Abstract: By using a cubic spline function to describe the binary excess free enthalpy function Q, a new indirect method for calculating binary vapor composition y from T, p and liquid composition x has been established. Broyden-Newton -Raphson iteration procedure was used for solving the differential equations. Practical calculation examples indicated that this method was reliable and showed good convergence. The calculated results were in good agreement with the experimental data. Moreover, neglect of the excess properties during calculation exerts very little influence on the results.

摘要： 将三次样条函数应用于表达二元系过量自由焓函数Q,由此建立了在汽液平衡中由T、p、x数据推算y的间接算法.非线性方程组的求解采用Brovden改进的Newton-Raphson迭代程序.实例计算表明,本方法结果可靠,收敛速度快,与实验值符合良好.计算还表明,略去过量性质对结果影响不大.