Assessing impact of intermittent window opening strategies on pathogen-laden droplet dispersion in a coach bus  

作　　者：Qiqi Luo Xingdong Deng Jian Hang Cuiyun Ou Zhiwen Luo Xiaodan Fan Xia Yang Yifei Zhang Zhongli Gu Xuelin Zhang 

机构地区：[1]School of Atmospheric Sciences,Sun Yat-sen University,and Southern Marine Science and Engineering Guangdong Laboratory,Zhuhai 519082,China [2]Key Laboratory of Urban Meteorology,China Meteorological Administration,Beijing 100089,China [3]China Meteorological Administration Xiong'an Atmospheric Boundary Layer Key Laboratory,Xiong'an,China [4]Guangzhou Urban Planning&Design Survey Research Institute,Guangzhou 510060,China [5]Guangzhou Collaborative Innovation Center of Natural Resources Planning and Marine Technology,Guangzhou 510060,China [6]Guangdong Enterprise Key Laboratory for Urban Sensing,Monitoring and Early Warning,Guangzhou 510060,China [7]Welsh Schoolof Architecture,Cardiff University,UK [8]Guangdong Province Engineering Laboratory for Air Pollution Control,South China Institute of Environmental Sciences,the Ministry of Ecology and Environment of China,No.7 West Street Yuancun,Guangzhou 510655,China [9]Guangdong Fans-tech Agro Co.,Ltd,Guangdong Province,China

出　　处：《Building Simulation》2024年第7期1183-1200,共18页建筑模拟（英文）

基　　金：supported by the National Natural Science Foundation of China(No.42175095,No.42005069,and No.42175180);support from Guangdong Major Project of Basic and Applied Basic Research(2020B0301030004,2021B0301030007);the UK GCRF Rapid Response Grant on“Transmission of SARS-CoV-2 virus in crowded indoor environment”,and the Innovation Group Project of the Southern Marine Science and Engineering Guangdong Laboratory(Zhuhai)(No.311020001)are also gratefully acknowledged.

摘　　要：Opening windows in coach buses is a practical approach to improving natural ventilation and mitigating infection risk(IR).Due to human behavior and weather conditions,the intermittent window opening strategy(IWOS)is a more common practice than keeping windows constantly open.Despite its prevalence,there are no studies exploring IWOS specifically in vehicles.We employed indoor-outdoor coupled CFD simulations to assess the effects of various IWOS on pathogen-laden droplet(PLD)dispersion and IR in a coach bus that occurred a COVID-19 outbreak in Hunan,China.Results reveal that after ventilating through two skylights for 600–1800 s,opening front and rear windows(FW+RW)or FW with a wind catcher(FW+WCH)for just 40 s can reduce PLD concentration(Cave)to 5%of its initial level and the intake fraction of the infector’s neighbor(IFn)drops by 95%.Upon closing FW+RW or FW+WCH,Cave and IFn take over 580 s to return to the pre-opening level.Moreover,intermittent FW opening halves Cave and IFn within 7 min,but leads to rapid increases upon window closure.Therefore,opening FW+RW and FW+WCH intermittently have pronounced impacts on indoor PLD concentration and are applicable approaches to control respiratory disease transmission in vehicles.According to the inhaled viral dose,it is recommended to open windows when driving time is over 12 minutes to reduce infection risk.In scenarios like epidemiological surveys and risk assessments,where assessing passenger infection risk is vital,some behaviors of opening windows cannot be overlooked and necessitate extra attention.

关 键 词：infection risk computational fluid dynamics air change rate per hour natural ventilation wind catcher tracer gas dispersion 

分 类 号：TU834[建筑科学—供热、供燃气、通风及空调工程]