The Z-factor
Z(p, T) correlations for fluid mixtures provide fast computational procedures using the fluid mixture properties rather than multi-component procedures of Equation of State.
These correlations are usually modelled through the pseudo-reduced fluid properties
(T_{pr}, p_{pr}):
T_{pr} = T/T_{pc} | Pseudo-reduced temperature | T_{pc} | Pseudo-critical temperature |
p_{pr} = p/p_{pc} | Pseudo-reduced pressure | p_{pc} | Pseudo-critical pressure |
Charts
Implicit Correlations
Hall and Yarborough’s correlation (Trube 1957) Dranchuk, Purvis and Robinson’s Correlation (Dranchuket al. 1971) Dranchuk and Abou-Kassem’s correlation (Abou-kassemand Dranchuk 1975) |
These correlations are quite accurate but computationally expensive and have problem with convergence when approaching the critical temperature.
Explicit Correlations
Sanjari and Nemati’s Correlation (2012) Azizi, Behbahani and Isazadeh’s Correlation (2010) Heidaryan, Moghdasi and Rahimi’s Correlation (2010) |
The explicit correlations do not have a convergence issues.
See also
Natural Science / Physics /Thermodynamics / Equation of State / Z-factor