Author, as appears in the article.: Pallares J; Fabregat A; Cito S
Department: Enginyeria Mecànica
URV's Author/s: Cito, Salvatore / Fabregat Tomàs, Alexandre / Pallarés Curto, Jorge María
Keywords: Unsteady jet Turbulent puff Turbulent dispersion Transport Particle dispersion Large-eddy simulation Expiratory event unsteady jet turbulent puff turbulent dispersion particle dispersion large-eddy simulation aerosols
Abstract: In the wake of the COVID-19 pandemic, interest in understanding the turbulent dispersion of airborne pathogen-laden particles has significantly increased. The ability of infectious particles to stay afloat and disperse in indoor environments depends on their size, the environmental conditions and the hydrodynamics of the flow generated by the exhalation. In this work we analyze the impact of three different aspects, namely, the buoyancy force, the upper airways geometry and the head rotation during the exhalation on the short-term dispersion. Large-Eddy Simulations have been used to assess the impact of each separate effect on the thermal puff and particle cloud evolution over the first 2 s after the onset of the exhalation. Results obtained during this short-term period suggest that due to the rapid mixing of the turbulent puff, buoyancy forces play a moderate role on the ability of the particles to disperse. Because of the enhanced mixing, buoyancy reduces the range and increases the vertical size of the small particle clouds. In comparison to the fixed frame case, head rotation has been found to notably affect the size and shape of the cloud by enhancing the vertical transport as the exhalation axial direction sweeps vertically during the exhalation. The impact of the upper airway geometry, in comparison to an idealized mouth consisting in a pipe of circular section, has been found to be the largest when it is considered along with the head rotation.
Thematic Areas: Química Pollution Meteorology & atmospheric sciences Mechanical engineering Materials science (miscellaneous) General materials science Fluid flow and transfer processes Environmental sciences Environmental engineering Environmental chemistry Engineering, mechanical Engineering, chemical Atmospheric science
licence for use: https://creativecommons.org/licenses/by/3.0/es/
Author's mail: alexandre.fabregat@urv.cat jordi.pallares@urv.cat salvatore.cito@urv.cat
Author identifier: 0000-0002-6032-2605 0000-0003-0305-2714 0000-0001-7626-3374
Record's date: 2023-02-23
Papper version: info:eu-repo/semantics/publishedVersion
Link to the original source: https://www.sciencedirect.com/science/article/pii/S0021850222000908
Licence document URL: http://repositori.urv.cat/ca/proteccio-de-dades/
Papper original source: Journal Of Aerosol Science. 166 106052-
APA: Pallares J; Fabregat A; Cito S (2022). Effects of upper respiratory tract anatomy and head movement on the buoyant flow and particle dispersion generated in a violent expiratory event. Journal Of Aerosol Science, 166(), 106052-. DOI: 10.1016/j.jaerosci.2022.106052
Article's DOI: 10.1016/j.jaerosci.2022.106052
Entity: Universitat Rovira i Virgili
Journal publication year: 2022
Publication Type: Journal Publications
Repositori URV