【摘 要】
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The Coronavirus Disease 2019(COVID-19)highlights the importance of understanding and controlling the spread of the coronavirus between persons.We experimentally and numer-ically investigated an advanced engineering and environmental method on controlling
【机 构】
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College of Civil Engineering,Hunan University,Changsha 410082,China;Key Laboratory of Building Safet
论文部分内容阅读
The Coronavirus Disease 2019(COVID-19)highlights the importance of understanding and controlling the spread of the coronavirus between persons.We experimentally and numer-ically investigated an advanced engineering and environmental method on controlling the transmission of airborne SARS-CoV-2-laden aerosols in the breathing microenvironment between two persons during interactive breathing process by combining the limited space air stability and a ventilation method.Experiments were carried out in a full-scale venti-lated room with different limited space air stability conditions,i.e.,stable condition,neutral condition and unstable condition.Two real humans were involved to conducted normal breathing process in the room and the exhaled carbon dioxide was used as the surrogate of infectious airborne SARS-CoV-2-laden aerosols from respiratory activities.A correspondent numerical model was established to visualize the temperature field and contaminated field in the test room.Results show that the performance of a ventilation system on removing infectious airborne SARS-CoV-2-laden aerosols from the interpersonal breathing microenvi-ronment is dependent on the limited space air stability conditions.Appropriate ventilation method should be implemented based on an evaluation of the air condition.It is recom-mended that total volume ventilation methods are suitable for unstable and neutral condi-tions and local ventilation methods are preferable for stable conditions.This study provides an insight into the transmission of airborne SARS-CoV-2-laden aerosols between persons in ventilated rooms with different limited space air stability conditions.Useful guidance has been provided to cope with COVID-19 in limited spaces.
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