A Numerical Approach to Determine Some Properties of Cylindrical Pieces of Bananas During Drying

作者：da Silva Wilton Pereira^*; e Silva Cleide M D P S; da Silva Junior Aluizio Freire; de Melo Queiroz Alexandre Jose

来源：International Journal of Food Engineering, 2015, 11(3): 335-347.

DOI：10.1515/ijfe-2014-0199

• diffusion models
• mass diffusivity
• convective transfer coefficient
• cylindrical geometry
• moisture distribution

This article uses several liquid diffusion models to describe convective drying of bananas cut into cylindrical pieces. A two-dimensional numerical solution of the diffusion equation with boundary condition of the third kind, obtained through the finite volume method, was used to describe the process. The cylindrical pieces were cut into the following dimensions: length of about 21 mm and average radius of 15 mm. Drying air temperatures were 40 degrees C, 50 degrees C, 60 degrees C and 70 degrees C. In order to determine the process parameters, an optimizer was coupled with the numerical solution. A model that considers the shrinkage and variable effective moisture diffusivity well describes drying for all the experimental conditions, and enables to predict the moisture distributions at any given time. For this model, the determination coefficient has varied from 0.99937 (70 degrees C) to 0.99995 (40 degrees C), while the chi-square ranged from 3.41 x 10(-4) (40 degrees C) to 4.15 x 10(-3) (70 degrees C).

• 出版日期2015-6