Modeling and simulating the drying of grass seeds (Brachiaria brizantha) in fluidized beds: evaluation of heat transfer coefficients

• Main Authors: A. C. Rizzi Jr., M. L. Passos, J. T. Freire
• Format: Article
• Language: English
• Published: Brazilian Society of Chemical Engineering 2009-09-01
• Series: Brazilian Journal of Chemical Engineering
• Subjects: Fluidized bed; Heat transfer; Fluid dynamics; Grass seeds
• Online Access: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0104-66322009000300010

This work is aimed at modeling the heat transfer mechanism in a fluidized bed of grass seeds (Brachiaria brizantha) for supporting further works on simulating the drying of these seeds in such a bed. The three-phase heat transfer model, developed by Vitor et al. (2004), is the one used for this proposal. This model is modified to uncouple one of the four adjusted model parameters from the gas temperature. Using the first set of experiments, carried out in a laboratory scale batch fluidized bed, the four adjusted model parameters are determined, generating the heat transfer coefficient between particles and gas phase, as well as the heat transfer coefficient between the column wall and ambient air. The second set of experiments, performed in the same unit at different conditions, validates the modified model.