明胶凝胶水分扩散系数的数值法估计

Estimating Water Diffusivity in Gelatin Gel by Numerical Method

利用水分含量不同的两段明胶凝胶柱并成的渗透扩散实验模型、Fick第二扩散模型、明胶凝胶水分含量与其密度关系,采用动态步长手段,对20℃时水分质量浓度在811～933kg/m3范围的明胶凝胶水分扩散系数进行了数值法估计.结果表明,无论将水分扩散系数作为常数还是作为水分含量的函数处理,在实验水分含量范围内,得到的水分扩散系数的估计值均接近3×10-12m2/s.这一估算结果得到了验证性实验的较好支持.

The water diffusivities in gelatin gel with moisture content between 81.1～93.3 kg/m3 at 20 ℃ were numerically estimated by a dynamical steps technique based on penetrating diffusing experimental set of gelatin gel pillar, Ficks second law of diffusion, a relation between the moisture content and the density of gelatin gel. The results showed that the water diffusivity of gelatin gel was close to a constant of 3×10-12(m2/s) when it was treated either as a constant or as a function of moistwre content. The estimated results was verified by experiment.