Numerical investigation of aerosol transport in a classroom with relevance to COVID-19

The present study investigates aerosol transport and surface deposition in a realistic classroom environment using computational fluid-particle dynamics simulations. Effects of particle size, aerosol source location, glass barriers, and windows are explored. While aerosol transport in air exhibits some stochasticity, it is found that a significant fraction (24%-50%) of particles smaller than 15 mu m exit the system within 15 min through the air conditioning system. Particles larger than 20 mu m almost entirely deposit on the ground, desks, and nearby surfaces in the room. Source location strongly influences the trajectory and deposition distribution of the exhaled aerosol particles and affects the effectiveness of mitigation measures such as glass barriers. Glass barriers are found to reduce the aerosol transmission of 1 mu m particles from the source individual to others separated by at least 2.4 m by similar to 92%. By opening windows, the particle exit fraction can be increased by similar to 38% compared to the case with closed windows and reduces aerosol deposition on people in the room. On average, similar to 69% of 1 mu m particles exit the system when the windows are open.