add dippr107

HugoMVale · Oct 13, 2023 · 4b9589c · 4b9589c
1 parent 1c70d26
commit 4b9589c
Show file tree

Hide file tree

Showing 2 changed files with 78 additions and 4 deletions.
diff --git a/src/polykin/physprops/dippr.py b/src/polykin/physprops/dippr.py
@@ -12,7 +12,8 @@
            'DIPPR102',
            'DIPPR104',
            'DIPPR105',
-           'DIPPR106']
+           'DIPPR106',
+           'DIPPR107']
 
 
 class DIPPR(PropertyEquationT):
@@ -454,3 +455,69 @@ def equation(T: FloatOrArray,
         r"""DIPPR-106 equation."""
         Tr = T/Tc
         return A*(1-Tr)**(B + Tr*(C + Tr*(D + E*Tr)))
+
+
+class DIPPR107(DIPPRP5):
+    r"""[DIPPR](https://de.wikipedia.org/wiki/DIPPR-Gleichungen)-107 equation.
+
+    This equation implements the following temperature dependence:
+
+    $$ Y=A+B\left[{\frac {C/T}{\sinh \left(C/T\right)}}\right]^2 + \\
+        D\left[{\frac {E/T}{\cosh \left(E/T\right)}}\right]^2 $$
+
+    where $A$ to $E$ are component-specific constants and $T$ is the absolute
+    temperature.
+
+    Parameters
+    ----------
+    A : float
+        Parameter of equation.
+    B : float
+        Parameter of equation.
+    C : float
+        Parameter of equation.
+    D : float
+        Parameter of equation.
+    E : float
+        Parameter of equation.
+    Tmin : float
+        Lower temperature bound.
+        Unit = K.
+    Tmax : float
+        Upper temperature bound.
+        Unit = K.
+    unit : str
+        Unit of output variable $Y$.
+    symbol : str
+        Symbol of output variable $Y$.
+    name : str
+        Name.
+    """
+
+    _punits = ('#', '#', 'K', '#', 'K')
+
+    def __init__(self,
+                 A: float,
+                 B: float,
+                 C: float,
+                 D: float,
+                 E: float,
+                 Tmin: float = 0.0,
+                 Tmax: float = np.inf,
+                 unit: str = '-',
+                 symbol: str = 'Y',
+                 name: str = ''
+                 ) -> None:
+
+        super().__init__(A, B, C, D, E, Tmin, Tmax, unit, symbol, name)
+
+    @staticmethod
+    def equation(T: FloatOrArray,
+                 A: float,
+                 B: float,
+                 C: float,
+                 D: float,
+                 E: float
+                 ) -> FloatOrArray:
+        r"""DIPPR-107 equation."""
+        return A + B*(C/T/np.sinh(C/T))**2 + D*(E/T/np.cosh(E/T))**2
diff --git a/tests/physprops/test_equations.py b/tests/physprops/test_equations.py
@@ -3,7 +3,7 @@
 # Copyright Hugo Vale 2023
 
 from polykin.physprops.dippr import \
-    DIPPR100, DIPPR101, DIPPR102, DIPPR104, DIPPR105, DIPPR106
+    DIPPR100, DIPPR101, DIPPR102, DIPPR104, DIPPR105, DIPPR106, DIPPR107
 from polykin.physprops import Antoine, Wagner
 from polykin import plotequations
 
@@ -21,7 +21,7 @@ def test_DIPPR100():
 
 def test_DIPPR101():
     "P* of water"
-    p = DIPPR101(73.649, -7258.2, -7.3037, 4.1653E-6, 2.)
+    p = DIPPR101(73.649, -7258.2, -7.3037, 4.1653E-6, 2., unit='Pa')
     assert np.isclose(p(100., 'C'), 101325., rtol=1e-3)
 
 
@@ -39,7 +39,7 @@ def test_DIPPR104():
 
 def test_DIPPR105():
     "rhoL of water"
-    p = DIPPR105(0.14395, 0.0112, 649.727, 0.05107)
+    p = DIPPR105(0.14395, 0.0112, 649.727, 0.05107, unit='kg/m³')
     assert np.isclose(p(25., 'C'), 998., rtol=1e-3)
 
 
@@ -48,6 +48,13 @@ def test_DIPPR106():
     p = DIPPR106(647.096, 56600000., 0.612041, -0.625697, 0.398804)
     assert np.isclose(p(273.16, 'K'), 4.498084e7, rtol=1e-6)
 
+
+def test_DIPPR107():
+    "CpG of water"
+    p = DIPPR107(33363., 26790., 2610.5, 8896., 1169., Tmin=100.,
+                 Tmax=2273., unit='J/kmol.K')
+    assert np.isclose(p(300., 'K'), 33585.904, rtol=1e-6)
+
 # %% Vapor pressure equations