Make kappa-fission mandatory again.

Author: nuclearkevin

docs/source/usersguide/random_ray.rst

@@ -646,8 +646,7 @@ model to use these multigroup cross sections. An example is given below::
       overwrite_mgxs_library=False,
       mgxs_path="mgxs.h5",
       correction=None,
-      source_energy=None,
-      gen_kappa_fission=True
+      source_energy=None
   )
 
 The most important parameter to set is the ``method`` parameter, which can be

openmc/model/model.py

@@ -1778,7 +1778,6 @@ def _generate_infinite_medium_mgxs(
         correction: str | None,
         directory: PathLike,
         source_energy: openmc.stats.Univariate | None = None,
-        gen_kappa_fission: bool = False,
     ):
         """Generate a MGXS library by running multiple OpenMC simulations, each
         representing an infinite medium simulation of a single isolated
@@ -1817,9 +1816,6 @@ def _generate_infinite_medium_mgxs(
         source_energy : openmc.stats.Univariate, optional
             Energy distribution to use when generating MGXS data, replacing any
             existing sources in the model.
-        gen_kappa_fission : bool, optional
-            Whether fission heating cross sections (kappa-fission) should be
-            generated.
         """
         mgxs_sets = []
         for material in self.materials:
@@ -1866,18 +1862,16 @@ def _generate_infinite_medium_mgxs(
             if correction == 'P0':
                 mgxs_lib.mgxs_types = [
                     'nu-transport', 'absorption', 'nu-fission', 'fission',
-                    'consistent nu-scatter matrix', 'multiplicity matrix', 'chi'
+                    'consistent nu-scatter matrix', 'multiplicity matrix', 'chi',
+                    'kappa-fission'
                 ]
             elif correction is None:
                 mgxs_lib.mgxs_types = [
                     'total', 'absorption', 'nu-fission', 'fission',
-                    'consistent nu-scatter matrix', 'multiplicity matrix', 'chi'
+                    'consistent nu-scatter matrix', 'multiplicity matrix', 'chi',
+                    'kappa-fission'
                 ]
 
-            # Generate kappa-fission cross sections if requested
-            if gen_kappa_fission:
-                mgxs_lib.mgxs_types.append('kappa-fission')
-
             # Specify a "cell" domain type for the cross section tally filters
             mgxs_lib.domain_type = "material"
 
@@ -1995,7 +1989,6 @@ def _generate_stochastic_slab_mgxs(
         correction: str | None,
         directory: PathLike,
         source_energy: openmc.stats.Univariate | None = None,
-        gen_kappa_fission: bool = False,
     ) -> None:
         """Generate MGXS assuming a stochastic "sandwich" of materials in a layered
         slab geometry. While geometry-specific spatial shielding effects are not
@@ -2037,9 +2030,6 @@ def _generate_stochastic_slab_mgxs(
             no sources are defined on the model and the run mode is
             'eigenvalue', then a default Watt spectrum source (strength = 0.99)
             is added.
-        gen_kappa_fission : bool, optional
-            Whether fission heating cross sections (kappa-fission) should be
-            generated.
         """
         model = openmc.Model()
         model.materials = self.materials
@@ -2080,14 +2070,12 @@ def _generate_stochastic_slab_mgxs(
        # Specify needed cross sections for random ray
         if correction == 'P0':
             mgxs_lib.mgxs_types = ['nu-transport', 'absorption', 'nu-fission', 'fission',
-                                   'consistent nu-scatter matrix', 'multiplicity matrix', 'chi']
+                                   'consistent nu-scatter matrix', 'multiplicity matrix', 'chi',
+                                   'kappa-fission']
         elif correction is None:
             mgxs_lib.mgxs_types = ['total', 'absorption', 'nu-fission', 'fission',
-                                   'consistent nu-scatter matrix', 'multiplicity matrix', 'chi']
-
-        # Generate kappa-fission cross sections if requested
-        if gen_kappa_fission:
-            mgxs_lib.mgxs_types.append('kappa-fission')
+                                   'consistent nu-scatter matrix', 'multiplicity matrix', 'chi',
+                                   'kappa-fission']
 
         # Specify a "cell" domain type for the cross section tally filters
         mgxs_lib.domain_type = "material"
@@ -2127,7 +2115,6 @@ def _generate_material_wise_mgxs(
         mgxs_path: PathLike,
         correction: str | None,
         directory: PathLike,
-        gen_kappa_fission: bool = False,
     ) -> None:
         """Generate a material-wise MGXS library for the model by running the
         original continuous energy OpenMC simulation of the full material
@@ -2152,9 +2139,6 @@ def _generate_material_wise_mgxs(
             "P0".
         directory : PathLike
             Directory to run the simulation in, so as to contain XML files.
-        gen_kappa_fission : bool, optional
-            Whether fission heating cross sections (kappa-fission) should be
-            generated.
         """
         model = copy.deepcopy(self)
         model.tallies = openmc.Tallies()
@@ -2180,18 +2164,16 @@ def _generate_material_wise_mgxs(
         if correction == 'P0':
             mgxs_lib.mgxs_types = [
                 'nu-transport', 'absorption', 'nu-fission', 'fission',
-                'consistent nu-scatter matrix', 'multiplicity matrix', 'chi'
+                'consistent nu-scatter matrix', 'multiplicity matrix', 'chi',
+                'kappa-fission'
             ]
         elif correction is None:
             mgxs_lib.mgxs_types = [
                 'total', 'absorption', 'nu-fission', 'fission',
-                'consistent nu-scatter matrix', 'multiplicity matrix', 'chi'
+                'consistent nu-scatter matrix', 'multiplicity matrix', 'chi',
+                'kappa-fission'
             ]
 
-        # Generate kappa-fission cross sections if requested
-        if gen_kappa_fission:
-            mgxs_lib.mgxs_types.append('kappa-fission')
-
         # Specify a "cell" domain type for the cross section tally filters
         mgxs_lib.domain_type = "material"
 
@@ -2233,7 +2215,6 @@ def convert_to_multigroup(
         mgxs_path: PathLike = "mgxs.h5",
         correction: str | None = None,
         source_energy: openmc.stats.Univariate | None = None,
-        gen_kappa_fission: bool = False,
     ):
         """Convert all materials from continuous energy to multigroup.
 
@@ -2274,9 +2255,6 @@ def convert_to_multigroup(
             'eigenvalue', then a default Watt spectrum source (strength = 0.99)
             is added. Note that this argument is only used when using the
             "stochastic_slab" or "infinite_medium" MGXS generation methods.
-        gen_kappa_fission : bool, optional
-            Whether fission heating cross sections (kappa-fission) should be
-            generated.
         """
         if isinstance(groups, str):
             groups = openmc.mgxs.EnergyGroups(groups)
@@ -2306,15 +2284,13 @@ def convert_to_multigroup(
             if not Path(mgxs_path).is_file() or overwrite_mgxs_library:
                 if method == "infinite_medium":
                     self._generate_infinite_medium_mgxs(
-                        groups, nparticles, mgxs_path, correction, tmpdir, source_energy,
-                        gen_kappa_fission)
+                        groups, nparticles, mgxs_path, correction, tmpdir, source_energy)
                 elif method == "material_wise":
                     self._generate_material_wise_mgxs(
-                        groups, nparticles, mgxs_path, correction, tmpdir, gen_kappa_fission)
+                        groups, nparticles, mgxs_path, correction, tmpdir)
                 elif method == "stochastic_slab":
                     self._generate_stochastic_slab_mgxs(
-                        groups, nparticles, mgxs_path, correction, tmpdir, source_energy,
-                        gen_kappa_fission)
+                        groups, nparticles, mgxs_path, correction, tmpdir, source_energy)
                 else:
                     raise ValueError(
                         f'MGXS generation method "{method}" not recognized')

tests/regression_tests/random_ray_auto_convert_kappa_fission/test.py

@@ -28,8 +28,7 @@ def test_random_ray_auto_convert(method):
         # Convert to a multi-group model
         model.convert_to_multigroup(
             method=method, groups='CASMO-2', nparticles=100,
-            overwrite_mgxs_library=False, mgxs_path="mgxs.h5",
-            gen_kappa_fission=True
+            overwrite_mgxs_library=False, mgxs_path="mgxs.h5"
         )
 
         # Convert to a random ray model