Finished Casson model

lbmpy/creationfunctions.py

@@ -226,11 +226,10 @@ class LBMConfig:
     set to Smagorinsky constant to activate turbulence model, ``omega_output_field`` can be set to
     write out adapted relaxation rates. If set to `True`, 0.12 is used as default smagorinsky constant.
     """
-    cassons: Union[dict, bool] = False
+    cassons: CassonsParameters = False
     """
     Adds the Cassons model according to https://doi.org/10.1007/s10955-005-8415-x
-    Set either to True, to obtain model with standard parameters or pass a dictionary containing
-    `yield_stress`, `omega_min` and `omega_max`
+    The parameters are set with the ``CassonsParameters`` dataclass.
     """
     fluctuating: dict = False
     """
@@ -656,11 +655,7 @@ def create_lb_collision_rule(lb_method=None, lbm_config=None, lbm_optimisation=N
             collision_rule.simplification_hints['split_groups'][0].append(sp.Symbol("smagorinsky_omega"))
 
     elif lbm_config.cassons:
-        if isinstance(lbm_config.cassons, CassonsParameters):
-            parameters = lbm_config.cassons
-        else:
-            parameters = CassonsParameters()
-        collision_rule = add_cassons_model(collision_rule, parameter=parameters,
+        collision_rule = add_cassons_model(collision_rule, parameter=lbm_config.cassons,
                                            omega_output_field=lbm_config.omega_output_field)
 
     if lbm_config.output: