Solar Drying for Food Preservation

flat plate collector are in rectangular panels, from about 1.7 to 2.9 sq. m, in area, and are relatively simple to construct and erest. Air or gas heating collector are employed as solar air heaters. Where an air stream is heated by the back side of the collector plate. Fins attached to the plate increase contact surface. The back side of collector is heavily insulated with mineral wool or some other material. The most favourable orientation, of a collector, for heating only is facing due south at an inclination angle to horizontal equal to the latitude +15 degree. Air has been used so far to a lesser extent as the heat transfer medium in solar collector, but it may have some advantages over water. To decrease the power required to pump the necessary volume of air through tubes, wider flow channels are used. Solar air heater has an important placed among solar heat collector. It can be used as subsystem used in many systems meant for the utilization of solar energy. Possible applications of solar air heaters are drying or curing of agriculture products, space heating for comfort, regeneration of dehumidifying agents, seasoning of timber, curing of industrial products such as plastics.