【摘要】 精馏塔的动态模型常常涉及到许多变数,这就严重地限制了它的应用,作者采用三阶自然样条函数作为基本函数整体模拟以及分别按精馏段和提馏段模拟浓度变化曲线以达到减少变数的目的。采用加权残差法处理非线性微分方程式组,最后用数值方法求解。作者将这两个动态模型分别用于二元系及三元系的具有48层及39层实际板的精馏塔,使回流比分别变化±5%、±10%,再沸器热负荷分别变化±2.5%,±5%,进料流率变化±5%,关键组份在进料中的组成变化10%,解出当精馏塔最终达到稳态时的组成及其他有关参数,在达到令人满意的精确度的情况下计算机时间可节省60%以上。更多还原

【Abstract】 Dynamic models for distillation columns generally involve a large number of dependent varibles, which severely limits thier usefulness. The author,in cooperation with Prof. E.H. Wissler in University of Texas at Austin,employed natural spline functions of degree three as basic functions to simulate the composition profiles in the distillation column fully for whole one and separately for the rectifying and stripping section. In order to reduce the number of variables the method of weighted residuals was used to treat obtained set of non-linear differential equations. The results were obtained by means of numerical method. These two models were applied to the binary and ternary distillation columns with 48 and 39 trays, respectively. By changing reflux ratio by ±5%,±10%, he duty of reboiler by ±2.5%,±5%, the flowrate of feed by±5% and the composition of the key components in feed by 10%, the compositions and other variables at each tray were obtained when the column reached steady-state. It was shown from computational results that the computer time was saved by more than 60% with satisfied accuracy.更多还原