Previous studies reported that specially designed ventilation systems provide good air quality and safe environment by removing airborne droplets that contain viruses expelled by infected people.These water droplets c...Previous studies reported that specially designed ventilation systems provide good air quality and safe environment by removing airborne droplets that contain viruses expelled by infected people.These water droplets can be stable in the environment and remain suspended in air for prolonged periods.Encounters between droplets may occur and droplet interactions should be considered.However,the previous studies focused on other physical phenomena(air flow,drag force,evaporation)for droplet transport and neglected droplet interactions.In this work,we used computational fluid dynamics(CFD)to simulate the transport and fate of airborne droplets expelled by an asymptomatic person and considered droplet interactions.Droplet drag with turbulence for prediction of transport and fate of droplets indicated that the turbulence increased the transport of 1μm droplets,whereas it decreased the transport of 50μm droplets.In contrast to only considering drag and turbulence,consideration of droplet interactions tended to increase both the transport and fate.Although the length scale of the office is much larger than the droplet sizes,the droplet interactions,which occurred at the initial stages of release when droplet separation distances were shorter,had a significant effect in droplet fate by considerably manipulating the final locations on surfaces where droplets adhered.Therefore,it is proposed that when an exact prediction of transport and fate is required,especially for high droplet concentrations,the effects of droplet interactions should not be ignored.展开更多
基金supported by the Brain Pool Program through the National Research Foundation of Korea(NRF)funded by the Ministry of Science and ICT,Republic of Korea(No.2019H1D3A 2A02101993).
文摘Previous studies reported that specially designed ventilation systems provide good air quality and safe environment by removing airborne droplets that contain viruses expelled by infected people.These water droplets can be stable in the environment and remain suspended in air for prolonged periods.Encounters between droplets may occur and droplet interactions should be considered.However,the previous studies focused on other physical phenomena(air flow,drag force,evaporation)for droplet transport and neglected droplet interactions.In this work,we used computational fluid dynamics(CFD)to simulate the transport and fate of airborne droplets expelled by an asymptomatic person and considered droplet interactions.Droplet drag with turbulence for prediction of transport and fate of droplets indicated that the turbulence increased the transport of 1μm droplets,whereas it decreased the transport of 50μm droplets.In contrast to only considering drag and turbulence,consideration of droplet interactions tended to increase both the transport and fate.Although the length scale of the office is much larger than the droplet sizes,the droplet interactions,which occurred at the initial stages of release when droplet separation distances were shorter,had a significant effect in droplet fate by considerably manipulating the final locations on surfaces where droplets adhered.Therefore,it is proposed that when an exact prediction of transport and fate is required,especially for high droplet concentrations,the effects of droplet interactions should not be ignored.
