(150b) Toward Simulation-Based Design of Particle Handling Processes

Authors: 
Curtis, J. S., UC Davis
Particulate processes pervade the petroleum, chemical, mining, pharmaceutical, and agricultural industries. Many of these processes have significant opportunities for optimization and productivity enhancements. Reliable particle modeling and simulation tools can improve critical understanding and design of particle transport processes; this talk will provide several examples in this regard. A recent approach to modeling particle flow employs the discrete element method (DEM). In DEM, the dynamics of individual powder particles are described rather than treating the particle phase as a continuum via CFD. DEM models are especially useful for investigating phenomena occurring at the particle-length scale. Although DEM models are computationally intensive, they are capable of developing constitutive relations for the particle phase that are needed for continuum-based CFD simulations.

Specifically, this presentation will focus on DEM modeling of complex particulate flows for non-spherical particles which are described via linked and overlapping spheres. In addition, both rigid and flexible non-spherical particles, including particle breakage, will be discussed. Finally, we consider the effect of cohesion of non-spherical particles via liquid bridging. The particle models are validated via experiments - shear cells testing, angle of repose testing, hopper discharge, particle packing, and particle breakage due to compaction and flow in a FT4 rheometer. These aspects of particle flow (asphericity, flexibility, breakage and cohesion) are of great importance in many practical applications and, hence, are the subjects of research at the forefront of current particle modeling efforts.