Analytical two-dimensional analysis of the transport phenomena occurring during convective drying: Apple slices Original Research Article

The two-dimensional analysis of transport phenomena occurring during drying of a rectangular object is performed employing analytical method. The external flow is predicted numerically and then the convective heat transfer coefficient is determined during convective drying. The convective mass transfer coefficient is obtained through the analogy between the thermal and concentration boundary layers. After calculating average heat and mass transfer coefficients, the heat and mass transfer equations within the object are analytically solved and temperature and moisture distribution is obtained. The present study is contemplated to fill a gap in analytical modeling of two-dimensional heat and mass transfer equations; since most of analytical solutions are one-dimensional, they cannot show the effect of front and rear faces of the moist object on the drying, so the motivation to do this study is to show mentioned effect. Results demonstrated that front and rear faces have significant influences on the drying which should be considered in modeling. It is expected that the model can be applied for other food products and processes involving similar phenomenon. The analytical results are compared to the numerical ones, presenting a reasonable adjustment.