Complementarity-based VLE formulation

idaes/core/base/components.py

@@ -228,6 +228,8 @@ def build(self):
             "omega": pyunits.dimensionless,
             "pressure_crit": base_units.PRESSURE,
             "temperature_crit": base_units.TEMPERATURE,
+            "volume_crit": base_units.VOLUME_MOL,
+            "compress_factor_crit": pyunits.dimensionless,
         }
         for p, u in var_dict.items():
             if p in self.config.parameter_data:

idaes/core/base/property_meta.py

@@ -324,6 +324,14 @@ def MOLALITY(self):
     def MOLECULAR_WEIGHT(self):
         return self._mass / self._amount
 
+    @property
+    def VOLUME_MOL(self):
+        return self._length**3 / self._amount
+
+    @property
+    def VOLUME_MASS(self):
+        return self._length**3 / self._mass
+
     # Energy
     @property
     def ENERGY(self):

idaes/core/base/tests/test_property_meta.py

@@ -186,6 +186,8 @@ def test_luminous_intensity(unit_set):
     "density_mass": (units.kg * units.m**-3),
     "density_mole": (units.mol * units.m**-3),
     "molecular_weight": (units.kg / units.mol),
+    "volume_mol": (units.m**3 / units.mol),
+    "volume_mass": (units.m**3 / units.kg),
     "energy": (units.kg * units.m**2 * units.s**-2),
     "energy_mass": (units.m**2 * units.s**-2),
     "energy_mole": (units.kg * units.m**2 * units.s**-2 * units.mol**-1),

idaes/core/util/phase_equilibria.py

@@ -26,6 +26,7 @@
 )
 import idaes.logger as idaeslog
 from idaes.core.solvers import get_solver
+from idaes.core.util.exceptions import PropertyNotSupportedError
 
 import idaes.logger as idaeslog
 
@@ -134,6 +135,26 @@ def Txy_data(
 
     model.props = model.params.build_state_block([1], defined_state=True)
 
+    # Check tbub etc
+    property_exists = False
+    try:
+        if hasattr(model.props[1], "temperature_bubble"):
+            property_exists = True
+    except PropertyNotSupportedError:
+        pass
+
+    try:
+        if hasattr(model.props[1], "temperature_dew"):
+            property_exists = True
+    except PropertyNotSupportedError:
+        pass
+
+    if not property_exists:
+        raise PropertyNotSupportedError(
+            "Txy_data require property package to support bubble and/or "
+            "dew point calculations."
+        )
+
     # Set intial concentration of component 1 close to 1
     x = 0.99
 
@@ -169,12 +190,14 @@ def Txy_data(
     Punit = pyunits.get_units(model.props[1].pressure)
     Tunit = pyunits.get_units(model.props[1].temperature)
 
+    # import pdb; pdb.set_trace()
     count = 1
     # Create and run loop to calculate temperatures at every composition
     for i in range(len(x_d)):
         model.props[1].mole_frac_comp[component_1].fix(x_d[i])
         model.props[1].mole_frac_comp[component_2].fix(1 - x_d[i] - xs)
         # solve the model
+        model.display()
         status = solver.solve(model, tee=False)
         # If solution is optimal store the concentration, and calculated temperatures in the created arrays
         if check_optimal_termination(status):
@@ -183,17 +206,17 @@ def Txy_data(
                 "Case: ", count, " Optimal. ", component_1, "x = {:.2f}".format(x_d[i])
             )
 
-            if hasattr(model.props[1], "_mole_frac_tdew") and hasattr(
-                model.props[1], "_mole_frac_tbub"
+            if hasattr(model.props[1], "temperature_dew") and hasattr(
+                model.props[1], "temperature_bubble"
             ):
                 Tbubb.append(value(model.props[1].temperature_bubble["Vap", "Liq"]))
                 Tdew.append(value(model.props[1].temperature_dew["Vap", "Liq"]))
 
-            elif hasattr(model.props[1], "_mole_frac_tdew"):
+            elif hasattr(model.props[1], "temperature_dew"):
                 print("One of the components only exists in vapor phase.")
                 Tdew.append(value(model.props[1].temperature_dew["Vap", "Liq"]))
 
-            elif hasattr(model.props[1], "_mole_frac_tbub"):
+            elif hasattr(model.props[1], "temperature_bubble"):
                 print("One of the components only exists in liquid phase.")
                 Tbubb.append(value(model.props[1].temperature_bubble["Vap", "Liq"]))