Transient aerodynamic atomization model to predict aerosol droplet size of pressurized metered dose inhalers (pMDI)

Figures & data

Figure 1. Schematic of droplet generation from cylindrical liquid jet, using Reitz and Bracco (1986) atomization model in pMDI.

Figure 2. Schematic of droplet generation from annular liquid sheet, using LISA mechanism (Senecal et al. 1999) in pMDI.

Figure 3. Schematic of spray development in near-orifice region immediately downstream from spray orifice in choked conditions, illustrating propellant flashing and associated droplet size reduction.

Figure 4. Prediction of spray droplet size compared with PDA measurements of Myatt et al. (2015a,b) (test case parameters in Table S1). (a) HFA134a; (b) HFA227.

Figure 5. Comparison of predicted spray droplet size against PDA measurements of Dunbar et al. (1997).

Figure 6. Comparison of predicted spray droplet size against PDA measurements of Wigley et al. (2002).

Figure 7. Ratios of near-orifice droplet size (after flashing) and spray orifice droplet size (before flashing) for modeling parameters of Myatt et al. (2015a,b), using HFA134a.

Figure 8. Predictions of wavelength of most unstable disturbance and droplet size for inviscid/viscous sheet and jet models, corresponding to test case in Table S1 using HFA134a propellant (a) wave length (b) droplet size.

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