Noise mitigation has been in the forefront of research and development since the advent of jet engines. Supersonic commercial and especially supersonic military aircraft cannot take the advantages offered by large bypass ratio engines due to significant drag penalty and performance degradation. Therefore, other control techniques must be utilized to reduce noise and satisfy the more recent and looming future stringent noise regulations. A class of plasma actuators has recently been developed at the Ohio State University that offers a significant promise. These actuators possess a wide bandwidth and can provide large amplitude perturbations enabling manipulation of various instabilities in high Reynolds number subsonic and supersonic jets for noise mitigation as well as mixing enhancement. A brief overview of the actuators and some results are presented in perfectly-expanded Mach 1.3 axisymmetric unheated and heated jets.
Mixing enhancement by tabs in round supersonic jets
