I am comparing different methods available in Prode library
ISO 18453
CPA
Extended Peng Robinson
Extended Soave Redlich Kwong
GERG (2008)
with published data (Data and prediction of water content of high pressure nitrogen methane and natural gas Fluid Phase Equilibria, 2007, GPSA data, and others),
my understanding is that complex models as CPA or GERG may not offer significant advantages for VLE of mixtures of HC (mostly methane) + N2 and water over extended EOS as ISO (18453) or the Peng Robinson / Soave with temperature dependent BIPs available in ISO and Prode,
is that true ?
For which natural gas mixtures (or applications) should I use CPA models which are recommended by many authors ?