Past work has shown that adjoint-based optimization can identify perturbations that make unsteady free shear flows substantially quieter. These perturbations are interesting because they offer the opportunity to study noise mechanisms and because they themselves constitute successful noise-reducing controls. Here we apply these techniques to an experimentally validated simulation of a Mach 1.3 pressure-matched turbulent jet. The noise is successfully suppressed. Changes in both the turbulence and acoustic fields are analyzed, including with a proper orthogonal decomposition. The principal effect of the control is the suppression of particularly loud intermittent events. Despite the significant reduction, only small changes in the jet structure are observed.
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