Measurements of Aerosol Particle Sizes from a Direct Injection Nebulizer

Photographs and laser-scattering measurements showed that a direct injection nebulizer (DIN) produced a finer aerosol with a narrower drop size distribution than that for a conventional glass concentric nebulizer when both were operated at the same liquid and nebulizer gas flow rates. The droplets from the DIN were slightly larger, however, than those leaving a Scott-type spray chamber with a glass concentric nebulizer. The droplets from the DIN had a Sauter mean diameter of ∼7 μm and a 90% mass diameter of 11–16 μm. The droplet size distribution became narrower and shifted to lower diameters as the aerosol gas flow rate increased.