Bluff body flow control with atmospheric plasma actuators

Description/Abstract

Plasma actuators operating in atmospheric air were employed to modify aerodynamic flow over a bluff body. The model consisted of a cylinder and a strut that was installed on the trailing half side of the cylinder. The objective was to reduce the broadband noise that is mainly generated by the impingment of the cylinder wake on the strut. The plasma actuators were configured to produce dielectric barrier discharges, through which the flow separation from the cylinder was enhanced. As a result the wake-strut interaction was reduced, leading to the attenuation of broadband noise. The noise and flow control performance with the plasma actuators were studied in an anechoic chamber facility as well as a wind tunnel facility by examining sound pressure and mean flow field respectively. With the current plasma actuators, it was found that there was 1 dB reduction in overall sound pressure level at a freestream speed of 30 m/s, and the wake speed impinging on the strut was reduced. A possible solution to improve the broadband noise attenuation performance is discussed in the end of this paper.