In the present work, the effective moisture diffusivity and activation energy were calculated using an infinite series solution of Fick’s diffusion equation. The results showed that increasing drying temperature accelerated the drying process. All drying experiments had only falling rate period. The average effective moisture diffusivity values varied from 2.807x10 to 6.977x10m s over the tempe...

thin layer drying behavior of sweet lemon slice was experimentally investigated in a convective type dryer and the mathematical modeling performed, using thin layer drying models given in literature. drying experiments were conducted at inlet drying air temperatures of 40, 50, 60, 70 and 80 ?c; two slice thicknesses of 3 and 6 mm, and, at one drying air velocity of 0.5 m/s with three replicatio...

We analyze the effective diffusivity of a passive scalar in a two-dimensional, steady, incompressible random flow that has mean zero and a stationary stream function. We show that in the limit of small diffusivity or large Peclet number, with convection dominating, there is substantial enhancement of the effective diffusivity. Our analysis is based on some new variational principles for convect...

In this paper we establish conditions for the maximal, Pe, behavior of the effective diffusivity in time-periodic incompressible velocity fields for both the Pe oc and Pe 0 limits. Using ergodic theory, these conditions can be interpreted in terms of the Lagrangian time averages of the velocity. We reinterpret the maximal effective diffusivity conditions in terms of a Poincar6 map of the veloci...