CFD based air flow and contamination modeling of subway stations

We describe the addition of train dynamics, thermal sources and street level air coupling to Computational Fluid Dynamic based modeling of air flow in subway tunnels and stations. These new features provide more realistic simulations that are validated against experimental data in an initial proof-of-concept. Numerical simulations are then carried out in more complex subway station geometries. The air flow dynamics in these stations are quantified in terms of their spatial complexity and temporal stability using vortex core lines and proper orthogonal decomposition. These values are useful in correlating adjustable parameters such as train schedules to the dispersion and transport of pollutants though the stations. Simulations and air flow analyzes are performed for a real subway station in Dortmund, Germany for future comparison against experimental measurements of air flow, temperature and concentrations of inter gas released within the station.