Twenty‐one new theoretically based cubic equations of state for athermal hard‐sphere chain pure fluids and mixtures

Eight new hard‐sphere equations of state (EOS's) were obtained from molecular simulation data for the pair correlation function g HS (σ) vs. packing fraction η and combined with three theoretical schemes to obtain 21 new cubic EOS's for athermal hard‐sphere chains (AHSC's). The eight new hard‐sphere EOS models successfully reproduced isotropic fluid compressibility factor Z HS and g HS (σ) vs. η simulation data and predicted metastable liquid Z HS vs. η and virial coefficients up through B 10 . Moreover, calculated Z vs. η and reduced second‐virial coefficient vs. chain length m were compared with molecular simulation data for chains up to m = 201 for a set of representative (eight of twenty‐one) chain equations. Z vs. η for three AHSC binary mixtures was also successfully predicted. The results indicate that the new cubic EOS's give a satisfactory representation of simulation data for chain fluids and can be used to develop theoretically based cubic EOS's for “real” fluids including attractive effects. © 2015 American Institute of Chemical Engineers AIChE J, 61: 1677–1690, 2015