Self-sustained Oscillation for a Three Dimensional Transonic Cavity Using LES

The effect of sidewall in self-sustained oscillation of an open cavity has been analyzed to understand the flow instability and influence of acoustic waves for transonic flow using Large-Eddy Simulation (LES). The present simulation resolves the formation of shear layer, its rollup resulting in large-scale structures apart from shock-shear layer interactions and evolution of acoustic waves. Presence of sidewall generates streamwise vortices that grow and convect downstream, while interacting with the spanwise rollup of shear layer. This results in coherent structures that finally impinge on the aft wall generating acoustics.