Investigation into Airborne Transport Characteristics of Airflow Due to Coughing in a Stagnant Indoor Environment

In this paper, the airborne transport characteristics of airflow due to coughing are investigated in a stagnant indoor environment using transient computational fluid dynamics (CFD) analysis on the dispersion of coughed airflow. The dispersion phenomena of the airflows generated by coughing
and exhaling were reproduced based on the unsteady models of coughing and breathing. The concentration simulation was coupled to simulate the dispersion of the coughed air. The simulation results indicate that in a stagnant environment :
(1) the indoor flow field is mainly determined by the air current from the air conditioner, the rising thermal stream due to the occupants metabolic heat, and the expelled airflows of the occupants; (2) although the coughed airflow initially travels at a high speed unaffected by the indoor airflow, it soon dissipates as its velocity drops sharply; and (3) it is possible for coughed air and aerosols to be inhaled by other occupants.