Thermodynamic properties of mixtures by the hard sphere expansion theory
Hsu, I-Chien Robert
Leland, Thomas W.
Master of Science
In this work, a procedure for computing the thermodynamic properties of a mixture of methane and ethane based on the Hard Sphere Expansion (HSE) theory of Mansoori and Leland is presented. A method for determining an effective hard sphere diameter which does not require knowledge of the intermolecular potential is formulated for use in describing the repulsive contribution. The terms attributed to the attractive part of the intermolecular potential are evaluated employing the corresponding states principle with methane as reference. Vennix-Kobayashi's equation of state is used for this purpose. Shape factors for calculating the HSE pseudo criticals have been defined. The hard sphere diameters calculated by the HSE method compare favorably with those reported by Hirschfelder-Curtiss-Bird using the Lennard-Jones model. Compressibility factors have also been computed and show good agreement with experimental data. In preparation for expending the method to the calculation of fugacities of components in the mixture, the hard sphere value for the fagacities was derived.