Hamed Darabi; Ali Asghar Zomorodian
Abstract
Lemon is one of the most important citrus fruit and is consumed as fresh and dry. In this study the effect of
fruit moisture content on the size, sphericity, geometric mean diameters and kernel density were studied. The
bulk density and porosity were also evaluated in three different arrangements. ...
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Lemon is one of the most important citrus fruit and is consumed as fresh and dry. In this study the effect of
fruit moisture content on the size, sphericity, geometric mean diameters and kernel density were studied. The
bulk density and porosity were also evaluated in three different arrangements. Airflow resistance is a
fundamental parameter for designing an efficient drying and aeration systems for lemon fruit bed. Using a
laboratory test rig, two sets of experiments were carried out: thick and thin layers. In the thick layer experiments
4 bed depths, 11 air flow rates and 4 air temperatures were adopted as independent variables. In the thin layer the
effect of filling arrangements in three patterns: A, B and random, at 5 moisture contents and 11 flow rates on
pressure drop were envisaged. Results showed that all the physical parameters listed decreased by reducing
moisture content. Results indicated that resistance to airflow through a column of lemon fruit increased with
increasing bed depth and airflow rate. In the latter experiment pressure drop decreased with a decrease in
moisture content. Airflow rate was the most significant factor affecting the pressure drop of lemon fruit in the
both experiment. Also the filling arrangement B has a higher affect on pressure drop comparing with other
arrangements. Three applicable models (Shedd, Hukill & Ives, and Ergun) were used to evaluate the pressure
drop data. The Ergun model, with higher values for coefficient of determination and lower values for root mean
square error, is the best model for predicting pressure drop across lemon fruit bed for the conditions studied.
