Swirl Characterization of a Cyclotronic Arc Plasma Actuated Axial Air Jet

A plasma swirler, based on an existing Lorentz force driven gliding arcs, was developed as a flame holding and combustion enhancing device for premixed and diffusion flames. The device is intended to deliver the combined benefits of jet swirlers and plasma assisted combustion by providing fluidic mixing to augment flame stability, and high energy particles to enhance the combustion process. The current study focused on characterizing the fluid dynamic effects of the plasma swirler on an axial air jet ejected at various air flow rates in quiescent air. Schlieren imaging was used to study the thermal effects of the plasma on the axial air jet and qualitatively compare the turbulence levels in the actuated and unactuated jets. Time-averaged stereoscopic particle image velocimetry data were acquired across seven evenly-spaced planes perpendicular to the exit plane of the plasma swirler at three different axial flow rates, while maintaining constant plasma swirling parameters. These data were used to reconstruct three-component volumetric averaged velocity fields. Two-dimensional cross sections along with three-dimensional isosurfaces of the mean flow were used to describe the induced flow and flow turbulence levels, and characterize the vorticity created by the swirler.