Forced Convection Agricultural Solar Dryer

Abstract

A solar dryer utilizes the freely available solar energy which reduces the drying time as compared to open sun drying. Solar dryers have lower operational costs as compared to conventional electric dryers. This provides an interest in the design and fabrication of solar dryers over conventional dryers. In this experimental work, a forced convection solar dryer has been built with waste plastic bottles for drying the agricultural crop to study the drying of ginger in comparison with open sun drying. The black painted GI sheet was inserted into the plastic bottle which acts like a collector and attached to the greenhouse dryer to dry the crop. The performance of the solar dryer was carried out with and without plastic bubble wrapper film on the cylindrical collector. The temperature, air velocity, and moisture removal rate were measured. Based on the experimental investigation, the drying time of the crop was reduced by insulating the bottles with a waste plastic bubble wrapper. The temperature of the air passing through the dryer was higher in the case of the dryer with insulation. The waste plastic bubble wrapper reduced the heat loss to the surroundings and enhanced the drying rate of the crop.