Effect of Air Velocity and Temperature on Energy and Effective Moisture Diffusivity for Russian Olive (Elaeagnusan gastifolial L.) in Thin-Layer Drying

Document Type : Research Note


Department of Agricultural Machinery Engineering, Faculty of Agriculture, Tarbiat Modares University, Tehran, I.R. IRAN


Thin layer drying of Russian olive (Elaeagnusan gastifolial L.) fruit using a hot air dryer in order to calculate effective moisture diffusivity, activation energy and energy consumption has been evaluated in this article. The selected variables included three levels of air velocity of 0.5, 1 and 1.5 m/s and three air temperature levels of 50, 60 and 70°C. Increased air temperature increased effective moisture diffusivity but increase in air temperature had an inverse effect. Effective moisture diffusivity (Deff ) calculated for russian olive fruit in different temperatures and air velocities ranged between 5.56×10-11 to 3.18×10-10 (m2/s). The resulting values for activation energy had a minimum of 48.18 kJ/mol for 1.5 m/s air velocity up to a maximum of 63.83 kJ/mol for 0.5 m/s air velocity. The values for total and energy consumption in thin layer drying russian olive ranged between 16.34-75.04 (kW.h).  


Main Subjects

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