Experimental investigation of a novel indirect solar dryer implementing PCM as energy storage medium

A novel indirect solar dryer (ISD) design using phase change material (PCM) as energy storage medium was experimentally investigated. The system consists of two identical solar air heaters, drying compartment, PCM storage units and a blower. The ISD was tested under no load with and without PCM at a wide range of mass flow rates (0.0664-0.2182 kg/s). It is found that after using the PCM, the temperature of the drying air is higher than ambient temperature by 2.5-7.5 degrees C after sunset for five hours at least. In addition, the mass flow rates of 0.1204 and 0.0894 kg/s give the peak values of the drying temperature when the ISD is operated with and without PCM, respectively. The novel design successfully maintains the desired temperature for seven consecutive hours every day. This helps reaching the final moisture content of Ocimum Basilicum and Thevetia Neriifolia after 12 and 18 h, respectively. (C) 2014 Elsevier Ltd. All rights reserved.