Abstract A four parameter cubic equation of state, GDN-CEOS, is presented to describe thermodynamic properties of pure fluids and mixtures. We have cast three of the four parameters in terms of the remaining parameter and all the parameters are temperature independent. A new alpha function is proposed in the attractive term of the CEOS; which requires two compound-specific parameters determined from saturation vapor pressure data at two reduced temperature points T r = 0.5 and 0.7. Hence, the GDN CEOS has five inputs per substance: the critical temperature (Tc), the critical pressure (Pc), the critical compressibility factor (Zc) and two compound specific parameters (m, n) of the alpha function. The saturated vapor pressure and liquid density of 334 pure compounds, representing a large variety of functional groups, are predicted successfully. Other thermodynamic properties such as isobaric and isochoric heat capacities, sound velocity, compressed liquid density and enthalpy of vaporization have been calculated using GDN CEOS with remarkably good accuracy. The GDN CEOS is further applied to the prediction of bubble pressure and vapor mole fraction of several binary mixtures using the van der Waals one fluid mixing rules. The accuracy of GDN CEOS is demonstrated by comparing results with three well-known equations of state: Haghtalab-Kamali-Mazloumi-Mahmoodi (HKM1), Modified Peng Robinson (MPR) and Patel-Teja (PT) cubic equations of state.

中文翻译：

---

纯化合物和混合物的四参数三次状态方程

摘要 提出了一个四参数三次状态方程GDN-CEOS来描述纯流体和混合物的热力学性质。我们已经根据其余参数投射了四个参数中的三个，并且所有参数都与温度无关。在 CEOS 的有吸引力的术语中提出了一个新的 alpha 函数；这需要从两个降低温度点 T r = 0.5 和 0.7 下的饱和蒸气压数据确定的两个化合物特定参数。因此，GDN CEOS 每种物质有五个输入：临界温度 (Tc)、临界压力 (Pc)、临界压缩系数 (Zc) 和 alpha 函数的两个复合特定参数 (m, n)。成功预测了代表多种官能团的 334 种纯化合物的饱和蒸气压和液体密度。其他热力学特性，如等压和等容热容、声速、压缩液体密度和汽化焓，已使用 GDN CEOS 以非常好的精度计算。GDN CEOS 进一步应用于使用范德华一流体混合规则预测几种二元混合物的气泡压力和蒸汽摩尔分数。通过将结果与三个众所周知的状态方程进行比较，证明了 GDN CEOS 的准确性：Haghtalab-Kamali-Mazloumi-Mahmoodi (HKM1)、修正的 Peng Robinson (MPR) 和 Patel-Teja (PT) 三次状态方程。GDN CEOS 进一步应用于使用范德华一流体混合规则预测几种二元混合物的气泡压力和蒸汽摩尔分数。通过将结果与三个众所周知的状态方程进行比较，证明了 GDN CEOS 的准确性：Haghtalab-Kamali-Mazloumi-Mahmoodi (HKM1)、修正的 Peng Robinson (MPR) 和 Patel-Teja (PT) 三次状态方程。GDN CEOS 进一步应用于使用范德华一流体混合规则预测几种二元混合物的气泡压力和蒸汽摩尔分数。通过将结果与三个众所周知的状态方程进行比较，证明了 GDN CEOS 的准确性：Haghtalab-Kamali-Mazloumi-Mahmoodi (HKM1)、修正的 Peng Robinson (MPR) 和 Patel-Teja (PT) 三次状态方程。