MATHEMATICAL MODELING OF TEMPERATURE AND HEAT PROFILES IN PILOT REFRACTANCE WINDOW DRYING SYSTEM

Document Type : Original Article

Author

Lec., Agric. Eng. Dept., Fac. of Agric., Cairo Univ., Egypt.

Abstract

The design of the Refractance Window (RW) drying system was based on a novel concept in which hot water is circulating beneath and in contact with a transparent plastic conveyor belt where a thin filmof puree is to be dried. A mathematical model that accounts for heat and mass transfer, and temperature buildup was developed for the RW pilot dryer. One set of equations was developed to predict temperatures of the Mylar plastic sheet and the product during the drying process. Another set of equations was developed to predict the heat requirements for drying of mango puree using the same system. This model was validated using the experimental results obtained at MCD Technologies, Inc., Tacoma, WA, USA. Good agreement was found among the temperatures obtained from experimental results and from the model. This model can be used to predict temperatures and heat profiles for the RW dryer for drying mango puree as well as other fruits and vegetables purees. 

Main Subjects

References

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