基于Fick第二扩散定律和Fourier定律,用以描述球状合湿生物多孔材料内部的传热传质数学模型;运用有限差分法进行数值模拟计算,得到物料在不同工况下的内部温湿度分布曲线,并以胡萝卜为实验材料,对模拟值和实验值进行比较.结果表明:在整个干燥过程中数值模拟结果和实验数据吻合较好,该模型可以用来预测胡萝卜干燥过程中内部的温湿度分布;模拟结果表明:胡萝卜在干燥过程中各层水分蒸发速率不同,位于表层的水分先蒸发,由表层到中心干燥速率依层降低,湿度呈现表低内高的分布规律.
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