Turbulent flow energy for aerosolization of powder particles
نویسندگان
چکیده
The process of re-entrainment and re-dispersion of powder particles is studied both theoretically and experimentally in order to discuss the possibilities of improvement of the quality of aerosol emitted from dry powder inhalers (DPI). The eddy fluid particle model (EFPM) is employed to solve turbulent flow structure in the microscale in a channel with various types of turbulence promoters. The resuspension process caused by the gas shearing forces is modeled with the Verlet algorithm taking into account the inter-particle cohesive interactions. Nondimensional numbers are introduced to define the domains of powder aerosolization. Computational results indicate the importance of the geometry of turbulence promoters for powder re-entrainment (fluidization) and de-aggregation of particle clusters. The theoretical findings, are supported by experimental results obtained in a model resuspension chamber with a pharmaceutical powder (disodium cromoglycate). A noticeable increase of emission and re-dispersion was obtained at low airflow rates due to the use of turbulence promoters mounted in the vicinity of the powder layer. The corresponding increase of flow resistance is acceptable in respect to the practical application in DPIs. 2007 Elsevier Ltd. All rights reserved.
منابع مشابه
The following manuscript entitled “An investigation into the effect of fine lactose particles on the fluidization behaviour and aerosolization performance of carrier-based dry powder inhaler formulations” has been published in AAPS PharmSciTech 2014 Aug;15(4):898-909
The effect of milled and micronized lactose fines on the fluidization and in vitro aerosolization properties of dry powder inhaler (DPI) formulations was investigated, and the suitability of static and dynamic methods for characterising general powder flow properties of these blends was assessed. Lactose carrier pre-blends were prepared by adding different lactose fines (Lactohale 300, 230 and ...
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