Schlieren Photography of the Outflow From a Plasma Jet

Using Schlieren photography, the helium outflow configuration from a fine capillary-based microplasma jet discharge has been captured for free-stream conditions. The transition from laminar to turbulent flow is clearly identified with and without operation of the plasma. At a flow rate of 2.3 L·min^-1 with no plasma operating, this transition occurs 54 mm from the nozzle; however, with plasma struck (peak voltages of 8 kV_p-p), this reduces to 40 mm.