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Title: Speech can produce jet-like transport relevant to asymptomatic spreading of virus
Significance Medical reports and news sources raise the possibility that flows created during breathing, speaking, laughing, singing, or exercise could be the means by which asymptomatic individuals contribute to spread of the SARS-CoV-2 virus. We use experiments and simulations to quantify how exhaled air is transported in speech. Phonetic characteristics introduce complexity to the airflow dynamics and plosive sounds, such as “P,” produce intense vortical structures that behave like “puffs” and rapidly reach 1 m. However, speech, corresponding to a train of such puffs, creates a conical, turbulent, jet-like flow and easily produces directed transport over 2 m in 30 s of conversation. This work should inform public health guidance for risk reduction and mitigation strategies of airborne pathogen transmission.  more » « less
Award ID(s):
2029370
PAR ID:
10194524
Author(s) / Creator(s):
 ;  ;  ;  ;  
Publisher / Repository:
Proceedings of the National Academy of Sciences
Date Published:
Journal Name:
Proceedings of the National Academy of Sciences
Volume:
117
Issue:
41
ISSN:
0027-8424
Format(s):
Medium: X Size: p. 25237-25245
Size(s):
p. 25237-25245
Sponsoring Org:
National Science Foundation
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