乘客在公車內打噴嚏之飛沫擴散分析

Analysis of droplet spreading caused by sneezing of passengers in buses

10.29911/JEHVACE_NEW.202303_(138).0001

羅彥然(Yan-Ran Luo)；蔡尤溪(Yew-Khoy Chuah)

飛沫擴散 ； 氣流模擬 ； 公車 ； 打噴嚏 ； Droplet spread ； Airflow simulation ； Bus ； Sneeze

冷凍空調&能源科技

138期（2023 / 03 / 10）

20 - 27

繁體中文;英文

近年來，全球接連爆發多起大規模呼吸道傳染疾病，如SARS-CoV以及MERS-CoV等，如今COVID-19也正在全球大流行。人體在呼吸、咳嗽、說話、打噴嚏和其他行為間產生之飛沫和氣溶膠顆粒為病毒顆粒的主要來源，感染者於密閉環境排放之傳染性氣溶膠顆粒可能在室內空氣中停留數小時，造成極大的感染風險。大眾運輸工具乘客密集處於密閉環境，若沒有適當之通風和戴口罩，將會成為一大潛在的病毒傳播媒介。本研究探討公車內感染者打噴嚏後，所造成之飛沫顆粒於公車內部之擴散與傳播，以CFD軟體建立公車內的3D模型，包括乘客在座位仿真方式進行電腦動態模擬。本研究也考量公車內部空調送風口不同出風方向和感染者位於不同位置時，排放之飛沫顆粒擴散行為的模擬。研究結果表明，排放飛沫顆粒乘客之前、後一排區域為可能造成氣溶膠傳播之高風險區域，車廂內部之圓形出風口建議之出風方向為垂直向下，對其他乘客造成之可能的感染風險最小。

In recent years, there have been a series of outbreaks of large-scale respiratory infectious diseases, such as SARS-CoV and MERS-CoV, around the world. Droplets and aerosol particles produced by the human during breathing, coughing, talking, sneezing and other actions are the main source of virus particles. Infectious aerosol particles emitted by an infected person in a closed environment may remain in the indoor air for several hours, which will increase the risk of infection. Passengers are crowded in a closed environment in public transportation, without proper ventilation and wearing masks, it will become a potential virus transmission vector. This study investigates the spread of droplet particles inside a bus caused by an infected person's sneeze. The 3D model of the bus is built with CFD software, including the computer dynamic simulation of the passengers on the seat. This study simulates the spread of droplet particles from a sneeze. The factors to be considered are the different directions of the air-conditioning in the bus and the different locations of the infected persons. The results of this study showed that the area between the front row and the back row of an infected person is a high-risk area that may cause aerosol transmission. The circular air inlet inside the bus is recommended to be directed vertically downward, which may cause the least possible infection risk to other passengers.

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