Predominance of inhalation route in short-range transmission of respiratory viruses:Investigation based on computational fluid dynamics  

作　　者：Wenzhao Chen Li Liu Jian Hang Yuguo Li 

机构地区：[1]Department of Mechanical Engineering,The University of Hong Kong,Pokfulam Road,Hong Kong,China [2]Department of Building Science,Tsinghua University,Beijing 100084,China [3]School of Atmospheric Sciences,Sun Yat-sen University,and Southern Marine Science and Engineering Guangdong Laboratory(Zhuhai),Zhuhai 519082,China [4]Faculty of Architecture,The University of Hong Kong,Pokfulam Road,Hong Kong,China

出　　处：《Building Simulation》2023年第5期765-780,共16页建筑模拟（英文）

基　　金：supported by a General Research Fund(grant number 17202719)provided by the Research Grants Council of Hong Kong.

摘　　要：During the coronavirus disease 2019 pandemic,short-range virus transmission has been observed to have a higher risk of causing infection than long-range virus transmission.However,the roles played by the inhalation and large droplet routes cannot be distinguished in practice.A recent analytical study revealed the predominance of short-range inhalation over the large droplet spray route as causes of respiratory infections.In the current study,short-range exposure was analyzed via computational fluid dynamics(CFD)simulations using a discrete phase model.Detailed facial membranes,including eyes,nostrils,and a mouth,were considered.In CFD simulations,there is no need for a spherical approximation of the human head for estimating deposition nor the“anisokinetic aerosol sampling”approximation for estimating inhalation in the analytical model.We considered two scenarios(with two spheres[Scenario 1]and two human manikins[Scenario 2]),source-target distances of 0.2 to 2 m,and droplet diameters of 3 to 1,500μm.The overall CFD exposure results agree well with data previously obtained from a simple analytical model.The CFD results confirm the predominance of the short-range inhalation route beyond 0.2 m for expiratory droplets smaller than 50μm during talking and coughing.A critical droplet size of 87.5μm was found to differentiate droplet behaviors.The number of droplets deposited on the target head exceeded those exposed to facial membranes,which implies a risk of exposure through the immediate surface route over a short range.

关 键 词：airborne transmission close contact short-range inhalation large droplet spray computational fluid dynamics 

分 类 号：O35[理学—流体力学]