作　　者： ; ;

机构地区： 东北农业大学工程学院

出　　处： 《农业工程学报》 2005年第1期159-162,共4页

摘　　要： 该文在薄层干燥试验台上研究了苜蓿的干燥特性。试验结果为:干燥温度越高,苜蓿的干燥速度越快。试验确定了临界干燥速度与干燥温度间的方程,定量分析了苜蓿干燥速度与干燥温度间的关系。运用量纲分析方法,得到干燥动力学常数K与初始含水率Mo,样品质量G,干燥温度T,介质流速v,茎秆长度l的经验公式,可以准确分析和评价苜蓿在各种条件下的干燥特性。 Both alfalfa drying property and constant K involving drying parameters of the alfalfa were studied. Due to the difference in physical structure and chemical characteristics of fresh alfalfa component, the leaf, fine stem and coarse stem show different drying rates under the same drying condition. The higher the heated air temperature is, the higher the drying speeds of the drying speeds of the stems and leaf are. As drying temperature is over 120°C, the drying rate was found to increase significantly with initial alfalfa moisture content. This may be attributed to thermal damage to waxy surface, which helps moisture retention in the plant, thereby increasing drying rate up to a critical level. The changes of the stem, the leaf and the whole stalk drying rates with the heated air temperature were obtained. In order to reduce the moisture difference between the stems and leaf of the post-drying alfalfa, it is necessary to crush the stems through mechanical treatment. The dimensional analysis method was used to establish an empirical equation involving the drying kinetic constant K and the initial moisture content, heated air velocity and temperature etc. The equation is useful to feasibly determine the drying parameters, which may better preserve the shape, color and flavor of the post-drying alfalfa, and reduce its nutritional component loss such as protein, vitamin etc.

关 键 词： 苜蓿 干燥 量纲分析法

领　　域： [农业科学] [农业科学]