paper

  MATHEMATICAL MODELING AND COMPUTER SIMULATION OF A DRUM DRYER

  N. Kasiri, M. Hasanzdeh, M. Moghadam

  Abstract

   In this study, a mathematical model based on principles of heat and mass transfer taking place during the drying process has been developed. Element material and energy balance equations are solved simultaneously using the modified Euler method with time step variation. In order to consider evaporation rate reduction after the critical moisture content, a ζ factor is defined which could be evaluated from drying curve. The developed model is then used as a base to build a simulation program. The program is eventually used to predict the performance of a dryer for baby food compared with real plant measurements. Relatively good compatibility is observed to exist between the predicted and measured data. Errors observed between the calculated results and real plant data are about 10.32% for drying time and 15.40% for final moisture content. The simulator also used to study the behavior of a dryer for qualitative analysis and the influence of different parameters on drying time and product quality.