A new equation of state for gaseous, liquid, and supercritical fluids

In the present study, a new equation of state (EOS) was derived by using the thermodynamic equation of state and the intermolecular potential (3, 9, 12). It was shown that the EOS is applicable in low and high ranges of temperature, pressure and density for gaseous, liquid and supercritical fluids and even in liquid–gas phase transition region. The new EOS is applicable for a variety of fluids such as polar, nonpolar, rare gases, short-chain and long-chain hydrocarbon fluids. The absolute percent deviation of the calculated density for gaseous, liquid and supercritical fluids is very low. The common bulk modulus point and the common compression point regularities were predicted by the new EOS. The new EOS was compared with some equations of state which had been derived similarly. It is shown that the repulsive potential used in the EOS derivation is effective in predicting correct fluid properties.