SOLAR CABINET DRYING OF GREEN CHILIES AND POTATO CHIPS - AN EXPERIMENTAL STUDY

摘要

An indirect forced convection solar dryer is designed and fabricated to investigate its performance under the hot and dry climatic condition of Jaipur, India. The system consists of flat plate heater and drying chamber with two shelves and a chimney. Dimensions of heater and drying chamber are 1.21 m × 0.87 m and 0.5 × 0.5 × 0.5 m respectively. Air heater is inclined at 42° with horizontal and oriented in the South-North direction. During experimentation 15 temperatures, relative humidity, air velocity and solar intensity were measured hourly in the month of May, 2010 for drying of green chilies and potato chips. Solar intensity varied between 490-822 W/m~2 and maximum air temperature rise was 22℃. Hot air at 56-60°C from the collector is supplied through 3.5 cm diameter PVC pipe at the bottom of the drying cabinet. The moisture content and weight of chilies was reduced from 85% to 15% and 2 kg to 0.414 kg in three days respectively. Moisture content of potato chips was reduced from 84% to 11% and weight from 2 kg to 0.342 kg in one day. Results of the present study show that the drying time is reduced and quality of the final products is superior.