Design, Fabrication and Performance Analysis of Indirect Solar Dryer

Abstract

This work aims to design, fabricate and analyse the performance of the indirect type of solar dryer. The solar dryer uses Silica Gel chamber, to dehumidify the atmospheric air before it picks up moisture from product to be dried, to increase drying rate. The design of solar dryer utilizes the indirect solar heating principle, which means the heat is transferred to the material to be dried by a fluid medium (air). Solar dryer is totally fabricated from material available locally. Grapes and Chilies are selected as drying material. The time required for reducing the moisture from initial moisture content to final moisture content was recorded for both Chiles and Grapes. Grapes placed in the dryer required only 10 days, to attain final moisture content as compared to the open sun drying which usually takes 20-25 days to reach final moisture content. Also, chilies are dried within three days only to final moisture content. The solar dried samples show superior quality in terms appearance, color quality, taste, nutritional quality, and odor. Also, it is shown that drying period can be reduced by using silica gel. The economic analysis of the solar dryer is also done by simple payback period method.