Go Back to Publications

Fluidized processor for pharmaceutical application

Effective operation of fluidized bed processors requires a uniform gas distribution and good mixing of particles. Scaling up a !uidized bed process from lab scale to production-scale presents unique chal- lenges such as preventing granule attrition, "nes loss, or segregation. In addition, current methods make it dif"cult to optimize processor performance without large-scale experimentation due to the scale dependence of in!uences on the !uidization and related effects on the !uidized particle. Fluidization behavior is dependent on the reac- tor geometry and internals as well as the particle size distribution and physical properties of the powder. To accurately simulate !uidized bed behavior, it is necessary to choose a numerical method capable of accounting not only for the particle–!uid effects (e.g., drag) but also for particle–wall impacts and particle–particle interactions in three dimensions and across the entire particle size distribution.

The objective of this work was to perform a “blind test” comparison of the Barracuda® commercial computational !uid dynamics (CFD) software package from CPFD Software, LLC (Albuquerque, NM) for the modeling of !uidized bed processors. Barracuda rigorously simulates !uid–particle interactions in three-dimensions using the CPFD® nu- merical method by Snider [1,2] and O'Rourke et al. [3] and is an established commercial simulation software package for the study of research-scale and industrial-scale !uidized bed reactors by Zhao et al. [4], Snider et al. [5], and Parker [6]. No experimental results were shared with the CFD analyst until the simulations had been completed.