Modelling coating quality in fluidised bed coating: Spray sub-model

Fluidised beds are widely used in industrial applications for the coating of particles. Little research has been performed in developing a model that is able to predict the quality of the coating process in terms of the coating thickness and uniformity and the occurrence of unwanted side-effects, including agglomeration, attrition and spray loss. The quality of the coating process in a fluidised bed is largely determined by the spray characteristics and the particle motion. As a first step in the development of a new model for the coating process in a top-spray fluidised bed, an accurate spray sub-model that describes the movement and the heat and mass transfers of the droplets in the coating process was created and experimentally validated.

► As a first step in the development of a new quality model for coating process in top-spray fluidised bed, a new spray model is presented. ► The model considers individual droplets and makes use of a scale factor that reduces computational power. ► For droplet temperatures between 20 °C and 80 °C in saturated air, it could be concluded that the model gave a good prediction of the droplet spatial temperature evolution.