Advanced turbulence models for predicting particle transport in enclosed environments

Occupant health is related to particle contaminants in enclosed environments, so it is important to study particle transport in spaces to quantify the rates and routes of potential disease transmission. In many cases, particle contaminants in an enclosed space are generated from an unsteady source. This investigation used the experimental data from two steady-state cases as well as one transient particle dispersion case in evaluating the performance of five (one steady and four transient) airflow models with the Eulerian and Lagrangian methods. The transient models obtained the mean flow and particle information by averaging them over time. For the models tested in this study, the Eulerian method performed similarly for all five airflow models. The Lagrangian method predicted incorrect particle concentrations with the Reynolds-Averaged Navier–Stokes (RANS) and Unsteady Reynolds-Averaged Navier–Stokes (URANS) methods, but did well with the Large Eddy Simulation (LES) and Detached Eddy Simulation (DES) models. For unsteady-state particle dispersion, the LES or DES models, along with the Lagrangian method, showed the best performance among all the models tested.