The emergence of the novel coronavirus has led to a global pandemic which has led to the airline industry facing severe losses. For air travel to recover, airlines need to ensure safe air travel. In this paper, the au...The emergence of the novel coronavirus has led to a global pandemic which has led to the airline industry facing severe losses. For air travel to recover, airlines need to ensure safe air travel. In this paper, the authors have modeled droplet dispersion after a single breath from an index patient. Computational Fluid Dynamics (CFD) simulations are conducted using the k-ωSST turbulence model in ANSYS Fluent. The authors have taken into consideration several parameters such as the size of the mouth opening, the velocity of the cabin air as well as the number of droplets being exhaled by the index patient to ensure a realistic simulation. Preliminary results indicate that after a duration of 20 s, droplets from the index patient disperse within a 10 m2 cabin area. About 75% of the droplets are found disperse for up to 2 m axially behind the index patient. This could possess an enhanced risk to passengers sitting behind the index patient. Ultimately, this paper provides an insight into the potential of CFD to visualise droplet dispersal and give impetus to ensure that necessary mitigating measures can be taken to reduce the risk of infection through droplet dispersal.展开更多
Objective To investigate the epidemiologic features of an outbreak of SARS that occurred in a single diabetes room of a general hospital in Beijing in late March 2003.Methods Field investigation was carried out in the...Objective To investigate the epidemiologic features of an outbreak of SARS that occurred in a single diabetes room of a general hospital in Beijing in late March 2003.Methods Field investigation was carried out in the ward,the nursing log and the hospitalization medical record of correlative patients were consulted.SARS-CoV in serum specimen from SARS patient was detected by PCR.Results The room where SARS outbreak occurred was on the 13th floor of the 16-story main ward building.There were 6 beds in the room,living with 6 female patients(aged 45-67)who were all hospitalized due to type2 diabetes.On March 24,2003,Patient 1 began to have a fever and cough,chest X-ray showed pneumonia.Five and six days later,Patient 2 and Patient 3 began to have a fever,respectively.Finally,all of these 3 patients died.Their beds were all at the same side of the room,and the other 3 patients at the opposite side were not infected.Serum SARS CoV-RNA of the Patient 3 was positive by nest-PCR.The daughter-in-law of Patient 1who accompanied Patient 1 by the bedside several days,mainly near the window,upwind of Patient 1,was not infected.Medical staff,family members and visitors of the 6 patients were not infected.Conclusions This outbreak was not transmitted by aerosol.The distance droplets travels could be up to 3.43 meters.Droplet spread has direction,and the droplets direction of propagation is closely related with the wind direction and speed.Those at the downwind position of SARS patients were susceptible to be infected.Medical staff wore face masks and good natural ventilation of this ward building may be important reasons for the prevention of infection.展开更多
文摘The emergence of the novel coronavirus has led to a global pandemic which has led to the airline industry facing severe losses. For air travel to recover, airlines need to ensure safe air travel. In this paper, the authors have modeled droplet dispersion after a single breath from an index patient. Computational Fluid Dynamics (CFD) simulations are conducted using the k-ωSST turbulence model in ANSYS Fluent. The authors have taken into consideration several parameters such as the size of the mouth opening, the velocity of the cabin air as well as the number of droplets being exhaled by the index patient to ensure a realistic simulation. Preliminary results indicate that after a duration of 20 s, droplets from the index patient disperse within a 10 m2 cabin area. About 75% of the droplets are found disperse for up to 2 m axially behind the index patient. This could possess an enhanced risk to passengers sitting behind the index patient. Ultimately, this paper provides an insight into the potential of CFD to visualise droplet dispersal and give impetus to ensure that necessary mitigating measures can be taken to reduce the risk of infection through droplet dispersal.
文摘Objective To investigate the epidemiologic features of an outbreak of SARS that occurred in a single diabetes room of a general hospital in Beijing in late March 2003.Methods Field investigation was carried out in the ward,the nursing log and the hospitalization medical record of correlative patients were consulted.SARS-CoV in serum specimen from SARS patient was detected by PCR.Results The room where SARS outbreak occurred was on the 13th floor of the 16-story main ward building.There were 6 beds in the room,living with 6 female patients(aged 45-67)who were all hospitalized due to type2 diabetes.On March 24,2003,Patient 1 began to have a fever and cough,chest X-ray showed pneumonia.Five and six days later,Patient 2 and Patient 3 began to have a fever,respectively.Finally,all of these 3 patients died.Their beds were all at the same side of the room,and the other 3 patients at the opposite side were not infected.Serum SARS CoV-RNA of the Patient 3 was positive by nest-PCR.The daughter-in-law of Patient 1who accompanied Patient 1 by the bedside several days,mainly near the window,upwind of Patient 1,was not infected.Medical staff,family members and visitors of the 6 patients were not infected.Conclusions This outbreak was not transmitted by aerosol.The distance droplets travels could be up to 3.43 meters.Droplet spread has direction,and the droplets direction of propagation is closely related with the wind direction and speed.Those at the downwind position of SARS patients were susceptible to be infected.Medical staff wore face masks and good natural ventilation of this ward building may be important reasons for the prevention of infection.
