{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,31]],"date-time":"2026-07-31T21:30:43Z","timestamp":1785533443458,"version":"3.56.0"},"reference-count":55,"publisher":"AIP Publishing","issue":"10","funder":[{"DOI":"10.13039\/501100001849","name":"Defence Research and Development Organisation","doi-asserted-by":"publisher","award":["0707"],"award-info":[{"award-number":["0707"]}],"id":[{"id":"10.13039\/501100001849","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":["pubs.aip.org"],"crossmark-restriction":true},"short-container-title":[],"published-print":{"date-parts":[[2021,10,1]]},"abstract":"<jats:p>In majority of pandemics in human history, respiratory bio-aerosol is the most common route of transmission of diseases. These tiny droplets ejected through mouth and nose from an infected person during exhalation process like coughing, sneezing, speaking, and breathing consist of pathogens and a complex mixture of volatile and nonvolatile substances. A cloud of droplets ejected in such an event gets transmitted in the air, causing a series of coupled thermo-physical processes. Contemplating an individual airborne droplet in the cloud, boundary layers and wakes develop due to relative motion between the droplet and the ambient air. The complex phenomenon of the droplet's dynamics, such as shear-driven internal circulation of the liquid phase and Stefan flow due to vaporization or condensation, comes into effect. In this study, we present a mathematical description of the coupled subprocesses, including droplet aerodynamics, heat, and mass transfer, which were identified and subsequently solved. The presented two-dimensional model gives a complete analysis encompassing the gas phase coupled with the liquid phase responsible for the airborne droplet kinetics in the ambient environment. The transient inhomogeneity of temperature and concentration distribution in the liquid phase caused due to the convective and diffusive transports are captured in the 2D model. The evaporation time and distance traveled by droplets prior to nuclei or aerosol formation are computed for major geographical locations around the globe for nominal-windy conditions. The model presented can be used for determining the evaporation timescale of any viral or bacterial laden respiratory droplets across any geographical location.<\/jats:p>","DOI":"10.1063\/5.0064635","type":"journal-article","created":{"date-parts":[[2021,10,1]],"date-time":"2021-10-01T10:58:02Z","timestamp":1633085882000},"update-policy":"https:\/\/doi.org\/10.1063\/aip-crossmark-policy-page","source":"Crossref","is-referenced-by-count":12,"title":["Two-dimensional mathematical framework for evaporation dynamics of respiratory droplets"],"prefix":"10.1063","volume":"33","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-6128-3890","authenticated-orcid":false,"given":"Sreeparna","family":"Majee","sequence":"first","affiliation":[{"name":"Department of Mechanical Engineering, Indian Institute of Science 1 , Bengaluru, Karnataka 560012,","place":["India"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9619-6623","authenticated-orcid":false,"given":"Abhishek","family":"Saha","sequence":"additional","affiliation":[{"name":"Department of Mechanical and Aerospace Engineering, University of California San Diego 2 , La Jolla, California 92093,","place":["USA"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4109-8633","authenticated-orcid":false,"given":"Swetaprovo","family":"Chaudhuri","sequence":"additional","affiliation":[{"name":"Institute for Aerospace Studies, University of Toronto 3 , Toronto, Ontario M3H 5T6,","place":["Canada"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7838-5145","authenticated-orcid":false,"given":"Dipshikha","family":"Chakravortty","sequence":"additional","affiliation":[{"name":"Department of Microbiology and Cell Biology, Indian Institute of Science 4 , Bengaluru, Karnataka 560012,","place":["India"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9652-9966","authenticated-orcid":false,"given":"Saptarshi","family":"Basu","sequence":"additional","affiliation":[{"name":"Department of Mechanical Engineering, Indian Institute of Science 1 , Bengaluru, Karnataka 560012,","place":["India"]}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"317","published-online":{"date-parts":[[2021,10,1]]},"reference":[{"key":"2025052815265106800_c1","unstructured":"World Health Organization, \u201c\nModes of transmission of virus causing COVID-19: Implications for IPC precaution recommendations: Scientific brief, 27 March 2020,\u201d Technical Report No. 335867 (\nWorld Health Organization, 2020); available at https:\/\/apps.who.int\/iris\/handle\/10665\/331601."},{"key":"2025052815265106800_c2","doi-asserted-by":"publisher","first-page":"109819","DOI":"10.1016\/j.envres.2020.109819","article-title":"Transmission of COVID-19 virus by droplets and aerosols: A critical review on the unresolved dichotomy","volume":"188","year":"2020","journal-title":"Environ. 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