Keywords: copra drying, heat storage materials, solar dryers, specific moisture extraction rate, SMER, indirect forced convection, solar energy, solar power, sand, aluminium scrap, solar air heaters
Performance of a solar drier with and without heat storage material for copra drying
An indirect forced convection solar drier integrated with heat storage material was developed to test its performance for copra drying. The drier consists of a solar flat plate air heater integrated with a sensible heat storage unit, a drying chamber and a centrifugal blower. The experiments were carried out with and without the integration of heat storage materials. Sand mixed with aluminium scrap was used as a heat storage material in solar air heater. The moisture content (wet basis) of copra was reduced from about 52% to about 8% in 80 and 104 hour, respectively, for solar drier integrated with and without heat storage materials. The Specific Moisture Extraction Rate was estimated to be about 0.81 and 0.94 kg kW hour−1 for the solar air heater with and without heat storage materials, respectively. The average solar drier thermal efficiency was estimated to be about 23% in both the drying modes.