[1] Gao Naiping, Niu Jianlei, Lidia Morawska,. Distribution characteristics of respiratory aerosolsin enclosed environments [J]. Journal of Southeast University (English Edition), 2010, 26 (2): 232-237. [doi:10.3969/j.issn.1003-7985.2010.02.019]

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Distribution characteristics of respiratory aerosolsin enclosed environments()

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Journal of Southeast University (English Edition)[ISSN:1003-7985/CN:32-1325/N]

Volumn:

26

Issue:

2010 2

Page:

232-237

Research Field:

Energy and Power Engineering

Publishing date:

2010-06-30

Info

Title:

Distribution characteristics of respiratory aerosolsin enclosed environments

Author(s):

Gao Naiping¹;  Niu Jianlei²;  Lidia Morawska³

¹College of Mechanical Engineering, Tongji University, Shanghai 200092, China
²Department of Building Services Engineering, the Hong Kong Polytechnic University, Hong Kong, China
³School of Physical and Chemical Sciences, Queensland University of Technology, Queensland, Australia

Keywords:

respiratory droplets;  displacement ventilation;  under-floor air distribution(UFAD);  transmission;  airborne disease

PACS:

TU834

DOI:

10.3969/j.issn.1003-7985.2010.02.019

Abstract:

This paper studies the spatial concentration distribution and temporal evolution of exhaled and sneezed/coughed droplets within the range of 1.0 to 10.0 μm in an office room with three air distribution methods, including mixing ventilation(MV), displacement ventilation(DV), and under-floor air distribution(UFAD).The simulation results indicate that exhaled droplets with diameters up to 10.0 μm from normal respiration process are uniformly distributed in MV.However, they become trapped at the breathing height by thermal stratifications in DV and UFAD, resulting in a high droplet concentration and an increased exposure risk to other occupants.Sneezed/coughed droplets are more slowly diluted in DV/UFAD than in MV.Low air speed in the breathing zone in DV/UFAD can lead to prolonged human exposure to droplets in the breathing zone.

References:

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Memo

Memo:

Biography: Gao Naiping(1978—), male, doctor, associate professor, gaonaiping@tongji.edu.cn.
Foundation items: The National Natural Science Foundation of China(No.50808133), the Dean’s Reserve of Faculty of Construction and Land Use at the Hong Kong Polytechnic University.
Citation: Gao Naiping, Niu Jianlei, Lidia Morawska.Distribution characteristics of respiratory aerosols in enclosed environments[J].Journal of Southeast University(English Edition), 2010, 26(2):232-237.

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