Numerical study of air movement in a slot-ventilated enclosure

In this paper, airflow in a slot-ventilated enclosure is numerically studied at Reynolds number 5024, which is based on inlet height and mean velocity at the inlet. Both Reynolds averaged Navier-Stokes (RANS) simulation and large eddy simulation (LES) are applied, and numerical results are compared to corresponding experimental data. Most of the flow features observed in experiments could be predicted by both RANS and LES models, but the latter provides more detailed flow structures. Mean velocity from both numerical simulations agrees fairly well with the measurements. It is found that LES does not show much superiority over the RANS model for predicting mean velocity. Investigation of subgrid constant and viscosity ratio shows that the instantaneous airflow is a combination of turbulence and laminar and transitional flows. The paper also analyzes the vortex dynamics in the flow with recourse to flow feature extraction techniques. Vortex cores are extracted and their roles in the evolution of flow are analyzed.