Single Property Equations (Binary)
Single properties are represented either
Directly (e.g., heat capacity, viscosity, etc.) or as
Excess properties (e.g., excess volume, excess enthalpy, etc.).
In
TDE one equation formulation is used for each type of data representation.
General Property Ψ Representation
Ψ =
x1×Ψ1 +
x2×Ψ2 + Σa
i×x1×x2×(
x1 -
x2)
i, where
xj and
Ψj are the mole fraction and property value for component
j, and the summation is from
i = 0 to
nTerms.
Special Case 1: Viscosity
ln(
h/
ho) =
x1×ln{
h(1)/
ho } +
x2×ln{
h(2)/
ho} + Σ a
i×x1×x2×(
x1 -
x2)
i, where
ho = 1 Pa
×s and the summation is from
i = 0 to
nTerms.
Special Case 2: Density
r = (
x1×M1 +
x2×M2)/
Vm, where
Vm = x1×M1/r1 + x2×M2/r2 + Σ ai×x1×x2×(x1 - x2)i, where the summation is from i = 0 to nTerms.
r is density (kg×m-3), Vm is molar volume (mol×m-3), and M is the molar mass (kg×mol-1).
General Excess Property ΨEX Representation
ΨEX = Σ a
i×x1×x2×(
x1 -
x2)
i, where
xj is the mole fraction of component
j, and the summation is from
i = 0 to
nTerms.
The Vector ai is temperature dependent with 1 to 5 terms.