摘要
依据液－ 固扩散过程的机理建立浸取过程的数学模型。利用实验数据应用参数估值方法对该模型中的参数进行估值，并介绍了一种计算扩散系数的有效方法，通过实验证明：把等温过程得到的数据与根据模型预测的数据相比较，可 以发现干菌 体的浸取过 程可以被描 述为适用于 费克定律的 扩散过程；数模的精度取决于消除外扩散影响程度的大小；同时还得出在 不同温度下求得扩散系数 与温度的关系。文献报道的溶质在固体中的扩散系数一般为１０ － ９ ～１０ － １４ ｍ ２／ｓ ，经本实验求出的扩散系数值在此范围内。采用本方法得到的扩散系数 与温度符合 阿仑尼乌斯 方程，该模型 与传统方法 比较具有实 验参数少、规律性好及计算简单等优点。验证结果表明：采用建立模型计 算所得扩散系数与实验结 果的平均相对误差为±４ ．３ ％
A mathematical model of extraction process is presented on the mechanism of diffusion in liquid-soild extraction process. Parameter estimation in the model is made by using the method of parameter estimation and experimental data. A new method to predict diffusion coefficient is introduced. The data obtained in constant temperature process are compared to the data calculated by the model. It has been found that the extraction process of dry thalli fits to the process expressed by Fick′s First Law. Precision of model depends on the extent of the effect of the external diffusion. The relationship between the diffusion coefficient and experimental temperature is obtained. The diffusion coefficients in the range of 10 -9 ～10 -14 m 2/s have been reported in many papers. And the coefficients obtained by using this method fall in this range too. The relationship between diffusion coefficients and temperature fits to exponent equation. The model is of the advantage of less parameters and simpler calculation. The mean relative error of the calculating values of the diffusion coefficient is ±4.3%.
出处
《抚顺石油学院学报》
1999年第3期11-13,共3页
Journal of Fushun Petroleum Institute
关键词
扩散系数
参数估值
数学模拟
计算
灰黄霉素
Diffusion coefficient
Parameter estimation
Mathematical simulation
