6.143432068843669e-06" />
+    <nuclide name="Zr90" wo="0.49750307249921255" />
+    <nuclide name="Zr91" wo="0.10970127796055709" />
+    <nuclide name="Zr92" wo="0.16952409354767467" />
+    <nuclide name="Zr94" wo="0.17553856942304608" />
+    <nuclide name="Zr96" wo="0.02888298656950975" />
+    <nuclide name="Sn112" wo="0.0001325869644430062" />
+    <nuclide name="Sn114" wo="9.182449637587617e-05" />
+    <nuclide name="Sn115" wo="4.771905922545867e-05" />
+    <nuclide name="Sn116" wo="0.002058423153629443" />
+    <nuclide name="Sn117" wo="0.0010966473429083066" />
+    <nuclide name="Sn118" wo="0.0034879812938438245" />
+    <nuclide name="Sn119" wo="0.001247577110245757" />
+    <nuclide name="Sn120" wo="0.004771539495238715" />
+    <nuclide name="Sn122" wo="0.0006894094798456136" />
+    <nuclide name="Sn124" wo="0.000876291604244001" />
+  </material>
+  <material depletable="true" id="9" name="Fuel 1.6%">
+    <temperature>300</temperature>
+    <density units="g/cc" value="10.31341" />
+    <nuclide ao="1.9992419999999993" name="O16" />
+    <nuclide ao="0.0007579999999999998" name="O17" />
+    <nuclide ao="0.00014571996318473284" name="U234" />
+    <nuclide ao="0.01630316269333107" name="U235" />
+    <nuclide ao="0.983476441027697" name="U238" />
+    <nuclide ao="7.467631578722921e-05" name="U236" />
+  </material>
+  <material id="15" name="Borated Water">
+    <temperature>300</temperature>
+    <density units="g/cc" value="0.7405820675158279" />
+    <nuclide ao="0.00032178659941803253" name="B10" />
+    <nuclide ao="0.0013017583017829388" name="B11" />
+    <nuclide ao="1.996441935899364" name="H1" />
+    <nuclide ao="0.0003109742982341739" name="H2" />
+    <nuclide ao="0.9979980704223166" name="O16" />
+    <nuclide ao="0.0003783846764824448" name="O17" />
+    <sab name="c_H_in_H2O" />
+  </material>
+</materials>
diff --git a/tests/regression_tests/cmfd_feed_2g/results_true.dat b/tests/regression_tests/cmfd_feed_2g/results_true.dat
new file mode 100644
index 0000000000..2be15c4e88
--- /dev/null
+++ b/tests/regression_tests/cmfd_feed_2g/results_true.dat
@@ -0,0 +1,434 @@
+k-combined:
+1.038883E+00 1.017026E-02
+tally 1:
+1.167304E+02
+1.362680E+03
+1.157179E+02
+1.339273E+03
+1.167087E+02
+1.362782E+03
+1.164493E+02
+1.356411E+03
+tally 2:
+4.400233E+01
+9.698989E+01
+6.541957E+01
+2.144299E+02
+1.863245E+02
+1.738212E+03
+1.038047E+02
+5.390768E+02
+4.368854E+01
+9.564001E+01
+6.489620E+01
+2.109923E+02
+1.836691E+02
+1.687792E+03
+1.022706E+02
+5.232407E+02
+4.433402E+01
+9.859049E+01
+6.548060E+01
+2.150470E+02
+1.839219E+02
+1.692209E+03
+1.031634E+02
+5.323852E+02
+4.380686E+01
+9.606723E+01
+6.480355E+01
+2.103905E+02
+1.868847E+02
+1.747254E+03
+1.038109E+02
+5.391360E+02
+tally 3:
+6.192979E+01
+1.921761E+02
+0.000000E+00
+0.000000E+00
+2.033842E-02
+4.375294E-05
+4.296338E+00
+9.280716E-01
+3.493776E+00
+6.157094E-01
+0.000000E+00
+0.000000E+00
+9.876716E+01
+4.880113E+02
+9.043140E-01
+4.156054E-02
+6.138292E+01
+1.887853E+02
+0.000000E+00
+0.000000E+00
+1.591722E-02
+2.328432E-05
+4.296798E+00
+9.289349E-01
+3.584967E+00
+6.444749E-01
+0.000000E+00
+0.000000E+00
+9.717439E+01
+4.724254E+02
+8.435691E-01
+3.666151E-02
+6.192881E+01
+1.924016E+02
+0.000000E+00
+0.000000E+00
+1.796382E-02
+3.190854E-05
+4.343238E+00
+9.514039E-01
+3.504683E+00
+6.157615E-01
+0.000000E+00
+0.000000E+00
+9.818871E+01
+4.822799E+02
+8.401346E-01
+3.664037E-02
+6.130607E+01
+1.882837E+02
+0.000000E+00
+0.000000E+00
+1.220252E-02
+1.711667E-05
+4.245413E+00
+9.056738E-01
+3.468894E+00
+6.033679E-01
+0.000000E+00
+0.000000E+00
+9.885292E+01
+4.888720E+02
+9.509199E-01
+4.670951E-02
+tally 4:
+0.000000E+00
+0.000000E+00
+0.000000E+00
+0.000000E+00
+0.000000E+00
+0.000000E+00
+0.000000E+00
+0.000000E+00
+9.200260E+00
+4.243011E+00
+3.728022E+01
+6.953801E+01
+9.178009E+00
+4.218903E+00
+3.738925E+01
+6.993833E+01
+0.000000E+00
+0.000000E+00
+0.000000E+00
+0.000000E+00
+0.000000E+00
+0.000000E+00
+0.000000E+00
+0.000000E+00
+9.019225E+00
+4.079528E+00
+3.709185E+01
+6.883085E+01
+9.037478E+00
+4.095846E+00
+3.710303E+01
+6.888447E+01
+0.000000E+00
+0.000000E+00
+0.000000E+00
+0.000000E+00
+0.000000E+00
+0.000000E+00
+0.000000E+00
+0.000000E+00
+0.000000E+00
+0.000000E+00
+0.000000E+00
+0.000000E+00
+0.000000E+00
+0.000000E+00
+0.000000E+00
+0.000000E+00
+9.178009E+00
+4.218903E+00
+3.738925E+01
+6.993833E+01
+9.200260E+00
+4.243011E+00
+3.728022E+01
+6.953801E+01
+0.000000E+00
+0.000000E+00
+0.000000E+00
+0.000000E+00
+0.000000E+00
+0.000000E+00
+0.000000E+00
+0.000000E+00
+0.000000E+00
+0.000000E+00
+0.000000E+00
+0.000000E+00
+0.000000E+00
+0.000000E+00
+0.000000E+00
+0.000000E+00
+9.097360E+00
+4.147125E+00
+3.700603E+01
+6.851110E+01
+9.003417E+00
+4.059372E+00
+3.717266E+01
+6.912709E+01
+0.000000E+00
+0.000000E+00
+0.000000E+00
+0.000000E+00
+0.000000E+00
+0.000000E+00
+0.000000E+00
+0.000000E+00
+0.000000E+00
+0.000000E+00
+0.000000E+00
+0.000000E+00
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+tally 5:
+6.195013E+01
+1.923032E+02
+1.022516E+02
+5.230716E+02
+1.418310E+01
+1.011490E+01
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+1.023107E+02
+5.236668E+02
+1.375796E+01
+9.501501E+00
+4.638162E+01
+1.076532E+02
+cmfd indices
+2.000000E+00
+2.000000E+00
+1.000000E+00
+2.000000E+00
+k cmfd
+1.034617E+00
+1.034521E+00
+1.036479E+00
+1.035658E+00
+1.032505E+00
+1.027277E+00
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+1.031963E+00
+1.034797E+00
+1.035383E+00
+1.035908E+00
+1.035629E+00
+1.036034E+00
+cmfd entropy
+1.999493E+00
+1.999058E+00
+1.999331E+00
+1.999370E+00
+1.999383E+00
+1.999455E+00
+1.999640E+00
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+1.999973E+00
+1.999965E+00
+1.999972E+00
+1.999982E+00
+1.999998E+00
+1.999984E+00
+cmfd balance
+3.993043E-04
+4.168558E-04
+6.384693E-04
+3.928217E-04
+3.789833E-04
+2.684860E-04
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+4.455545E-04
+4.011468E-04
+3.710248E-04
+3.577152E-04
+3.845993E-04
+3.900672E-04
+cmfd dominance ratio
+ 6.239E-03
+ 6.303E-03
+ 6.347E-03
+ 6.388E-03
+ 6.340E-03
+ 6.334E-03
+ 6.270E-03
+ 6.173E-03
+ 6.068E-03
+ 6.061E-03
+ 6.016E-03
+ 6.108E-03
+ 6.117E-03
+ 6.074E-03
+ 6.005E-03
+ 5.996E-03
+cmfd openmc source comparison
+1.931386E-05
+2.839162E-05
+1.407962E-05
+6.718148E-06
+9.164193E-06
+1.382539E-05
+2.871606E-05
+4.192300E-05
+5.327516E-05
+6.566500E-05
+6.655541E-05
+6.034977E-05
+6.004677E-05
+5.711623E-05
+6.271264E-05
+6.425363E-05
+cmfd source
+2.510278E-01
+2.480592E-01
+2.501750E-01
+2.507380E-01
+0.000000E+00
+0.000000E+00
+0.000000E+00
+0.000000E+00
diff --git a/tests/regression_tests/cmfd_feed_2g/settings.xml b/tests/regression_tests/cmfd_feed_2g/settings.xml
new file mode 100644
index 0000000000..9e483e6a09
--- /dev/null
+++ b/tests/regression_tests/cmfd_feed_2g/settings.xml
@@ -0,0 +1,25 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<settings>
+
+  <!-- Parameters for criticality calculation -->
+  <run_mode>eigenvalue</run_mode>
+  <batches>20</batches>
+  <inactive>10</inactive>
+  <particles>1000</particles>
+
+  <!-- Starting source -->
+  <source strength="1.0">
+    <space type="fission">
+      <parameters>-1.25984 -1.25984 -1 1.25984 1.25984 1</parameters>
+    </space>
+  </source>
+
+  <!-- Shannon Entropy -->
+  <mesh id="10">
+    <dimension> 2 2 1 </dimension>
+    <lower_left> -1.25984 -1.25984 -1.0 </lower_left>
+    <upper_right> 1.25984 1.25984 1.0 </upper_right>
+  </mesh>
+  <entropy_mesh>10</entropy_mesh>
+
+</settings>
diff --git a/tests/regression_tests/cmfd_feed_2g/tallies.xml b/tests/regression_tests/cmfd_feed_2g/tallies.xml
new file mode 100644
index 0000000000..477a078331
--- /dev/null
+++ b/tests/regression_tests/cmfd_feed_2g/tallies.xml
@@ -0,0 +1,21 @@
+<?xml version="1.0"?>
+<tallies>
+
+  <mesh id="1">
+    <type>regular</type>
+    <lower_left>-1.25984 -1.25984 -1.0 </lower_left>
+    <upper_right>1.25984 1.25984 1.0</upper_right>
+    <dimension>2 2 1</dimension>
+  </mesh>
+
+  <filter id="1">
+    <type>mesh</type>
+    <bins>1</bins>
+  </filter>
+
+  <tally id="1">
+    <filters>1</filters>
+    <scores>flux</scores>
+  </tally>
+
+</tallies>
diff --git a/tests/regression_tests/cmfd_feed_2g/test.py b/tests/regression_tests/cmfd_feed_2g/test.py
new file mode 100644
index 0000000000..8377e208a8
--- /dev/null
+++ b/tests/regression_tests/cmfd_feed_2g/test.py
@@ -0,0 +1,46 @@
+from tests.testing_harness import CMFDTestHarness
+import openmc
+import numpy as np
+
+def test_cmfd_feed_2g():
+    """ Test 2 group CMFD solver results with CMFD feedback"""
+    # Initialize and set CMFD mesh
+    cmfd_mesh = openmc.CMFDMesh()
+    cmfd_mesh.lower_left = -1.25984, -1.25984, -1.0
+    cmfd_mesh.upper_right = 1.25984, 1.25984, 1.0
+    cmfd_mesh.dimension = 2, 2, 1
+    cmfd_mesh.energy = [0.0, 0.625, 20000000]
+    cmfd_mesh.albedo = 1.0, 1.0, 1.0, 1.0, 1.0, 1.0
+
+    # Initialize and run CMFDRun object
+    cmfd_run = openmc.CMFDRun()
+    cmfd_run.mesh = cmfd_mesh
+    cmfd_run.begin = 5
+    cmfd_run.display = {'dominance': True}
+    cmfd_run.feedback = True
+    cmfd_run.downscatter = True
+    cmfd_run.gauss_seidel_tolerance = [1.e-15, 1.e-20]
+    cmfd_run.run()
+
+    # Create output string of all CMFD results to pass into testing harness
+    outstr = 'cmfd indices\n'
+    outstr += '\n'.join(['{0:12.6E}'.format(x) for x in cmfd_run._indices])
+    outstr += '\nk cmfd\n'
+    outstr += '\n'.join(['{0:12.6E}'.format(x) for x in cmfd_run._k_cmfd])
+    outstr += '\ncmfd entropy\n'
+    outstr += '\n'.join(['{0:12.6E}'.format(x) for x in cmfd_run._entropy])
+    outstr += '\ncmfd balance\n'
+    outstr += '\n'.join(['{0:12.6E}'.format(x) for x in cmfd_run._balance])
+    outstr += '\ncmfd dominance ratio\n'
+    outstr += '\n'.join(['{0:10.3E}'.format(x) for x in cmfd_run._dom])
+    outstr += '\ncmfd openmc source comparison\n'
+    outstr += '\n'.join(['{0:12.6E}'.format(x) for x in cmfd_run._src_cmp])
+    outstr += '\ncmfd source\n'
+    cmfdsrc = np.reshape(cmfd_run._cmfd_src, np.product(cmfd_run._indices),
+                         order='F')
+    outstr += '\n'.join(['{0:12.6E}'.format(x) for x in cmfdsrc])
+    outstr += '\n'
+
+    # Initialize and run CMFD test harness
+    harness = CMFDTestHarness('statepoint.20.h5', cmfd_results=outstr)
+    harness.main()
diff --git a/tests/regression_tests/cmfd_feed_ng/geometry.xml b/tests/regression_tests/cmfd_feed_ng/geometry.xml
new file mode 100644
index 0000000000..9fdd2ddcb6
--- /dev/null
+++ b/tests/regression_tests/cmfd_feed_ng/geometry.xml
@@ -0,0 +1,31 @@
+<?xml version='1.0' encoding='utf-8'?>
+<geometry>
+  <cell id="1" fill="5" region="151 -152 153 -154 1380 -1370" />
+
+  <cell id="52" material="9" name="Fuel rod active region - 1.6% enr radial 0: Fuel 1.6%" region="-35" universe="8" />
+  <cell id="53" material="5" name="Fuel rod active region - 1.6% enr radial 1: Helium" region="35 -36" universe="8" />
+  <cell id="54" material="7" name="Fuel rod active region - 1.6% enr radial outer: Zircaloy 4" region="36" universe="8" />
+  <cell fill="8" id="1253" name="Fuel cell" region="-150" universe="763" />
+  <cell id="1254" material="15" name="Water" region="150" universe="763" />
+
+  <lattice id="5">
+    <dimension>2 2</dimension>
+    <lower_left>-1.25984 -1.25984</lower_left>
+    <pitch>1.25984 1.25984</pitch>
+    <universes>
+      763 763
+      763 763
+    </universes>
+  </lattice>
+
+  <surface coeffs="0.0 0.0 0.39218" id="35" name="Fuel pellet OR" type="z-cylinder" />
+  <surface coeffs="0.0 0.0 0.40005" id="36" name="Fuel clad IR" type="z-cylinder" />
+  <surface coeffs="0.0 0.0 0.4572" id="150" name="Fuel clad OR" type="z-cylinder" />
+  <surface boundary="reflective" coeffs="-1.25984" id="151" name="minimum x" type="x-plane" />
+  <surface boundary="reflective" coeffs="1.25984" id="152" name="maximum x" type="x-plane" />
+  <surface boundary="reflective" coeffs="-1.25984" id="153" name="minimum y" type="y-plane" />
+  <surface boundary="reflective" coeffs="1.25984" id="154" name="maximum y" type="y-plane" />
+  <surface boundary="reflective" coeffs="1.0" id="1370" name="Highest Extent" type="z-plane" />
+  <surface boundary="reflective" coeffs="-1.0" id="1380" name="Lowest Extent" type="z-plane" />
+
+</geometry>
diff --git a/tests/regression_tests/cmfd_feed_ng/materials.xml b/tests/regression_tests/cmfd_feed_ng/materials.xml
new file mode 100644
index 0000000000..bfa2d8842d
--- /dev/null
+++ b/tests/regression_tests/cmfd_feed_ng/materials.xml
@@ -0,0 +1,59 @@
+<?xml version='1.0' encoding='utf-8'?>
+<materials>
+  <material id="5" name="Helium">
+    <temperature>300</temperature>
+    <density units="g/cc" value="0.0015981" />
+    <nuclide name="He3" wo="1.5070346049256974e-06" />
+    <nuclide name="He4" wo="0.999998492965395" />
+  </material>
+  <material id="7" name="Zircaloy 4">
+    <temperature>300</temperature>
+    <density units="g/cc" value="6.55" />
+    <nuclide name="O16" wo="0.0012494965182849112" />
+    <nuclide name="O17" wo="5.034817150887735e-07" />
+    <nuclide name="Cr50" wo="4.1736864731106146e-05" />
+    <nuclide name="Cr52" wo="0.0008369936242576807" />
+    <nuclide name="Cr53" wo="9.673586881507429e-05" />
+    <nuclide name="Cr54" wo="2.4533642196138756e-05" />
+    <nuclide name="Fe54" wo="0.00011855672274761877" />
+    <nuclide name="Fe56" wo="0.001929932104229657" />
+    <nuclide name="Fe57" wo="4.536774095388075e-05" />
+    <nuclide name="Fe58" wo="6.143432068843669e-06" />
+    <nuclide name="Zr90" wo="0.49750307249921255" />
+    <nuclide name="Zr91" wo="0.10970127796055709" />
+    <nuclide name="Zr92" wo="0.16952409354767467" />
+    <nuclide name="Zr94" wo="0.17553856942304608" />
+    <nuclide name="Zr96" wo="0.02888298656950975" />
+    <nuclide name="Sn112" wo="0.0001325869644430062" />
+    <nuclide name="Sn114" wo="9.182449637587617e-05" />
+    <nuclide name="Sn115" wo="4.771905922545867e-05" />
+    <nuclide name="Sn116" wo="0.002058423153629443" />
+    <nuclide name="Sn117" wo="0.0010966473429083066" />
+    <nuclide name="Sn118" wo="0.0034879812938438245" />
+    <nuclide name="Sn119" wo="0.001247577110245757" />
+    <nuclide name="Sn120" wo="0.004771539495238715" />
+    <nuclide name="Sn122" wo="0.0006894094798456136" />
+    <nuclide name="Sn124" wo="0.000876291604244001" />
+  </material>
+  <material depletable="true" id="9" name="Fuel 1.6%">
+    <temperature>300</temperature>
+    <density units="g/cc" value="10.31341" />
+    <nuclide ao="1.9992419999999993" name="O16" />
+    <nuclide ao="0.0007579999999999998" name="O17" />
+    <nuclide ao="0.00014571996318473284" name="U234" />
+    <nuclide ao="0.01630316269333107" name="U235" />
+    <nuclide ao="0.983476441027697" name="U238" />
+    <nuclide ao="7.467631578722921e-05" name="U236" />
+  </material>
+  <material id="15" name="Borated Water">
+    <temperature>300</temperature>
+    <density units="g/cc" value="0.7405820675158279" />
+    <nuclide ao="0.00032178659941803253" name="B10" />
+    <nuclide ao="0.0013017583017829388" name="B11" />
+    <nuclide ao="1.996441935899364" name="H1" />
+    <nuclide ao="0.0003109742982341739" name="H2" />
+    <nuclide ao="0.9979980704223166" name="O16" />
+    <nuclide ao="0.0003783846764824448" name="O17" />
+    <sab name="c_H_in_H2O" />
+  </material>
+</materials>
diff --git a/tests/regression_tests/cmfd_feed_ng/results_true.dat b/tests/regression_tests/cmfd_feed_ng/results_true.dat
new file mode 100644
index 0000000000..fea3d38b8b
--- /dev/null
+++ b/tests/regression_tests/cmfd_feed_ng/results_true.dat
@@ -0,0 +1,621 @@
+k-combined:
+1.030507E+00 9.667655E-03
+tally 1:
+1.159445E+02
+1.344573E+03
+1.159285E+02
+1.344429E+03
+1.161340E+02
+1.349209E+03
+1.160434E+02
+1.347427E+03
+tally 2:
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+tally 3:
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+tally 5:
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+6.955922E+01
+cmfd indices
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+1.000000E+00
+3.000000E+00
+k cmfd
+1.024488E+00
+1.022339E+00
+1.024720E+00
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+1.022688E+00
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+1.026360E+00
+cmfd entropy
+1.999710E+00
+1.999709E+00
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+1.999747E+00
+1.999885E+00
+1.999911E+00
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+cmfd balance
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+3.401727E-04
+3.166255E-04
+2.642675E-04
+2.482640E-04
+cmfd dominance ratio
+ 3.737E-03
+ 3.786E-03
+ 3.798E-03
+ 3.789E-03
+ 3.741E-03
+ 3.772E-03
+ 3.793E-03
+ 3.684E-03
+ 3.740E-03
+ 3.764E-03
+ 3.798E-03
+cmfd openmc source comparison
+3.559244E-05
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+4.069206E-05
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+cmfd source
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diff --git a/tests/regression_tests/cmfd_feed_ng/settings.xml b/tests/regression_tests/cmfd_feed_ng/settings.xml
new file mode 100644
index 0000000000..9e483e6a09
--- /dev/null
+++ b/tests/regression_tests/cmfd_feed_ng/settings.xml
@@ -0,0 +1,25 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<settings>
+
+  <!-- Parameters for criticality calculation -->
+  <run_mode>eigenvalue</run_mode>
+  <batches>20</batches>
+  <inactive>10</inactive>
+  <particles>1000</particles>
+
+  <!-- Starting source -->
+  <source strength="1.0">
+    <space type="fission">
+      <parameters>-1.25984 -1.25984 -1 1.25984 1.25984 1</parameters>
+    </space>
+  </source>
+
+  <!-- Shannon Entropy -->
+  <mesh id="10">
+    <dimension> 2 2 1 </dimension>
+    <lower_left> -1.25984 -1.25984 -1.0 </lower_left>
+    <upper_right> 1.25984 1.25984 1.0 </upper_right>
+  </mesh>
+  <entropy_mesh>10</entropy_mesh>
+
+</settings>
diff --git a/tests/regression_tests/cmfd_feed_ng/tallies.xml b/tests/regression_tests/cmfd_feed_ng/tallies.xml
new file mode 100644
index 0000000000..477a078331
--- /dev/null
+++ b/tests/regression_tests/cmfd_feed_ng/tallies.xml
@@ -0,0 +1,21 @@
+<?xml version="1.0"?>
+<tallies>
+
+  <mesh id="1">
+    <type>regular</type>
+    <lower_left>-1.25984 -1.25984 -1.0 </lower_left>
+    <upper_right>1.25984 1.25984 1.0</upper_right>
+    <dimension>2 2 1</dimension>
+  </mesh>
+
+  <filter id="1">
+    <type>mesh</type>
+    <bins>1</bins>
+  </filter>
+
+  <tally id="1">
+    <filters>1</filters>
+    <scores>flux</scores>
+  </tally>
+
+</tallies>
diff --git a/tests/regression_tests/cmfd_feed_ng/test.py b/tests/regression_tests/cmfd_feed_ng/test.py
new file mode 100644
index 0000000000..e49f912aaa
--- /dev/null
+++ b/tests/regression_tests/cmfd_feed_ng/test.py
@@ -0,0 +1,47 @@
+from tests.testing_harness import CMFDTestHarness
+import openmc
+import numpy as np
+
+def test_cmfd_feed_ng():
+    """ Test n group CMFD solver with CMFD feedback"""
+    # Initialize and set CMFD mesh
+    cmfd_mesh = openmc.CMFDMesh()
+    cmfd_mesh.lower_left = -1.25984, -1.25984, -1.0
+    cmfd_mesh.upper_right = 1.25984, 1.25984, 1.0
+    cmfd_mesh.dimension = 2, 2, 1
+    cmfd_mesh.energy = [0.0, 0.625, 5.53080, 20000000]
+    cmfd_mesh.albedo = 1.0, 1.0, 1.0, 1.0, 1.0, 1.0
+
+    # Initialize and run CMFDRun object
+    cmfd_run = openmc.CMFDRun()
+    cmfd_run.mesh = cmfd_mesh
+    cmfd_run.reset = [5]
+    cmfd_run.begin = 10
+    cmfd_run.display = {'dominance': True}
+    cmfd_run.feedback = True
+    cmfd_run.downscatter = True
+    cmfd_run.gauss_seidel_tolerance = [1.e-15, 1.e-20]
+    cmfd_run.run()
+
+    # Create output string of all CMFD results to pass into testing harness
+    outstr = 'cmfd indices\n'
+    outstr += '\n'.join(['{0:12.6E}'.format(x) for x in cmfd_run._indices])
+    outstr += '\nk cmfd\n'
+    outstr += '\n'.join(['{0:12.6E}'.format(x) for x in cmfd_run._k_cmfd])
+    outstr += '\ncmfd entropy\n'
+    outstr += '\n'.join(['{0:12.6E}'.format(x) for x in cmfd_run._entropy])
+    outstr += '\ncmfd balance\n'
+    outstr += '\n'.join(['{0:12.6E}'.format(x) for x in cmfd_run._balance])
+    outstr += '\ncmfd dominance ratio\n'
+    outstr += '\n'.join(['{0:10.3E}'.format(x) for x in cmfd_run._dom])
+    outstr += '\ncmfd openmc source comparison\n'
+    outstr += '\n'.join(['{0:12.6E}'.format(x) for x in cmfd_run._src_cmp])
+    outstr += '\ncmfd source\n'
+    cmfdsrc = np.reshape(cmfd_run._cmfd_src, np.product(cmfd_run._indices),
+                         order='F')
+    outstr += '\n'.join(['{0:12.6E}'.format(x) for x in cmfdsrc])
+    outstr += '\n'
+
+    # Initialize and run CMFD test harness
+    harness = CMFDTestHarness('statepoint.20.h5', cmfd_results=outstr)
+    harness.main()
diff --git a/tests/regression_tests/cmfd_nofeed/test.py b/tests/regression_tests/cmfd_nofeed/test.py
index 4e34029a9e..11f8187659 100644
--- a/tests/regression_tests/cmfd_nofeed/test.py
+++ b/tests/regression_tests/cmfd_nofeed/test.py
@@ -2,7 +2,9 @@ from tests.testing_harness import CMFDTestHarness
 import openmc
 import numpy as np
 
+
 def test_cmfd_nofeed():
+    """ Test 1 group CMFD solver without CMFD feedback"""
     # Initialize and set CMFD mesh
     cmfd_mesh = openmc.CMFDMesh()
     cmfd_mesh.lower_left = -10.0, -1.0, -1.0
@@ -12,28 +14,28 @@ def test_cmfd_nofeed():
 
     # Initialize and run CMFDRun object
     cmfd_run = openmc.CMFDRun()
-    cmfd_run.cmfd_mesh = cmfd_mesh
-    cmfd_run.cmfd_begin = 5
-    cmfd_run.cmfd_display = 'dominance'
-    cmfd_run.cmfd_feedback = False
+    cmfd_run.mesh = cmfd_mesh
+    cmfd_run.begin = 5
+    cmfd_run.display = {'dominance': True}
+    cmfd_run.feedback = False
     cmfd_run.gauss_seidel_tolerance = [1.e-15, 1.e-20]
     cmfd_run.run()
 
     # Create output string of all CMFD results to pass into testing harness
     outstr = 'cmfd indices\n'
-    outstr += '\n'.join(['{0:12.6E}'.format(x) for x in cmfd_run._indices])
+    outstr += '\n'.join(['{0:12.6E}'.format(x) for x in cmfd_run.indices])
     outstr += '\nk cmfd\n'
-    outstr += '\n'.join(['{0:12.6E}'.format(x) for x in cmfd_run._k_cmfd])
+    outstr += '\n'.join(['{0:12.6E}'.format(x) for x in cmfd_run.k_cmfd])
     outstr += '\ncmfd entropy\n'
-    outstr += '\n'.join(['{0:12.6E}'.format(x) for x in cmfd_run._entropy])
+    outstr += '\n'.join(['{0:12.6E}'.format(x) for x in cmfd_run.entropy])
     outstr += '\ncmfd balance\n'
-    outstr += '\n'.join(['{0:12.6E}'.format(x) for x in cmfd_run._balance])
+    outstr += '\n'.join(['{0:12.6E}'.format(x) for x in cmfd_run.balance])
     outstr += '\ncmfd dominance ratio\n'
-    outstr += '\n'.join(['{0:10.3E}'.format(x) for x in cmfd_run._dom])
+    outstr += '\n'.join(['{0:10.3E}'.format(x) for x in cmfd_run.dom])
     outstr += '\ncmfd openmc source comparison\n'
-    outstr += '\n'.join(['{0:12.6E}'.format(x) for x in cmfd_run._src_cmp])
+    outstr += '\n'.join(['{0:12.6E}'.format(x) for x in cmfd_run.src_cmp])
     outstr += '\ncmfd source\n'
-    cmfdsrc = np.reshape(cmfd_run._cmfd_src, np.product(cmfd_run._indices),
+    cmfdsrc = np.reshape(cmfd_run.cmfd_src, np.product(cmfd_run.indices),
                          order='F')
     outstr += '\n'.join(['{0:12.6E}'.format(x) for x in cmfdsrc])
     outstr += '\n'
diff --git a/tests/testing_harness.py b/tests/testing_harness.py
index 50f02ee63c..408ddf1878 100644
--- a/tests/testing_harness.py
+++ b/tests/testing_harness.py
@@ -165,6 +165,15 @@ class CMFDTestHarness(TestHarness):
         finally:
             self._cleanup()
 
+    def _cleanup(self):
+        """Delete output files for numpy matrices and flux vectors."""
+        super()._cleanup()
+        output = ['loss.npz', 'loss.dat', 'prod.npz', 'prod.dat',
+                  'fluxvec.npy', 'fluxvec.dat']
+        for f in output:
+            if os.path.exists(f):
+                os.remove(f)
+
 
 class ParticleRestartTestHarness(TestHarness):
     """Specialized TestHarness for running OpenMC particle restart tests."""