Fix exergy implementation

src/tespy/connections/connection.py

@@ -952,14 +952,17 @@ def get_physical_exergy(self, pamb, Tamb):
                 E^\mathrm{M} = \dot{m} \cdot e^\mathrm{M}\\
                 E^\mathrm{PH} = \dot{m} \cdot e^\mathrm{PH}
         """
-        self.ex_therm, self.ex_mech = fp.calc_physical_exergy(self, p0, T0)
+        self.ex_therm, self.ex_mech = fp.functions.calc_physical_exergy(
+            self.h.val_SI, self.s.val_SI, self.p.val_SI, pamb, Tamb,
+            self.fluid_data, self.mixing_rule, self.T.val_SI
+        )
         self.Ex_therm = self.ex_therm * self.m.val_SI
         self.Ex_mech = self.ex_mech * self.m.val_SI
 
         self.ex_physical = self.ex_therm + self.ex_mech
         self.Ex_physical = self.m.val_SI * self.ex_physical
 
-    def get_chemical_exergy(self, p0, T0, Chem_Ex):
+    def get_chemical_exergy(self, pamb, Tamb, Chem_Ex):
         r"""
         Get the value of a connection's specific chemical exergy.
 
@@ -983,7 +986,10 @@ def get_chemical_exergy(self, p0, T0, Chem_Ex):
         if Chem_Ex is None:
             self.ex_chemical = 0
         else:
-            self.ex_chemical = fp.calc_chemical_exergy(self, p0, T0, Chem_Ex)
+            self.ex_chemical = fp.functions.calc_chemical_exergy(
+                pamb, Tamb, self.fluid_data, Chem_Ex, self.mixing_rule,
+                self.T.val_SI
+            )
 
         self.Ex_chemical = self.m.val_SI * self.ex_chemical
 

src/tespy/tools/fluid_properties/functions.py

@@ -2,10 +2,11 @@
 from .helpers import get_pure_fluid
 from .helpers import get_number_of_fluids
 from .helpers import inverse_temperature_mixture
-from .mixtures import T_MIX_PH_REVERSE
-from .mixtures import T_MIX_PS_REVERSE
+from .mixtures import EXERGY_CHEMICAL
 from .mixtures import H_MIX_PT_DIRECT
 from .mixtures import S_MIX_PT_DIRECT
+from .mixtures import T_MIX_PH_REVERSE
+from .mixtures import T_MIX_PS_REVERSE
 from .mixtures import V_MIX_PT_DIRECT
 from .mixtures import VISCOSITY_MIX_PT_DIRECT
 
@@ -20,6 +21,57 @@ def isentropic(p_1, h_1, p_2, fluid_data, mixing_rule=None, T0=None):
         return h_mix_pT(p_2, T_2, fluid_data, mixing_rule)
 
 
+def calc_physical_exergy(h, s, p, pamb, Tamb, fluid_data, mixing_rule=None, T0=None):
+    r"""
+    Calculate specific physical exergy.
+
+    Physical exergy is allocated to a thermal and a mechanical share according
+    to :cite:`Morosuk2019`.
+
+    Parameters
+    ----------
+    pamb : float
+        Ambient pressure p0 / Pa.
+
+    Tamb : float
+        Ambient temperature T0 / K.
+
+    Returns
+    -------
+    e_ph : tuple
+        Specific thermal and mechanical exergy
+        (:math:`e^\mathrm{T}`, :math:`e^\mathrm{M}`) in J / kg.
+
+        .. math::
+
+            e^\mathrm{T} = \left( h - h \left( p, T_0 \right) \right) -
+            T_0 \cdot \left(s - s\left(p, T_0\right)\right)
+
+            e^\mathrm{M}=\left(h\left(p,T_0\right)-h\left(p_0,T_0\right)\right)
+            -T_0\cdot\left(s\left(p, T_0\right)-s\left(p_0,T_0\right)\right)
+
+            e^\mathrm{PH} = e^\mathrm{T} + e^\mathrm{M}
+    """
+    h_T0_p = h_mix_pT(p, Tamb, fluid_data, mixing_rule)
+    s_T0_p = s_mix_pT(p, Tamb, fluid_data, mixing_rule)
+    ex_therm = (h - h_T0_p) - T0 * (s - s_T0_p)
+    h0 = h_mix_pT(pamb, Tamb, fluid_data, mixing_rule)
+    s0 = s_mix_pT(pamb, Tamb, fluid_data, mixing_rule)
+    ex_mech = (h_T0_p - h0) - T0 * (s_T0_p - s0)
+    return ex_therm, ex_mech
+
+
+def calc_chemical_exergy(pamb, Tamb, fluid_data, Chem_Ex, mixing_rule=None, T0=None):
+    if get_number_of_fluids(fluid_data) == 1:
+        pure_fluid = get_pure_fluid(fluid_data)
+        fluid_aliases = pure_fluid["wrapper"]._aliases
+        y = [Chem_Ex[k][Chem_Ex[k][4]] for k in fluid_aliases if k in Chem_Ex]
+        return y[0] / pure_fluid["wrapper"]._molar_mass * 1e3
+    else:
+        _check_mixing_rule(mixing_rule, EXERGY_CHEMICAL, "chemical exergy")
+        return EXERGY_CHEMICAL[mixing_rule](pamb, Tamb, fluid_data, Chem_Ex)
+
+
 def T_mix_ph(p, h, fluid_data, mixing_rule=None, T0=None):
     if get_number_of_fluids(fluid_data) == 1:
         pure_fluid = get_pure_fluid(fluid_data)

src/tespy/tools/fluid_properties/mixtures.py

@@ -1,11 +1,12 @@
 import CoolProp as CP
+import numpy as np
 
+from tespy.tools.global_vars import gas_constants
 from .helpers import _is_larger_than_precision
 from .helpers import calc_molar_mass_mixture
 from .helpers import get_molar_fractions
 
 
-
 def h_mix_pT_ideal(p=None, T=None, fluid_data=None, **kwargs):
     molar_fractions = get_molar_fractions(fluid_data)
 
@@ -49,12 +50,9 @@ def h_mix_pT_forced_gas(p, T, fluid_data, **kwargs):
 
         if _is_larger_than_precision(data["mass_fraction"]):
             pp = p * molar_fractions[fluid]
-            if fluid == "H2O":
-                if pp >= data["wrapper"]._p_min:
-                    if T <= data["wrapper"].T_sat(pp):
-                        h += data["wrapper"].h_QT(1, T) * data["mass_fraction"]
-                    else:
-                        h += data["wrapper"].h_pT(pp, T) * data["mass_fraction"]
+            if fluid == "H2O" and pp >= data["wrapper"]._p_min:
+                if T <= data["wrapper"].T_sat(pp):
+                    h += data["wrapper"].h_QT(1, T) * data["mass_fraction"]
                 else:
                     h += data["wrapper"].h_pT(pp, T) * data["mass_fraction"]
             else:
@@ -220,6 +218,44 @@ def viscosity_mix_pT_incompressible(p=None, T=None, fluid_data=None, **kwargs):
     return viscosity
 
 
+def exergy_chemical_ideal_cond(pamb, Tamb, fluid_data, Chem_Ex):
+
+    molar_fractions = get_molar_fractions(fluid_data)
+    water_alias = _water_in_mixture(fluid_data)
+    if water_alias:
+        water_alias = next(iter(water_alias))
+        _, molar_fractions_gas, _, molar_liquid = cond_check(
+            pamb, Tamb, fluid_data, water_alias
+        )
+    else:
+        molar_fractions_gas = molar_fractions
+        molar_liquid = 0
+
+    ex_cond = 0
+    ex_dry = 0
+    for fluid, x in molar_fractions_gas.items():
+        if x == 0:
+            continue
+
+        fluid_aliases = fluid_data[fluid]["wrapper"]._aliases
+
+        if molar_liquid > 0:
+            y = [
+                Chem_Ex[k][2] for k in fluid_aliases if k in Chem_Ex
+            ]
+            ex_cond += molar_liquid * y[0]
+
+        y = [Chem_Ex[k][3] for k in fluid_aliases if k in Chem_Ex]
+        ex_dry += x * y[0] + Tamb * gas_constants['uni'] * 1e-3 * x * np.log(x)
+
+    ex_chemical = ex_cond + ex_dry * (1 - molar_liquid)
+    ex_chemical *= 1 / calc_molar_mass_mixture(
+        fluid_data, molar_fractions
+    )
+
+    return ex_chemical * 1e3  # Data from Chem_Ex are in kJ / mol
+
+
 def _water_in_mixture(fluid_data):
     water_aliases = set(CP.CoolProp.get_aliases("H2O"))
     return water_aliases & set([f for f in fluid_data if _is_larger_than_precision(fluid_data[f]["mass_fraction"])])
@@ -324,3 +360,7 @@ def cond_check(p, T, fluid_data, water_alias):
     "ideal-cond": viscosity_mix_pT_ideal,
     "incompressible": viscosity_mix_pT_incompressible
 }
+
+EXERGY_CHEMICAL = {
+    "ideal-cond": exergy_chemical_ideal_cond,
+}

src/tespy/tools/fluid_properties/wrappers.py

@@ -77,6 +77,7 @@ def __init__(self, fluid, back_end=None) -> None:
     def _set_constants(self):
         self._T_min = self.AS.trivial_keyed_output(CP.iT_min)
         self._T_max = self.AS.trivial_keyed_output(CP.iT_max)
+        self._aliases = CP.CoolProp.get_aliases(self.fluid)
 
         if self.back_end == "INCOMP":
             self._p_min = 1e2