Dispersion of expectorated cough droplets with seasonal influenza in an office

Abstract

We do not fully grasp viral droplet transmission processes in ventilated interior environments. The core focus of our research is to investigate the effectiveness of the protected occupied zone ventilation (POV) through computational fluid dynamics models in a simplified office setting. The large-eddy simulation technique with the Eulerian–Lagrangian model was implemented to address complicated indoor processes such as turbulence, flow–aerosol interaction, and ventilation impact. We computationally investigated the effects of desk partitions and the POV on cough droplets in an office. The ventilation approach was tested using two distinct exhaust layouts and four different ventilation rates (1.0, 1.2, 1.5, and 1.8 m/s). A comparative analysis of the ventilation flow fields, topologies, and particle directions has been studied. The findings indicate that the plane jet's ventilation rates influence the protected occupied zone ventilation performance. The ventilation rates distributed the virus droplets around the room, but compared to the up-exhaust cases, the down-exhaust cases appeared to have better shielded the healthy person. This pattern could indicate that the placement of the exhaust outlet in ventilation systems significantly influences indoor aerosol dispersion. The results also show that substantial flow streams may carry tiny particles (≤70 μm) throughout their path. Large particles (≥100 μm) could not go far in cough gas clouds. Most viral particles deposit on solid surfaces in various work sites per specific ventilation rates. Office workers need to be very cautious around these hazardous areas.