In order to investigate the transfer characteristics of the water-oat drying process, a laboratory convective hot air dryer was applied to study the influences of drying temperature and thickness of water-oat slice on the drying process. The experimental data of moisture ratio of water-oat slices were used to fit the mathematical models, and the diffusion coefficients under different drying temperatures were calculated, the relative relations between the diffusion coefficient and drying temperature were also related. The results show that the drying temperature influences the drying process significantly, and the thinner slice benefits the moisture diffusion. Among several familiar numerical moisture ratio models, Page model of moisture ratio was found to be the most satisfactory one for the description of the kinetics of the hot air drying water-oat slices process. It was also found that, when the thickness of water-oat slice is 0.003 m, with the increase of temperature from 55℃ to 75℃, the water diffusion coefficient varies from 3.440×10-9 m2·s-1 to 6.357×10-9 m2·s-1; and it fits the Arrhenius equation, the activation energy is 27.86 kJ·mol-1. Under the same temperature, the experiments show that the thickness of the drying material has almost no influence on the water diffusion coefficient%为了探讨茭白干燥的传递特性,在对流热风干燥实验装置中进行了茭白片薄层干燥实验,研究了干燥温度、片的厚度对干燥过程的影响,将试验的水分比与数学模型进行了拟合,计算了不同温度下的水分扩散系数,并关联了其与干燥温度的关系.结果表明:干燥温度对干燥过程影响显著,薄片有利于水分扩散:用Page模型来描述茭白片热风干燥动力学令人满意;茭白片厚度为0.003m时,随风温升高,水分扩散系数从3.440×10-9 m2·s-1增大到6.357×10-9m2·s-1,并符合阿累尼乌斯方程,活化能为27.86 kj·mol-1.相同温度下,物料中水分的扩散系数基本不受厚度影响.
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