Modelling and Simulation of Momentum, Heat, and Mass Transfer in a Deep-Bed Grain Dryer

Abstract

This article concerns the modelling and simulation of a deep-bed grain dryer in a large diameter-column. Two-dimensional (2D) models of deep-bed grain dryers were built by considering simultaneously momentum, heat, and mass transfer in the drying phase together with coupled heat and mass balance in the grain phase. The dynamic equations are solved numerically by using finite difference method. The momentum equations are applied to simulate pressure drop and velocity field of the drying air across the bed. The mass and heat balance in the two phases determine the profile of temperature and moisture content in both phases. Further, drying rate curves for various temperature of inlet drying gas together with moisture content of grain were simulated. The simulated profiles are in close agreement with experimental data.

Keywords:

• Deep bed drying
• Coupled momentum mass heat transfer
• Navier-Stokes equation

Acknowledgments

Part of financial support from Indonesian Research Council is acknowledged. Part of routine to solve momentum equations was originally developed by Dr. Yazid Bindar at the Department of Chemical Engineering ITB and is gratefully acknowledged.