Popis: |
An integrated computational model of a commercial Dry Powder Inhaler, DPI, device (i.e., Turbuhaler) is developed. The steady-state flow in a DPI is determined by solving the Navier-Stokes equations using FLUENT (v6.3) considering different flow models, e.g., laminar, k-e, k-ω SST. Particle motion and deposition are described using an Eulerian-fluid/Lagrangian-particle approach. Particle/wall collisions are taken to result in deposition when the normal collision velocity is less than a size-dependent critical value. The flow rate and particle deposition are determined for a range of pressure drops (i.e., 800-8800Pa), as well as particle sizes corresponding to single particles and aggregates (i.e., 0.5-20μm). Overall, the simulation results are found to agree well with available experimental data for the volumetric outflow rate as well as the local and total particle deposition. |