In flow over cavity-backed openings, instability in the shear flow can result in self-excited oscillations of the flow. These can become coupled to a resonant response of the cavity, resulting in high amplitude pressure fluctuations in the cavity. Recent studies have shown that these self-excited oscillations can persist even in the presence of a perforated plate or a series of regularly spaced slats in the opening. In this study, various flow-field quantities of a self-excited cavity flow at different speeds and with and without regularly spaced slats in the opening are examined and compared. Unstructured hybrid RANS/LES methods are used to simulate shear driven cavity flows with and without slats at a resonant-coupled speed, as well as without slats at a lower, nonresonant-coupled speed. The results are compared to experimental data for corresponding conditions to validate the numerical results. Various flow field quantites, including the energy production term and the energy flow vector, are calculated from the data and compared for the different conditions in order to understand the features of the flow associated with self-excited oscillations with slats in the opening.

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