Investigation of the thermal Performance of an indirect forced Convection solar dryer for tapioca Chips drying

Abstract

Cassava (Tapioca) is an extensive amount of carbohydrates and is typically dried through the open sun drying process in rural areas, which ultimately decreases the quality of the dried products. Solar dryers are generally preferred green structures for dehydrating the products under measured environments by utilizing clean and eco-friendly solar energy. In this work, an indirect forced convection solar dryer is used to dry the tapioca chips with six influencing factors, and its three levels are used to conduct the experiments as per the DOE Taguchi model of L27 Orthogonal Array in case study -1. The main components of the existing solar dryers are solar air heaters with distinctively designed copper plate fins apart from the regular parts like absorber flat plate, and top glass cover, etc. The solar air heater is packed with sensible heat-storing materials like copper scrap or aluminium scrap among the gap 100 mm between the absorber plate and the back plate, to raise the temperature of the absorbing air as well as to maintain the outlet air temperature of the heater for drying purposes. The next main part of the solar air heater is the drying compartment using chimney and perforated trays, in which the product to be dried are spread in a single layer, additionally, the function of the drying chamber is to support the circulation of hot air inside the drying space to make assured the drying process. The flat plate of the solar air collector comprises two rectangular boxes named the inner box and the outer box. The inner box is kept to the inside of the outer box and the gap among the two boxes is packed with insulating material like thermocol or coconut fibre in order to decrease the conduction heat losses to the outside. newline newline newline