New Piecewise EOS for Compressibility Factor Prediction Based on the M-factor Theory

In this study for the first time a new description of compressibility factor is renderedbased on the virial expansion. the compressibility factor as a function of m-factor is qualitativelyand quantitatively expressed. at first, we present how may the third, fourth and higher order virialcoefficients be logically ignored in order to simplify the virial equation. the results show, whenthe compressibility factor is presented as a function of m-factor instead of pressure, an improvedregression operation on experimental data is possible. moreover, the results show thecompressibility factor will not depend on kind of substance, if it is considered as a function ofm-factor. also we found that the compressibility factor can easily be estimated by a second orderpolynomial in respect to m-factor or in more mature form at most by a third order polynomial.the simplifying effects of m-factor to present the compressibility factor of some binary mixturesare investigated. it was found that the classical mixing rules can never be applied for predictingthe compressibility factor under special conditions. also we affirm the distinct characteristics ofm-factor compared to its composer parameters, qualitatively. a quantitative study on m-factorproperties, which supplies a prolegomena to a new comprehensive equation of state,was accomplished as well. we find the favorable eos is a multi-domain function estimatingexperimental data with high accuracy.