Abstract View
Droplet Deposition Measurements in a Simplified Mouth-Throat Airway
HUIZHEN YANG, Xiaole Chen, Ting Ding, Jinan Zhang, Nanjing Normal University
Abstract Number: 67
Working Group: Health-Related Aerosols
Abstract
Portable vibrating mesh nebulizer now becomes an alternative approach generating drug aerosols for the treatment of pulmonary diseases. Its compliance of children and infants is relatively better than injection and oral administration. Experiments carried out using a simplified mouth-throat (MT) airway model under different inhalation flow rate conditions explored the deposition fraction (DF) of droplets. The normal saline droplets were generated from a portable vibrating mesh nebulizer (Youwell HL100A). The experiment system consisted of the VMN, MT airway, a filtration unit, and a vacuum pump. After each droplet deposition test, the MT airway and the filter were washed with distilled water using ultrasonic cleaning. The washed-out solutions were prepared in volumetric flasks, and then the sodium chloride (NaCl) concentrations were measured. Therefore, the droplet DF could be determined. The droplet DFs were measured under different inhalation flow rates, i.e., 15, 22.5, 30, 45, and 60 L/min. The environment of the experiments was controlled at T=26.5°C, RH=50% and PM2.5 = 0 μg/m3. The results indicate that the DF of the droplet does not increase with the increase of the inhalation flow rate, which is different from the dry particle experiments in literature. The DF of the droplets decreases from 25.7% at 15 L/min to 7.3% at 22.5 L/min, and further declines to 6.8% at 30 L/min. Then the DF of the droplets gradually increases from 13.8% at 45 L/min to 14.5% at 60L/min. The high DFs of the droplets at the low inhalation flow rates, i.e., 15 L/min and 22.5 L/min, may relate to the droplet evaporation process in the airway.