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11.2: Comparative Assessment of RK, SRK, and PR EOS

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    Over the years, these EOS have been tested, and some comparisons can be made. As an engineer, you have to be able to decide which EOS best fits your purposes.

    Redlich Kwong EOS:

    • Generally good for gas phase properties.
    • Poor for liquid phase properties.
    • Better when used in conjunction with a correlation for liquid phase behavior.
    • Satisfactory for gas phase fugacity calculation @ \(P_r < T_r/3\).
    • Satisfactory for enthalpy departure and entropy departure calculations.

    Soave Redlich Kwong & Peng Robinson EOS

    • Serve similar functions as the Redlich Kwong EOS but require more parameters.
    • PR obtains better liquid densities than SRK.
    • Overall, PR does a better job (slightly) for gas and condensate systems than SRK. However, for polar systems, SRK always makes a better prediction, but in the petroleum engineering business we do not usually deal with those.

    Contributors and Attributions

    • Prof. Michael Adewumi (The Pennsylvania State University). Some or all of the content of this module was taken from Penn State's College of Earth and Mineral Sciences' OER Initiative.

    This page titled 11.2: Comparative Assessment of RK, SRK, and PR EOS is shared under a CC BY-NC-SA 4.0 license and was authored, remixed, and/or curated by Michael Adewumi (John A. Dutton: e-Education Institute) via source content that was edited to the style and standards of the LibreTexts platform; a detailed edit history is available upon request.