芒果微波干燥特性及数学模型研究

Mango Microwave Drying Characteristics and Kinetic Model Analysis

为研究芒果微波干燥特性,并确定其最适干燥动力学模型。以芒果为原料,探讨不同微波功率(1250 W和2500 W)和切片厚度(8、10、12 mm)对芒果干基含水率和干燥速率的影响;其次,采用6种常见的数学模型对微波干燥进行非线性拟合,得到芒果微波干燥动力学模型。结果表明,芒果微波干燥过程主要表现为升速阶段和降速阶段。微波功率越大,干燥速率越快,干燥耗时越短;切片厚度越大,干燥速率越慢,干基含水率到达平衡所需时间越长。芒果微波干燥过程中的水分有效扩散系数随微波功率增加而增大。通过模型拟合发现,Wang and Singh模型是芒果微波干燥的最佳模型,具有最大决定系数R2(0.9957)、最低卡方χ2(0.0005)和最小残差平方和RSS(0.0079),可有效描述芒果微波干燥过程。

In order to study the microwave drying characteristics of mango and to determine its optimal drying kinetic model.The effects of different microwave power(1250 W and 2500 W)and slice thickness(8,10 mm and 12 mm)on the moisture content and drying rate of mango were explored with mango as a raw material;secondly,six common mathematical models were used for non-linear fitting of microwave drying to obtain the mango microwave drying kinetic model.The results showed that the microwave drying process of mango was mainly manifested in the ascending and descending stages.The higher the microwave power,the faster the drying rate and the shorter the drying time;the greater the slice thickness,the slower the drying rate,and the longer the time required for the moisture content of the dry base to reach equilibrium.The effective diffusion coefficient of moisture in the microwave drying process of mango increased with the increase of microwave power.Through model fitting,it was found that the Wang and Singh model was the best model for mango microwave drying with the maximum coefficient of determination R2(0.9957),the minimum chi-squareχ2(0.0005),and the minimum residual sum of squares RSS(0.0079),which can effectively describe the mango microwave drying process.