山核桃微波干燥动力学模型研究
Study on the microwave drying characteristics and dynamic model of kernel of hickory( Carya cathayensis Sary)
-
摘要: 针对山核桃坚果热风干燥效率低、能耗大、品质差等问题,采用单因素实验法,研究微波功率和装载量对山核桃坚果微波干燥特性的影响。根据微波干燥过程中山核桃坚果水分变化规律,探讨了不同微波功率、装载量下山核桃坚果干基含水率和失水速率随时间变化的规律,并建立山核桃坚果微波干燥动力学模型。实验结果表明:与装载量相比,微波功率对山核桃坚果干燥速率的影响大;山核桃坚果微波干燥过程分为加速干燥阶段和降速干燥阶段。通过分析,山核桃坚果微波干燥的动力学模型满足Page方程,根据干燥实验数据应用Matlab软件对干燥模型进行回归拟合求解,其模型系数在0.99以上。Abstract: According to the problem of low drying efficiency,high energy and poor quality during hot- air drying process,the effect of microwave power and material load on microwave drying characteristics of kernels were studied by using the single factor experimental method. According to moister dynamics of hickory during microwave drying process,the relationships between the dried basis moisture content,the drying rate and drying time were analyzed under different microwave power and material load.The microwave drying dynamics model was established. The results showed that the drying rates of hickory were markedly affected by microwave power compared with material load. The drying process contained two stages: speeding up and speeding down.Microwave drying of hickory was analyzed to meet the Page equation dynamic model.The experimental drying data of hickory were used to fit the drying model and coefficients of models were above 0.99.