Transport Modeling of Micron-Sized Particles in Different Geometries Using a Two-Fluid Eulerian-Eulerian Approach

This paper examines a unified, two-fluid Eulerian-Eulerian modeling approach, in which a concentration equation was solved for micron-sized particles.  In addition, a particle phase momentum equation was solved to determine the particle bulk velocities, separate from the air velocity.  Results were compared to the more traditional approach of Eulerian-Lagrangian particle-tracking method and to experimental data to evaluate the performance of the Eulerian-Eulerian method.  Steady state flow was considered through a 90^o bend (elbow) and a physiological realistic bifurcation (PRB) geometries.  PRB results are a representative idealized lung airway model consisting of three physiologically realistic airway branch bifurcations.  Simulations were performed using the commercial computational fluid dynamics (CFD) code FLUENT, and the particle phase equations were implemented using user-defined function (UDF) subroutines.  The effects of boundary conditions, mesh resolution, mesh topology, and particle size were evaluated.  Results suggest that the unified Eulerian-Eulerian method is an effective approach for particle transport simulations with particle deposition results that match well with the experimental data.