부산대학교 도서관

The Peng-Robinson (PR) EOS is a very successful two-parameter equation of state to estimate thermodynamicproperties of pure compounds as well as mixtures. The PR EOS has been modified and revised several ways toimprove estimates, and the most popular modification is for the attractive term through alpha function and temperaturedependent covolume parameter in the repulsive term. However, the unphysical, i.e., negative values of temperaturedependent co volume parameter at high temperature lead to undesirable results. We have addressed this issue inthe present work by incorporating a temperature dependent covolume parameter and yet physically consistent over alarge range of temperature. In the present work, the Modified-Peng-Robinson 2 (MPR2) equation of state is presentedby modifying the alpha function in attractive term and temperature dependent co-volume parameter in repulsive termof the PR EOS. The accuracy of MPR2 EOS is demonstrated by comparing results with the PR, HKM1, and MPR1equations of state. The thermodynamic properties, namely saturated vapor pressure and liquid density, enthalpy ofvaporization, compressed liquid densities in sub and supercritical region, heat capacities (isobaric and isochoric), andsound velocity of pure compounds, are predicted by MPR2 EOS which agrees very well with the experimental data. We have further studied 24 refrigerant properties like vapor and liquid densities. The work has also been extended tostudy the phase behavior of 26 binary mixtures using van der Waals single fluid mixing rules.