Fix first test cases

lbmpy/boundaries/boundaryconditions.py

@@ -626,6 +626,8 @@ class DiffusionDirichlet(LbBoundary):
         return [LbmWeightInfo(lb_method, self._data_type)]
 
     def __call__(self, f_out, f_in, dir_symbol, inv_dir, lb_method, index_field):
+        assert lb_method.conserved_quantity_computation.zero_centered_pdfs is False, \
+            "DiffusionDirichlet only works for methods with normal pdfs storage -> set zero_centered=False"
         weight_info = LbmWeightInfo(lb_method, self._data_type)
         w_dir = weight_info.weight_of_direction(dir_symbol, lb_method)
         return [Assignment(f_in(inv_dir[dir_symbol]),

lbmpy_tests/test_chapman_enskog.py

@@ -38,7 +38,7 @@ def test_steady_state_silva_paper_comparison():
     eps, tau, lambda_plus, f = sp.symbols("epsilon tau Lambda f")
 
     lbm_config = LBMConfig(stencil=LBStencil(Stencil.D3Q19), compressible=False, relaxation_rate=1 / tau,
-                           continuous_equilibrium=False)
+                           continuous_equilibrium=False, zero_centered=False)
     method = create_lb_method(lbm_config=lbm_config)
     analysis = SteadyStateChapmanEnskogAnalysis(method)
 

lbmpy_tests/test_conserved_quantity_relaxation_invariance.py

@@ -9,7 +9,7 @@ import sympy as sp
 import math
 
 from lbmpy.enums import Stencil, Method
-from lbmpy.methods import RelaxationInfo, create_srt, create_trt, create_trt_kbc, \
+from lbmpy.methods import create_srt, create_trt, create_trt_kbc, \
     create_with_default_polynomial_cumulants
 from lbmpy.methods.momentbased.momentbasedmethod import MomentBasedLbMethod
 from lbmpy.methods.centeredcumulant.centeredcumulantmethod import CenteredCumulantBasedLbMethod
@@ -32,7 +32,8 @@ def __change_relaxation_rate_of_conserved_moments(method, new_relaxation_rate=sp
     elif isinstance(method, CenteredCumulantBasedLbMethod):
         changed_method = CenteredCumulantBasedLbMethod(method.stencil, method.equilibrium_distribution, rr_dict,
                                                        method.conserved_quantity_computation,
-                                                       force_model=method.force_model)
+                                                       force_model=method.force_model,
+                                                       zero_centered=True)
     else:
         raise ValueError("Not a moment or cumulant-based method")
 

lbmpy_tests/test_diffusion.py

@@ -103,6 +103,7 @@ def test_diffusion():
 
     # Lattice Boltzmann method
     lbm_config = LBMConfig(stencil=stencil, method=Method.MRT, relaxation_rates=[1, 1.5, 1, 1.5, 1],
+                           zero_centered=False,
                            velocity_input=vel_field, output={'density': con_field}, compressible=True,
                            weighted=True, kernel_type='stream_pull_collide')
 

lbmpy_tests/test_force.py

@@ -275,7 +275,7 @@ def test_modes_central_moment(force_model, compressible):
     F = list(sp.symbols(f"F_:{stencil.D}"))
 
     lbm_config = LBMConfig(method=Method.CENTRAL_MOMENT, stencil=stencil, relaxation_rate=omega_s,
-                           compressible=True, force_model=force_model, force=tuple(F))
+                           compressible=compressible, force_model=force_model, force=tuple(F))
     method = create_lb_method(lbm_config=lbm_config)
 
     subs_dict = method.subs_dict_relxation_rate