Experimental investigation of drying kinetics of green chilli and okra using indirect solar dryer with evaluation of dryer performance

In this study, green chillies and okra were dried using an indirect type solar dryer ITSD dryer and their drying kinetics were evaluated. The initial moisture content (MC) of green chilli was 8.3984 kg/kg of dry basis (db) and it was reduced to final MC of 0.2218 kg/kg of db. Also, MC of okra reduced from 10.1234 to 0.3348 kg/kg of db. The efficiency of solar air collector and the drying efficiency were estimated during the drying of green chilli and okra. The activation energy was found to be 32.484 and 25.330 kJ/mol and effective moisture diffusion coefficient was found to be 1.464 × 10−9 and 5.1798 × 10−9 m2/s for green chilli and okra, respectively. The surface transfer coefficients (both heat and mass) of green chilli and okra were estimated. Uncertainty analysis was performed on all the measured and derived drying parameters.