Ventilation drying of a packed wheat bed: Modified heat and mass transfer models considering shrinkage during drying

摘要

During drying of a packed wheat bed, decrease in the bed height caused by moisture reduction is significant. However, this phenomena has not been formulated mathematically before. In this paper, a new mathematical model of heat and mass transferequations including bed shrinkage due to moisture reduction during drying was developed. In this regard, experiments were conducted on moisture content, temperature, bed height and static pressure in a packed wheal bed. Calculated and measured valuesfitted closely after introduction of bed shrinkage during drying. Thus the new model which considered shrinkage in the packed wheat bed during drying was found to be suitable to predict the moisture content, temperature and bed height.