Understanding SARS-CoV-2 transmission: Computational fluid dynamics modelling of respiratory particles
This report from Theme 2 researchers on the PROTECT NCS, describes the development and use of a mathematical Computational Fluid Dynamics (CFD) model of respiratory droplet dispersion. The aim of the study was to help provide a better understanding of the physics of the transmission of the SARS-CoV-2 virus. As part of the model development, the researchers compared its predictions with experimental data. Their results demonstrated that the model is suitable for modelling real world scenarios.
The researchers’ findings include the following. Firstly, screens are an effective mitigation method to reduce dispersion for short durations and prevent large droplets from reaching the other side of the screen. However, screens are not effective over longer durations as small droplets are carried by the air around the screen. Secondly, medium-sized droplets may remain suspended for longer than expected due to evaporation and could therefore be important in determining exposure risk. Thirdly, measurements of carbon dioxide in the air are only partially effective as a proxy for exposure to SARS-CoV-2.