File Download

There are no files associated with this item.

  Links for fulltext
     (May Require Subscription)
Supplementary

Article: How far droplets can move in indoor environments - revisiting the Wells evaporation-falling curve

TitleHow far droplets can move in indoor environments - revisiting the Wells evaporation-falling curve
Authors
Issue Date2007
PublisherBlackwell Munksgaard. The Journal's web site is located at http://www.blackwellpublishing.com/journals/INA
Citation
Indoor Air, 2007, v. 17 n. 3, p. 211-225 How to Cite?
AbstractA large number of infectious diseases are believed to be transmitted between people via large droplets and by airborne routes. An understanding of evaporation and dispersion of droplets and droplet nuclei is not only significant for developing effective engineering control methods for infectious diseases but also for exploring the basic transmission mechanisms of the infectious diseases. How far droplets can move is related to how far droplet-borne diseases can transmit. A simple physical model is developed and used here to investigate the evaporation and movement of droplets expelled during respiratory activities; in particular, the well-known Wells evaporation-falling curve of droplets is revisited considering the effect of relative humidity, air speed, and respiratory jets. Our simple model considers the movement of exhaled air, as well as the evaporation and movement of a single droplet. Exhaled air is treated as a steady-state non-isothermal (warm) jet horizontally issuing into stagnant surrounding air. A droplet is assumed to evaporate and move in this non-isothermal jet. Calculations are performed for both pure water droplets and droplets of sodium chloride (physiological saline) solution (0.9% w/v). We calculate the droplet lifetimes and how droplet size changes, as well as how far the droplets travel in different relative humidities. Our results indicate that a droplet's size predominately dictates its evaporation and movement after being expelled. The sizes of the largest droplets that would totally evaporate before falling 2 m away are determined under different conditions. The maximum horizontal distances that droplets can reach during different respiratory activities are also obtained. Our study is useful for developing effective prevention measures for controlling infectious diseases in hospitals and in the community at large. © 2007 The Authors Journal compilation 2007 Blackwell Munksgaard.
Persistent Identifierhttp://hdl.handle.net/10722/157482
ISSN
2015 Impact Factor: 4.33
2015 SCImago Journal Rankings: 1.666
ISI Accession Number ID
References

 

DC FieldValueLanguage
dc.contributor.authorXie, Xen_US
dc.contributor.authorLi, Yen_US
dc.contributor.authorChwang, ATYen_US
dc.contributor.authorHo, PLen_US
dc.contributor.authorSeto, WHen_US
dc.date.accessioned2012-08-08T08:50:24Z-
dc.date.available2012-08-08T08:50:24Z-
dc.date.issued2007en_US
dc.identifier.citationIndoor Air, 2007, v. 17 n. 3, p. 211-225en_US
dc.identifier.issn0905-6947en_US
dc.identifier.urihttp://hdl.handle.net/10722/157482-
dc.description.abstractA large number of infectious diseases are believed to be transmitted between people via large droplets and by airborne routes. An understanding of evaporation and dispersion of droplets and droplet nuclei is not only significant for developing effective engineering control methods for infectious diseases but also for exploring the basic transmission mechanisms of the infectious diseases. How far droplets can move is related to how far droplet-borne diseases can transmit. A simple physical model is developed and used here to investigate the evaporation and movement of droplets expelled during respiratory activities; in particular, the well-known Wells evaporation-falling curve of droplets is revisited considering the effect of relative humidity, air speed, and respiratory jets. Our simple model considers the movement of exhaled air, as well as the evaporation and movement of a single droplet. Exhaled air is treated as a steady-state non-isothermal (warm) jet horizontally issuing into stagnant surrounding air. A droplet is assumed to evaporate and move in this non-isothermal jet. Calculations are performed for both pure water droplets and droplets of sodium chloride (physiological saline) solution (0.9% w/v). We calculate the droplet lifetimes and how droplet size changes, as well as how far the droplets travel in different relative humidities. Our results indicate that a droplet's size predominately dictates its evaporation and movement after being expelled. The sizes of the largest droplets that would totally evaporate before falling 2 m away are determined under different conditions. The maximum horizontal distances that droplets can reach during different respiratory activities are also obtained. Our study is useful for developing effective prevention measures for controlling infectious diseases in hospitals and in the community at large. © 2007 The Authors Journal compilation 2007 Blackwell Munksgaard.en_US
dc.languageengen_US
dc.publisherBlackwell Munksgaard. The Journal's web site is located at http://www.blackwellpublishing.com/journals/INAen_US
dc.relation.ispartofIndoor Airen_US
dc.subject.meshAir Movementsen_US
dc.subject.meshAir Pollutantsen_US
dc.subject.meshAir Pollution, Indooren_US
dc.subject.meshCommunicable Disease Controlen_US
dc.subject.meshCommunicable Diseases - Transmissionen_US
dc.subject.meshCoughen_US
dc.subject.meshExhalationen_US
dc.subject.meshHumansen_US
dc.subject.meshHumidityen_US
dc.subject.meshModels, Theoreticalen_US
dc.subject.meshSneezingen_US
dc.subject.meshSodium Chlorideen_US
dc.subject.meshWateren_US
dc.titleHow far droplets can move in indoor environments - revisiting the Wells evaporation-falling curveen_US
dc.typeArticleen_US
dc.identifier.emailLi, Y: liyg@HKUCC.hku.hken_US
dc.identifier.emailChwang, ATY: atchwang@hkucc.hku.hk-
dc.identifier.emailHo, PL: plho@hkucc.hku.hk-
dc.identifier.emailSeto, WH: whseto@HKUCC.hku.hk-
dc.identifier.authorityHo, PL=rp00406en_US
dc.description.naturelink_to_subscribed_fulltexten_US
dc.identifier.doi10.1111/j.1600-0668.2007.00469.xen_US
dc.identifier.pmid17542834-
dc.identifier.scopuseid_2-s2.0-34249703515en_US
dc.identifier.hkuros134414-
dc.relation.referenceshttp://www.scopus.com/mlt/select.url?eid=2-s2.0-34249703515&selection=ref&src=s&origin=recordpageen_US
dc.identifier.volume17en_US
dc.identifier.issue3en_US
dc.identifier.spage211en_US
dc.identifier.epage225en_US
dc.identifier.isiWOS:000247600500005-
dc.publisher.placeDenmarken_US
dc.identifier.scopusauthoridXie, X=14627859000en_US
dc.identifier.scopusauthoridLi, Y=36012284100en_US
dc.identifier.scopusauthoridChwang, ATY=7005883964en_US
dc.identifier.scopusauthoridHo, PL=7402211363en_US
dc.identifier.scopusauthoridSeto, WH=35293452400en_US
dc.identifier.citeulike1353737-
dc.customcontrol.immutablesml 130529-

Export via OAI-PMH Interface in XML Formats


OR


Export to Other Non-XML Formats