Simulation of aerosol nucleation and growth in a turbulent mixing layer

Handle URI:
http://hdl.handle.net/10754/552125
Title:
Simulation of aerosol nucleation and growth in a turbulent mixing layer
Authors:
Zhou, Kun ( 0000-0003-2320-3655 ) ; Attili, Antonio; Alshaarawi, Amjad ( 0000-0002-2350-3300 ) ; Bisetti, Fabrizio ( 0000-0001-5162-7805 )
Abstract:
A large-scale simulation of aerosol nucleation and growth in a turbulent mixing layer is performed and analyzed with the aim of elucidating the key processes involved. A cold gaseous stream is mixed with a hot stream of vapor, nanometer sized droplets nucleate as the vapor becomes supersaturated, and subsequently grow as more vapor condenses on their surface. All length and time scales of fluid motion and mixing are resolved and the quadrature method of moments is used to describe the dynamics of the condensing, non-inertial droplets. The results show that a region of high nucleation rate is located near the cold, dry stream, while particles undergo intense growth via condensation on the hot, humid vapor side. Supersaturation and residence times are such that number densities are low and neither coagulation nor vapor scavenging due to condensation are significant. The difference in Schmidt numbers of aerosol particles (approximated as infinity) and temperature and vapor (near unity) causes a drift of the aerosol particles in scalar space and contributes to a large scatter in the conditional statistics of aerosol quantities. The spatial distribution of the aerosol reveals high volume fraction on the hot side of the mixing layer. This distribution is due to drift against the mean and is related to turbulent mixing, which displaces particles from the nucleation region (cold side) into the growth region (hot side). Such a mechanism is absent in laminar flows and is a distinct feature of turbulent condensing aerosols.
KAUST Department:
Clean Combustion Research Center
Citation:
Simulation of aerosol nucleation and growth in a turbulent mixing layer 2014, 26 (6):065106 Physics of Fluids
Journal:
Physics of Fluids
Issue Date:
25-Jun-2014
DOI:
10.1063/1.4884789
Type:
Article
ISSN:
1070-6631; 1089-7666
Additional Links:
http://scitation.aip.org/content/aip/journal/pof2/26/6/10.1063/1.4884789
Appears in Collections:
Articles; Clean Combustion Research Center

Full metadata record

DC FieldValue Language
dc.contributor.authorZhou, Kunen
dc.contributor.authorAttili, Antonioen
dc.contributor.authorAlshaarawi, Amjaden
dc.contributor.authorBisetti, Fabrizioen
dc.date.accessioned2015-05-03T13:55:03Zen
dc.date.available2015-05-03T13:55:03Zen
dc.date.issued2014-06-25en
dc.identifier.citationSimulation of aerosol nucleation and growth in a turbulent mixing layer 2014, 26 (6):065106 Physics of Fluidsen
dc.identifier.issn1070-6631en
dc.identifier.issn1089-7666en
dc.identifier.doi10.1063/1.4884789en
dc.identifier.urihttp://hdl.handle.net/10754/552125en
dc.description.abstractA large-scale simulation of aerosol nucleation and growth in a turbulent mixing layer is performed and analyzed with the aim of elucidating the key processes involved. A cold gaseous stream is mixed with a hot stream of vapor, nanometer sized droplets nucleate as the vapor becomes supersaturated, and subsequently grow as more vapor condenses on their surface. All length and time scales of fluid motion and mixing are resolved and the quadrature method of moments is used to describe the dynamics of the condensing, non-inertial droplets. The results show that a region of high nucleation rate is located near the cold, dry stream, while particles undergo intense growth via condensation on the hot, humid vapor side. Supersaturation and residence times are such that number densities are low and neither coagulation nor vapor scavenging due to condensation are significant. The difference in Schmidt numbers of aerosol particles (approximated as infinity) and temperature and vapor (near unity) causes a drift of the aerosol particles in scalar space and contributes to a large scatter in the conditional statistics of aerosol quantities. The spatial distribution of the aerosol reveals high volume fraction on the hot side of the mixing layer. This distribution is due to drift against the mean and is related to turbulent mixing, which displaces particles from the nucleation region (cold side) into the growth region (hot side). Such a mechanism is absent in laminar flows and is a distinct feature of turbulent condensing aerosols.en
dc.relation.urlhttp://scitation.aip.org/content/aip/journal/pof2/26/6/10.1063/1.4884789en
dc.rightsArchived with thanks to Physics of Fluids. © 2014 AIP Publishing LLC .[ http://dx.doi.org/10.1063/1.4884789 ]en
dc.titleSimulation of aerosol nucleation and growth in a turbulent mixing layeren
dc.typeArticleen
dc.contributor.departmentClean Combustion Research Centeren
dc.identifier.journalPhysics of Fluidsen
dc.eprint.versionPublisher's Version/PDFen
kaust.authorZhou, Kunen
kaust.authorAttili, Antonioen
kaust.authorBisetti, Fabrizioen
kaust.authorAlshaarawi, Amjaden
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