荔枝红外真空干燥过程火用变特性试验比较  

Experimental Comparison of the Exergy Dynamic During Infrared Vacuum Drying of Litchi

作　　者：徐凤英[1] 陈震[1] 李长友[1] 

机构地区：[1]华南农业大学工程学院,广东广州510642

出　　处：《江西农业大学学报》2014年第2期422-427,共6页Acta Agriculturae Universitatis Jiangxiensis

基　　金：国家自然科学基金项目(31071583)

摘　　要：分析了荔枝红外真空干燥热力系统的过程质量、能量变化,导出了果体及腔内干燥介质的火用变式;结合试验参数测定,对比了不同工艺组合干燥荔枝果体及腔内干燥介质的火用变特性。结果表明,改变荔枝红外真空干燥工艺组合条件,果体及腔内干燥介质的火用变特性不同;两种保压方式,荔枝果体火用均增加,保压时果体火用增幅小,其值随辐射距离、红外线源、加热缓苏比不同而改变,变化趋势与非保压时腔内干燥介质的火用变相近,各保压工艺组合干燥,腔内干燥介质火用呈锯齿形变化;非保压、SZ线源、120 mm辐射距离、30 min/15 min加热缓苏比工艺组合干燥,果体火用及干燥效率高。可为物料红外真空干燥的高效、节能加工提供参考。The mass and energy dynamic of thermal system during the infrared vacuum drying of litch wasanalyzed,and the exergy dynamic equations between fruit and drying medium in chamber were derived .Besides,the exergy dynamic between fruit and drying medium in chamber in different combined drying processeswere compared combined with the determination of experimental parameters .The results showed that the exergydynamic between fruit and drying medium in chamber in different combined drying conditions varied .When usingtwo methods of pressure maintaining and none maintaining ,the fruit exergy values both increased,the increaseamplitude of exergy value of fruit of the former was small ,and its value changed with radiation distance,infrared linear source and the rate of heating time and tempering time ,and the trend was similar to the exergydynamic of drying medium in chamber of the latter.The exergy dynamic of drying medium in chamber of theformer presented a zigzag shape.The optima of fruit exergy and drying efficiency could be acquired by the com -bined drying condition of pressure non -maintaining,SZ linear source,120 mm radiation distance,30 min/15min rate of heating time and tempering time.The results provides a reference for other material infrared vacuumdrying with high efficiency and energy saving .

关 键 词：荔枝 火用变 红外真空干燥 工艺组合 腔内干燥介质 

分 类 号：S375[农业科学—农产品加工]