| Summary: | The present study examined the drying kinetics of carrots and the effectiveness of passive indirect solar dryer without (setup-I) and with (setup-II) thermal energy storage (TES). A module containing paraffin wax as a TES unit was incorporated after the test was completed in setup-I to create setup-II. The sample slices were dried in setup-I and setup-II at a drying rate of 0.5 and 0.59 kg/h, respectively. In setup-I, the sample dried from 9.13 to 0.478 dry basis (db) in 16 h, whereas, setup-II took 15 h. The thermal efficiency of the solar heater and actual heat supply for the same were 56.84 & 60.79% and 705.64 & 730.45 W, respectively. Similarly, the average heat and mass transfer coefficients (h and hm) were 6.32 & 7.08 W/m2 K and 0.0055 & 0.0062 m/s, and average effective diffusivity (De) for the same setups were 6.7 × 10−9 and 7.24 × 10−9 m2/s, respectively. Furthermore, the specific energy consumption and specific moisture extraction rate for the same were 3.5 & 0.28 kWh/kg and 0.29 & 3.62 kg/kWh, respectively. Setups I and II had an average drying efficiency of 7.5 and 10.25%, respectively. The activation energy was evaluated for both setups. The De, h and hm were correlated with moisture content for both setups. In addition to helping the drying process to be completed in a day, setup-II performed better in all the evaluated parameters than setup-I. To ensure the reliability of the results, an experimental uncertainty analysis was conducted.
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