Distribution of droplet aerosols generated by mouth coughing and nose breathing in an air-conditioned room

The objective of this study is to understand the distribution of droplet aerosols in an air-conditioned room, which is very important to comprehend how infectious bacteria and viruses transmit from person to person through respiratory activities. To predict droplet aerosols distribution in this paper, adopted Large Eddy Simulation (LES) CFD model coupling with Lagrangian method is established and validated through the experiment in a climate chamber. Mouth coughing and nose breathing with changing airflow velocities are investigated in the simulation to study the influence of supply air temperature and relative humidity, ventilation rate and ventilation pattern on the number of suspended, deposited and escaped droplet aerosols. The results show that compared with ventilation rate and air distribution patterns, supply air temperature and relative humidity have less influence on the number of suspected and escaped droplets aerosols with displacement ventilation (DV). Compared with Mixing ventilation (MV), DV has significant effect on reduction of the human exposure. These findings and the adopted simulation method may be used to study the effects of different ventilation systems on distributing droplets aerosols in various indoor spaces, such as buildings and public transports.