MATHEMATICAL MODELING FOR DRYING FIGS IN THIN-LAYER USING MECHANICAL DRYER

Helmy, M. A.; Sorour, H. M.; El-Kholy, M. M.; El-Mesery, H. S.

doi:10.21608/mjae.2010.105356

MATHEMATICAL MODELING FOR DRYING FIGS IN THIN-LAYER USING MECHANICAL DRYER

Document Type : Original Article

Authors

¹ Professor of Agric.Eng., Agric. Eng. Dept., Fac. of Agric., Kaferelsheikh Univ., Egypt.

² Senior Researcher, Agric. Eng. Res. Institute, Agric.Res. Center, Dokki, Giza, Egypt.

³ Agric. Eng., Agric. Eng. Res. Institute, Agric. Res. Center, Dokki, Giza, Egypt.

10.21608/mjae.2010.105356

Abstract

In the present work, selected mathematical thin-layer drying models were fitted to experimental data using non-linear regression analysis techniques. The drying behavior was examined and simulated using four different thin layer drying models (simple, modified simple, logarithmic and two-term exponential model). An empirical equations relating the studied drying parameters with the drying constants of each model were also developed. The analysis was conducted based on the final moisture content (Mf) and the equilibrium moisture content (Me) for calculating the moisture ratio (MR). The results indicated that, both forms of different drying models equations described the drying behavior of whole figs satisfactorily as indicated by the high values of coefficient of determination (R2) and low values of standard error (SE).
The studied drying models were also examined and compared for simulating the drying data obtained from the actual drying of whole figs to select the most applicable model for predicting whole figs moisture content during the drying process using the mechanical dryer
The experimental data used to fit the thin-layer drying of whole figs (Ficus carica). The effect of drying air temperature and velocity on the coefficients of the best suited moisture ratio (MR) model were determined by multiple regression method. In the experimental, the air was passed through the chamber at a variety of air velocity (0.2, 0.4, 0.6 and 1 m/s), temperature (55, 65, 75 and 85 oC) and different of pretreatment of whole figs.
According to the results, the reduction rate of figs moisture content was increased with the increasing of drying air temperature and air velocity in all pretreatment of whole figs.

The logarithmic model equation could be considered the most proper model for describing the drying behavior of whole figs and predicting the change in moisture content. The value of (Me) for all drying models, substituting in calculating the moisture ratio showed better prediction of moisture content in comparison with value of (Mf) for all pretreatment of whole figs.

Main Subjects

Processing Engineering of Agricultural Products

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