Control of Forced Convection Drying in Food Slabs

Reaching a desired quality of the dried product and reducing the convection drying energy costs of food are often related to practical or empirical evaluations, relaying on particular operator expertise and equipment conditions. First, the paper presents a forced convective drying simulator. The generalized conjugate multiphase transport model uses an exponential approach for the drying kinetics. The transient flow, temperature, pressure, liquid water and vapours fields are revealed by the simulator for a 2D geometry, in both air and porous solid domains. The simulation results are validated against experimental data, for the case study of convective drying of carrot slabs. Second, based on the simulator space and time predictions of water, temperature and velocity, in air and solid domains, a set of investigations are performed for improving drying operation by means of process control. The approach is used to minimize the duration of the drying process while reducing the energy costs.