Performance evaluation of PV ventilated hybrid greenhouse dryer under no load condition

Abstract

The PV ventilated hybrid greenhouse dryer was designed and fabricated for drying of food grains. The greenhouse dryer with 446.7 X 213.4 cm size and with central height of 259 cm was constructed using 50.8X25.4 mm MS pipe, 19X30.2 mm MS angles. Clear twin wall polycarbonate sheet with 6 mm thick was used insulate the greenhouse dryer structure. Performance evaluation was conducted under no load test condition. It was observed that, the average temperature inside the dryer was 7.6-13.4⁰C and 6.3-13.2⁰C (22-43%) higher and average relative humidity was 26-47% and 23-40% lower than ambient temperature and relative humidity during May and December months respectively. Exhaust air flow rate varied in the range of 38.93-81.95 m³/min and 28-63 m³/min during May and December respectively. Elevated greenhouse dryer air temperature and reduced relative humidity would reduce the drying time considerably.