Aerosol transport in a model of human lungs

¹ Brno University of Technology, Faculty of Mechanical Engineering, Technicka 2, 616 69 Brno, Czech Republic
ylizal00@stud.fme.vutbr.cz
² Brno University of Technology, Faculty of Chemistry, Purkynova 118, 612 00 Brno, Czech Republic
xchalasova@fch.vutbr.cz

Abstract

Complex flow structures emerging in human lungs significantly affect deposition of inhaled particles. Therefore flow measurements alongside with deposition measurements have to be performed on the same model geometry. Amount of deposited aerosol particles in different regions of lungs could be measured by several methods. Gamma detection of radioactive tagged particles is subjected to strict regulations and is expensive; gravimetry and fluorometry are thus preferred in current studies.

Novel methodology for fluorometric measurement of aerosol transport in models of human lungs was developed. Some previously published experiments were performed using condensation of di(2-ethylhexyl) sebacate (DEHS) vapours on fluorescein nuclei. Their authors assumed that fluorescein is necessary for generation of fluorescent particles and they neglected possible fluorescence of DEHS itself. Our analysis of DEHS characteristics indicated that DEHS fluorescence could be detected apart in sufficient rate to evaluate aerosol deposition. Consequently experiments in standard setup of condensation monodisperse aerosol generator with sodium chloride nuclei instead of fluorescein were performed. Results demonstrating applicability and limitations of DEHS particles for fluorometric deposition measurements are presented and discussed.