The effect of air supply rate on indoor infection probability in mixing ventilation

Abstract

SARS-Cov-2 has caused enormous damage to society and put human health at a hazardous level. Optimizing air distribution patterns is one of the most useful manners to minimize the infection risk of susceptible individuals. Mixing ventilation is widely used, but the effect of air supply rate on indoor infection probability has not been studied yet. Three air supply rates, including 576, 864 and 1152 m3/h were adopted to study this problem in a simulated room, with dimensions of 5m×5m×2.7m. The Computational Fluid Dynamics (CFD) method was used to consider indoor flow fields under three cases. The infection probability was calculated by the revised Wells-Riley model. The results showed that the overall infection probability decreased as the air supply rate increased. Meanwhile, the infectious air exhaled by the infector would flow along with the supply airflow in a certain direction, resulting in a nonuniform distribution of infection probability in the room. Increasing air supply rate and optimizing workstation layout may be two useful manners to reduce infection probability in mixing ventilation rooms.