Patched SRT form of force models

lbmpy/forcemodels.py

@@ -240,9 +240,16 @@ class Guo(AbstractForceModel):
     """
 
     def __call__(self, lb_method):
-        force_terms = self.moment_space_forcing(lb_method)
-        result = lb_method.moment_matrix.inv() * force_terms
-        return result.expand()
+        if len(set(lb_method.relaxation_rates)) == 1:
+            #   It's an SRT method!
+            rr = lb_method.symbolic_relaxation_matrix[0]
+            force_terms = Luo(self.symbolic_force_vector)(lb_method)
+            correction_factor = (1 - rr / 2)
+            result = correction_factor * force_terms
+        else:
+            force_terms = self.moment_space_forcing(lb_method)
+            result = (lb_method.moment_matrix.inv() * force_terms).expand()
+        return result
 
     def moment_space_forcing(self, lb_method):
         luo = Luo(self.symbolic_force_vector)
@@ -270,12 +277,11 @@ class He(AbstractForceModel):
     Adapts the calculation of the macroscopic velocity as well as the equilibrium velocity
     (both shifted by :math:`\frac{\mathbf{F}}{2}`)!
 
-    Force moments are by default derived from the continuous maxwellian equilibrium
-    (to disable this, set ``use_continuous_maxwellian=False`` in constructor). From the
+    Force moments are derived from the continuous maxwellian equilibrium. From the
     moment integrals of the continuous force term
-    
+
     .. math::
-        
+
         F (\mathbf{c}) 
         = \frac{1}{\rho c_s^2} 
           \mathbf{F} \cdot ( \mathbf{c} - \mathbf{u} ) 
@@ -294,9 +300,8 @@ class He(AbstractForceModel):
             \right)
     """
 
-    def __init__(self, force, use_continuous_maxwellian=True):
+    def __init__(self, force):
         super(He, self).__init__(force)
-        self.continuous = use_continuous_maxwellian
 
     def forcing_terms(self, lb_method):
         rho = lb_method.zeroth_order_equilibrium_moment_symbol
@@ -314,7 +319,7 @@ class He(AbstractForceModel):
             eu_dot_f = (direction - u).dot(force)
             result.append(eq * eu_dot_f / cs_sq)
 
-        return result
+        return sp.Matrix(result)
 
     def continuous_force_raw_moments(self, lb_method):
         rho = lb_method.zeroth_order_equilibrium_moment_symbol
@@ -353,35 +358,26 @@ class He(AbstractForceModel):
         return (shift_matrix * raw_moments).expand()
 
     def __call__(self, lb_method):
-        force_terms = self.moment_space_forcing(lb_method)
-        result = lb_method.moment_matrix.inv() * force_terms
-        return result.expand()
+        if len(set(lb_method.relaxation_rates)) == 1:
+            #   It's an SRT method!
+            rr = lb_method.symbolic_relaxation_matrix[0]
+            force_terms = self.forcing_terms(lb_method)
+            correction_factor = (1 - rr / 2)
+            result = correction_factor * force_terms
+        else:
+            force_terms = self.moment_space_forcing(lb_method)
+            result = (lb_method.moment_matrix.inv() * force_terms).expand()
+        return result
 
     def moment_space_forcing(self, lb_method):
         correction_factor = sp.eye(len(lb_method.stencil)) - sp.Rational(1, 2) * lb_method.symbolic_relaxation_matrix
-
-        if self.continuous:
-            moments = self.continuous_force_raw_moments(lb_method)
-        else:
-            fq = self.forcing_terms(lb_method)
-            # u = lb_method.first_order_equilibrium_moment_symbols
-            moments = lb_method.moment_matrix * sp.Matrix(fq)
-            # reduced_moments = [remove_higher_order_terms(moment, order=2, symbols=u) for moment in moments]
-
+        moments = self.continuous_force_raw_moments(lb_method)
         moments = (correction_factor * moments).expand()
         return moments
 
     def central_moment_space_forcing(self, lb_method):
         correction_factor = sp.eye(len(lb_method.stencil)) - sp.Rational(1, 2) * lb_method.symbolic_relaxation_matrix
-
-        if self.continuous:
-            central_moments = self.continuous_force_central_moments(lb_method)
-        else:
-            fq = self.forcing_terms(lb_method)
-            # u = lb_method.first_order_equilibrium_moment_symbols
-            central_moments = lb_method.moment_matrix * sp.Matrix(fq)
-            # reduced_central_moments = [remove_higher_order_terms(central_moment, order=2, symbols=u)
-            #                         for central_moment in central_moments]
+        central_moments = self.continuous_force_central_moments(lb_method)
         central_moments = (correction_factor * central_moments).expand()
         return central_moments
 
@@ -410,9 +406,16 @@ class Buick(AbstractForceModel):
     """
 
     def __call__(self, lb_method, **kwargs):
-        force_terms = self.moment_space_forcing(lb_method)
-        result = lb_method.moment_matrix.inv() * force_terms
-        return result.expand()
+        if len(set(lb_method.relaxation_rates)) == 1:
+            #   It's an SRT method!
+            rr = lb_method.symbolic_relaxation_matrix[0]
+            force_terms = Simple(self.symbolic_force_vector)(lb_method)
+            correction_factor = (1 - rr / 2)
+            result = correction_factor * force_terms
+        else:
+            force_terms = self.moment_space_forcing(lb_method)
+            result = (lb_method.moment_matrix.inv() * force_terms).expand()
+        return result
 
     def moment_space_forcing(self, lb_method):
         simple = Simple(self.symbolic_force_vector)