Abstract View
On the Intricate Relationship between Ventilation, Deposition and Airborne Virus Transmission in Indoor Environments
K. MAX ZHANG, Bo Yang, Khaled Hashad, Alfredo Rodriguez, Cornell University
Abstract Number: 590
Working Group: Infectious Aerosols in the Age of COVID-19
Abstract
We have developed a detailed computational fluid dynamics (CFD)-based aerosol dynamics model and conducted extensive model evaluations against experimental datasets that characterized indoor turbulence, evaporation and deposition. Applying this model in realistic indoor environments in hospitals and schools enabled us to elucidate the intricate relationship between ventilation, deposition and droplet/aerosol transmission. Higher ventilation rate leads to shorter particle resident time and higher surface deposition, but also results in longer particle travel distance. Capturing surface deposition is critical to quantify particle number balance, even though fomite transmission may not be important. Our results support the argument that 5-micron size cut between aerosol and droplets is arbitrary and we showed the more reasonable size cut to be between 85 and 115 microns, which is consistent with the proposed 100 microns size cut. For examples, droplets of initial size of 80 microns can travel much further than 6 feet under realistic indoor environments.