Crossover Carnhan starling equation of state

Accurate extrapolations of fluid phase behavior of pure fluids and mixtures, especially nearthe critical point, are very important for many process technologies and product design invarious industries. As commonly accepted, because of the asymptotic nature of singularbehavior of fluids in the immediate region of the critical point, the thermodynamic propertiesof different systems in the same universality class behave as 3D-Ising model. Hereupon,widely efforts have been made for the development of better thermodynamic representations,such as cubic equation of state. Despite of their simplicity of calculation and their remarkablepredictive capabilities over a wide range, these classical models did not gave very accurateprediction for the thermodynamics properties of fluids near the critical region.In this paper, we use a theoretical approach to correct Carnhan starling equation of state(EoS) for the effects of critical fluctuations. The approach utilizes a transformation deducedfrom the renormalization-group theory (RGT) of critical phenomena that was developedearlier for a classical Landau expansion of Helmholtz free energy density and successfullyuse with Kostrowicka Wyczalkowska et al. [1] to show how critical fluctuations effectedthermodynamic properties predicted with Vander Waals equation.