Journal of Aerosol Science | 2021
Numerical study of effects of device design on drug delivery efficiency for an active dry powder inhaler
Abstract
Abstract Active dry powder inhalers (DPIs) actuated by low air volume provide distinct advantages for delivering aerosols to patients with poor respiratory capacity. This work aims to investigate the effects of piercing aperture location and inlet flow rate on device-emptying, and to identify the mechanism of particle deposition in a realistic mouth-throat (MT) region. Computational fluid dynamics (CFD) is employed to predict dispersion parameters that measure turbulence intensity, and mono-sized particles are tracked by the discrete phase model (DPM). Results show that the piercing aperture location and the inlet flow rate both have significant impacts on device emptying. Strong correlations have been established between the emitted dose and flow field parameters. The pattern and distribution of the deposited particles in the realistic MT region are highly sensitive to particle size, flow rate and reservoir length. This work provides profound insights into the performance of the active DPIs and an additional perspective on device design.