Aerosol dispersion of state-of-art ventilation concepts in passenger trains - a comparative study

Kurzfassung

We report on an experimental study regarding the performance of state-of-the-art ventilation systems with different inlet positions with respect to the aerosol spread. For that, the spatial distribution of aerosol exposure was determined for six different source locations in a generic passenger compartment. This allowed us to evaluate the different concepts in terms of parameters such as contaminant removal efficiency, the number of seats above a certain threshold or the mean particle concentration in the breathing zone of the passengers. The results revealed strong differences in the local particle concentrations depending on the source position. Further, it was found that two ceiling-based concepts, microjet ceiling and ceiling mounted slot diffusers aimed at the passengers, have significant advantages over the other concepts, especially when it comes to the number of seats with aerosol exposures above certain thresholds. Yet, which concept is optimal still depends on the chosen threshold. The contaminant removal efficiency fluctuates only weakly around 0.5 for the different concepts, revealing mixing-ventilation principles for all concepts.