How air moves when we speak or breathe

In Howard Stone’s lab, researchers are examining the flows when people breathe and speak to better understand the spread of COVID-19; the flows transport aerosol particles. In this video, Nan Xue, a graduate student in the lab, demonstrates an experiment that simulates someone speaking or breathing by controlling the pressure and flow rate to send jets or puffs of air into the room. The team uses smoke to track the flow of the air, and a laser to see it, recording the speeds and distances traveled of the flow in an enclosed environment. “We want to visualize this flow, and quantify how far it can go,” Xue said. The team compares these measurements with similar studies of flows created by a person breathing and speaking. The research is also being performed by Manouk Abkarian, Simon Mendez and Fan Yang, and is being funded by the National Science Foundation (NSF) Rapid Response Research program.