Simulation of heat and mass transfer in fractal porous media during freeze drying of biological materials

被引：0
作者：
Peng, Runling [1 ,2 ]
Liu, Changyong [1 ]
Xu, Chenghai [3 ]
Li, Chenghua [1 ]
Li, Quanshun [3 ]
机构：
[1] College of Mechanical Engineering, Shenyang Ligong University
[2] College of Engineering, Shenyang Agricultural University
[3] School of Mechanical Engineering and Automatization, Northeastern University
来源：
Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering | 2009年 / 25卷 / 09期
关键词：
Drying; Fractal porous medium; Freezing; Heat transfer/mass transfer; Spirulina platensis;
D O I：
10.3969/j.issn.1002-6819.2009.09.056
中图分类号：
学科分类号：
摘要：
A mathematical model of freeze-drying process was developed for the biological materials. The model described here took into account the fractal feature of the dried layer. The continuity equations for the water vapor and the inert gas in the dried layer used the diffusivity equation of the fractal porous medium, and the Knudsen diffusivity decreased exponentially with the dried layer thickness. The model was capable of predicting the influence of the fractal feature of the dried layer on the motion of the sublimation interface and the drying time of the freeze-drying process of biological materials. The model could also predict the temperature profile and the concentration of bound water profile in biological materials during the freeze-drying process. The freeze-drying process of spirulina in glass vial was simulated using fractal model by software Matlab and Fluent. The simulation results agree with the experimental data.
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收藏
页码：318 / 322
页数：4
相关论文
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