In order to solve the problems in traditional drying technology of preserved fruits, a mini all-weather solar dryer was designed and manufactured based on characteristics and requirements of preserved fruits produced in Guangdong province. The solar dryer is composed of heat-collection plate, drying chamber and blower. It can collect sun radiation to heat air and water, store heat through hot water tank. It also has an assistant heating system in water tank.Forced air convective drying, natural convective drying and greenhouse drying can be reached by the designed dryer.The experiments of drying Ganshimei (intermediate moisture salted plum) were carried out to test the dryer's performance. The working efficiency of heat-collection plate and drying chamber, the material balance and energy consumption of the drying system were calculated. And the parameters of the dryer were determined. The total drying efficiency of the forced air convective drying reached to a high level of 63.40％.Comparing with the traditional open sun drying, the drying rate of the forced air convective drying was 9.99 g/(100 g·h), which was 201.2％ of the open sun drying's. And the drying time of the forced air convective drying was 12 h, much less than 50 h of the open sun drying's.Meanwhile the sugar and acid content loss of the forced air convective drying samples were less than that of the open sun drying samples.%为了解决凉果传统自然日晒干燥中存在的干燥过程耗时长,占地面积大、受天气控制和环境条件影响等问题,根据凉果的特性和干燥要求,设计研制了小型全天候太阳能干燥机.设备由集热器、干燥室和鼓风机等主要部分组成,具有集热、贮能和辅助加热等功能,可实现强制对流干燥、自然对流干燥和温室干燥等干燥模式.以干湿梅作为样品进行了干燥机的干燥性能试验,对干燥机集热器和干燥室的工作效率进行了计算、对干燥过程中的物料及能量进行了衡算,测定计算的设备干燥总效率为63.40%,达到较高水平.对于干湿梅的干制试验结果显示,设备的强制对流干燥模式的干燥速率平均达9.99g/(100g/h-1),较自然日晒干燥的提高了201.2%,干燥时间为12h,较自然日晒干燥的缩短了76%,干制产品的糖、酸损失也较自然日晒干燥的略小.
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