Calculation Of The Thermodynamic Properties Of Fluids By Using The First-Order Mean Spherical Approximation Equation Of State

Radial distribution functions (RDF), which are key functions for describing the structure of fluids, play an important role in determining equilibrium and non-equilibrium thermodynamic properties of fluids. The theory of RDF is one of the most active research aspects in chemical engineering thermodynamics and the most precise section among the theory of liquids as well. Tang's first-order mean spherical approximation (FMSA) equation of state (EOS) based on the theory of RDF is a totally theoretical EOS.The software, which is developed based on the FMSA theory, was used in this work to calculate the RDF, compressibility factors, phase coexistence diagram and isotherms for LJ fluid. The results were compared with the computer simulation data. It is shown that the FMSA theory can predict the structure of LJ fluid excellently. It is also shown that, except the critical region, the FMSA function can predict the phase diagram and PVT properties of LJ fluid perfectly. In addition, in the range of reduced temperature T~* from 1.0 to...