A Preliminary Study in Regularizing the Coherent Structures in a Planar, Weakly-Compressible, Free Shear Layer

This paper presents our first attempt at regularizing the coherent, vortical structures in a planar, relatively-high-Mach-number free shear layer. The purpose of regularizing the structures is to reduce the bandwidth required by an adaptive optic system to correct for the aero-optic aberrations imposed on a laser beam passing through the shear layer. In order to regularize the structures, plasma actuators were used. Analysis is given that suggests that the plasma actuators are best suited for this regularization. Results are presented for a single actuator design operated in two modes using four ac waveforms. This configuration showed mixed but somewhat encouraging results.

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