Particle Transport Predictions in a Generic Room: Comparison of URANS and RANS with Experiments

Kurzfassung

The SARS-CoV-2 pandemic highlighted the need to understand aerosol transport and associated disease transmission and motivated many numerical flow studies using different numerical approaches for the prediction of Lagrangian particle transport for infection risk modeling with different levels of accuracy and computational costs. To evaluate the trade-off between these different flow simulation approaches, we compare particle concentration predictions based on the solutions of steady and unsteady Reynolds-averaged Navier-Stokes (RANS) equations with experimental data. A generic train entrance region is selected since it is an easy setup for experiments and numerical flow simulations. Two heated manikins are placed in this ventilated room, one of them exhaling aerosol. The RANS approach predicts significant particle accumulations that are neither observed in the experiments nor in the URANS simulations. However, the averaged absolute deviation from the experimental data decreases by a factor of 2.4 if URANS simulations are performed, albeit at an eight-fold increase in computational cost.