A numerical study of the saturation process inside a rectangular open cavity is presented. Previous experiments and linear stability analysis of the problem completely described the flow in a saturated regime, characterized by three-dimensional centrifugal modes. The morphology of the modes found in the experiments matched the ones predicted by linear analysis, but with a shift in frequencies for the oscillating modes. A three-dimensional Direct Numerical Simulation (DNS) is employed for a detailed investigation of the saturation process inside a cavity with dimensions similar to the ones used in the experiments. Periodic boundary conditions are imposed to better understand the effect of saturation far from the walls. The main flow structures are identified using the Dynamic Mode Decomposition (DMD) technique, and compared to previous experimental and linear stability analysis results. A preliminary DNS study taking into account spanwise solid wall boundary conditions, and reproducing the full dynamics of the experiments, is also presented.
展开▼
