High-Speed and High-Reynolds-Number Jet Control Using Localized Arc Filament Plasma Actuators

A class of plasma actuators called localized arc filament plasma actuators for high-speed and high-Reynolds-number flow and acoustic control has been developed at the Gas Dynamics and Turbulence Laboratory. Over the past several years, these high-bandwidth (0 to 200 kHz) and individually controlled actuators have been used successfully to excite the jet shear layer, jet column, and azimuthal instabilities in high subsonic and supersonic jets. The focus of this paper is to provide detailed information and sample results highlighting the capabilities and potential of the actuators and the control technique for mixing enhancement, noise mitigation, and flow and acoustic diagnostics. The jet, using three different nozzles, is operated over a large range of Jet Mach numbers (0.9 to 1.65), stagnation temperature ratios (up to 2.5), and Reynolds numbers (0.2 x 10(6) to 1.65 x 10(6)). Over this space of operating conditions, the jet is found to respond to control with a large range of forcing Strouhal numbers and azimuthal modes. The results reveal that the jet flowfield and acoustic far field can be dramatically altered, providing a powerful control tool in these practical high-speed and high-Reynolds-number jets.