【摘要】 本文是在作者1981年提出的Van der Waals型状态方程的基础上的进一步改进。新方程的四个参数可以由临界温度、压力和反映物质特性的新参数-内压因子α计算,由此得到的方程的理论临界压缩因子ξ_c是一个和物质特性有关的变值.温度函数α(T)沿用Soave提出的表达式,根据饱和压力线上气液两相的逸度相等的原则确定,并将系数k和η进行了关联。对31种纯物质的饱和气液相体积和气、液相逸度偏差的检验结果表明,改进后的状态方程不仅具有Soave和Peng-Robinson方程原有的优点,而且可以推广到象正二十烷这样的大分子物质:与同类型的Schmidt-Wenzel和Patel-Teja方程比较也具有相当或略好的体积计算精度,气、液相逸度的计算则有明显的改进。更多还原

【Abstract】 A Van der Waals type equation of state for pure fluids is presented in this work. This new equation requires the critical temperature and pressure as well as the new characteristic parameter of substance--the internal pressure factor η, and yields a substance--dependent critical compressibility factor ξ_c. For α(T), the same expression as that used by Soave is chosen, and the coefficient k is treated as a function of η. Test on volumes and on the deviation of fugacities of saturated liquid and vapour for 31 pure substances(up to n-eicosane) indicates that the representation of volumes and the calculation of fugacities of saturated liquid and vapour are improved, in comparison with results of Soave’s, Peng-Robinson’s, Schmidt-Wenzel’s and Patel-Teja’s equation of state.更多还原