Thin layer drying kinetics of Gundelia tournefortii英文电子书.pdf

food and bioproducts processing 9 0 ( 2 0 1 2 ) 323–332 Contents lists available at ScienceDirect Food and Bioproducts Processing j o u r n a l h o me p ag e: w w w. elsev /locate/fbp Thin layer drying kinetics of Gundelia tournefortii L. Duygu Evin ∗ Firat University, Department of Mechanical Engineering, Elazig, Turkey a b s t r a c t The literature surveyed revealed that the drying kinetics of Gundelia tournefortii has not been investigated. In this study, mathematical modeling of the thin layer drying kinetics of G. tournefortii is investigated for both the microwave and open sun drying conditions. Five different microwave power levels ranging from 90 to 800 W were used for the microwave drying. Solar radiation for the open sun drying varied from 350 to 1100 W/m2 . Drying took place in the falling rate period. Increasing the microwave power caused a significant decrease in drying time. The experimental moisture loss data were fitted to the 14 thin layer drying models. Among the models proposed, the Midilli model precisely represented the microwave drying behavior of G. tournefortii with the coefficient of determination higher than 2 0.996 and mean square of deviation ( ), root mean square error (RMSE) and mean bias error (MBE) lower than 1.82 × 10−4 , 12 × 10−3 and 1.4 × 10−4 , respectively for all the microwave drying conditions studied. Values of drying constant (k) were in the range of 0.0098–0.2943 min−1 and the effective moisture diffusivities (Deff) of G. tournefortii ranged from 5.5 × 10−8