بررسی سینتیک خشک شدن و ضریب انتشار رطوبت مؤثر خرما رقم مضافتی در خشک‌کن خورشیدی کابینتی

In this research drying kinetics, moisture diffusivity and determination of most appropriate mathematical modeling and activation energy of Mazafati dates species were studied under a cabinet solar dryer.Drying experiments were carried out at three air temperatures of 50, 65, and 80ºC and three air velocities of 1.0, 1.5, and 2.0 m/s. Effect of temperature and air velocity evaluated on drying time and shrinkage by using a completely randomized statistical design. Results showed that the effects of temperature and air velocity are significant on drying time. The average increase of temperature from 50ºC to 80ºC caused the drying time to decrease by 70.77%. For determination of most appropriate model, the highest value of R² and the lowest values of c² and RMSE were used. For mathematical modeling, eight empirical models were fitted on experimental data and the best model was selected. The result of regression analysis showed that Page model has the best fitting with data. Moreover, the lowest and highest value of moisture diffusivity were obtained as 4.309×10^-10 and 0.0188×10^-9 m²/s at temperatures of 80^°C and 50^°C, respectively. Also the values of activation energy in the drying of Mazafati dates species were found between 31.22 to 42.27 kJ/mol.