ABSTRACT
Fluidized bed coating is one of the potential encapsulation methods in which a particulate solid material is entrapped by spraying a coating solution directly into fluidized particles. This chapter presents all mechanisms and critical aspects in the top-spray fluidized bed coating process via the computational fluid dynamics (CFD) framework to serve as a numerical tool for understanding and clarifying the impact of operating parameters on coating efficiency. It presents an overview of fluidized bed coating and its principles. The chapter covers the multiphase flow modeling approaches. Furthermore, CFD descriptions of mechanisms taking place in a top-spray fluidized bed coating process are presented. Fluidized particle hydrodynamics as affected by the fluidizing airflow are modeled by means of a Eulerian–Eulerian approach in which all phases, including gas and solids, penetrate each other and are incorporated with the concept of phase volume fraction. In this approach, all conservative equations are solved for each phase, resulting in a set of equations for each phase.
