Cargando…
Role of pulsatility on particle dispersion in expiratory flows
Expiratory events, such as coughs, are often pulsatile in nature and result in vortical flow structures that transport respiratory particles. In this work, direct numerical simulation (DNS) of turbulent pulsatile jets, coupled with Lagrangian particle tracking of micron-sized droplets, is performed...
Autores principales: | , , , , |
---|---|
Formato: | Online Artículo Texto |
Lenguaje: | English |
Publicado: |
AIP Publishing LLC
2021
|
Materias: | |
Acceso en línea: | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8060012/ https://www.ncbi.nlm.nih.gov/pubmed/33897248 http://dx.doi.org/10.1063/5.0048746 |
_version_ | 1783681280321257472 |
---|---|
author | Monroe, K. Yao, Y. Lattanzi, A. Raghav, V. Capecelatro, J. |
author_facet | Monroe, K. Yao, Y. Lattanzi, A. Raghav, V. Capecelatro, J. |
author_sort | Monroe, K. |
collection | PubMed |
description | Expiratory events, such as coughs, are often pulsatile in nature and result in vortical flow structures that transport respiratory particles. In this work, direct numerical simulation (DNS) of turbulent pulsatile jets, coupled with Lagrangian particle tracking of micron-sized droplets, is performed to investigate the role of secondary and tertiary expulsions on particle dispersion and penetration. Fully developed turbulence obtained from DNS of a turbulent pipe flow is provided at the jet orifice. The volumetric flow rate at the orifice is modulated in time according to a damped sine wave, thereby allowing for control of the number of pulses, duration, and peak amplitude. Thermodynamic effects, such as evaporation and buoyancy, are neglected in order to isolate the role of pulsatility on particle dispersion. The resulting vortex structures are analyzed for single-, two-, and three-pulse jets. The evolution of the particle cloud is then compared to existing single-pulse models. Particle dispersion and penetration of the entire cloud are found to be hindered by increased pulsatility. However, the penetration of particles emanating from a secondary or tertiary expulsion is enhanced due to acceleration downstream by vortex structures. |
format | Online Article Text |
id | pubmed-8060012 |
institution | National Center for Biotechnology Information |
language | English |
publishDate | 2021 |
publisher | AIP Publishing LLC |
record_format | MEDLINE/PubMed |
spelling | pubmed-80600122021-04-22 Role of pulsatility on particle dispersion in expiratory flows Monroe, K. Yao, Y. Lattanzi, A. Raghav, V. Capecelatro, J. Phys Fluids (1994) ARTICLES Expiratory events, such as coughs, are often pulsatile in nature and result in vortical flow structures that transport respiratory particles. In this work, direct numerical simulation (DNS) of turbulent pulsatile jets, coupled with Lagrangian particle tracking of micron-sized droplets, is performed to investigate the role of secondary and tertiary expulsions on particle dispersion and penetration. Fully developed turbulence obtained from DNS of a turbulent pipe flow is provided at the jet orifice. The volumetric flow rate at the orifice is modulated in time according to a damped sine wave, thereby allowing for control of the number of pulses, duration, and peak amplitude. Thermodynamic effects, such as evaporation and buoyancy, are neglected in order to isolate the role of pulsatility on particle dispersion. The resulting vortex structures are analyzed for single-, two-, and three-pulse jets. The evolution of the particle cloud is then compared to existing single-pulse models. Particle dispersion and penetration of the entire cloud are found to be hindered by increased pulsatility. However, the penetration of particles emanating from a secondary or tertiary expulsion is enhanced due to acceleration downstream by vortex structures. AIP Publishing LLC 2021-04 2021-04-12 /pmc/articles/PMC8060012/ /pubmed/33897248 http://dx.doi.org/10.1063/5.0048746 Text en © 2021 Author(s) Published under license by AIP Publishing. 1070-6631/2021/33(4)/043311/13/$30.00 https://creativecommons.org/licenses/by/4.0/All article content, except where otherwise noted, is licensed under a Creative Commons Attribution (CC BY) license (http://creativecommons.org/licenses/by/4.0/ (https://creativecommons.org/licenses/by/4.0/) ). |
spellingShingle | ARTICLES Monroe, K. Yao, Y. Lattanzi, A. Raghav, V. Capecelatro, J. Role of pulsatility on particle dispersion in expiratory flows |
title | Role of pulsatility on particle dispersion in expiratory flows |
title_full | Role of pulsatility on particle dispersion in expiratory flows |
title_fullStr | Role of pulsatility on particle dispersion in expiratory flows |
title_full_unstemmed | Role of pulsatility on particle dispersion in expiratory flows |
title_short | Role of pulsatility on particle dispersion in expiratory flows |
title_sort | role of pulsatility on particle dispersion in expiratory flows |
topic | ARTICLES |
url | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8060012/ https://www.ncbi.nlm.nih.gov/pubmed/33897248 http://dx.doi.org/10.1063/5.0048746 |
work_keys_str_mv | AT monroek roleofpulsatilityonparticledispersioninexpiratoryflows AT yaoy roleofpulsatilityonparticledispersioninexpiratoryflows AT lattanzia roleofpulsatilityonparticledispersioninexpiratoryflows AT raghavv roleofpulsatilityonparticledispersioninexpiratoryflows AT capecelatroj roleofpulsatilityonparticledispersioninexpiratoryflows |