Aerosol Spread in a Generic Train Entrance: Comparison Between Experiment and Numerical Simulation

The global COVID-19 outbreak in 2020 has made understanding pathogen-laden aerosol transport and the associated transmission routes more relevant than ever. To determine how aerosol particles generated by continuous breathing accumulate in confined spaces, the particle concentrations in a small room resembling a train entrance are investigated. The room is ventilated and equipped with two heated manikins, one of which is continuously exhaling aerosol through the mouth for 30 min. For this setup we conducted local particle measurements in the center plane and a RANS simulation including the prediction of the transient particle transport. It is shown that the particle concentration increases logarithmically and attains a nearly steady state. The resulting local particle concentrations normalized to the source concentrations are subsequently compared. We find good agreement with the experiment in the exhalation zone of the breathing manikin and larger differences for the sensor positions beneath the ventilation inlet.