TECHNICAL PHYSICS LETTERS, cilt.48, sa.4, ss.1-4, 2022 (SCI-Expanded)
Recently several investigators reported on various devices of generating cold plasma jets at atmospheric pressure. A pulsed plasma source developed and reported, “the plasma pencil”, is one of them. This device is capable of generating a cold plasma plume several centimeters in length using a DC pulsed high voltage source. In this study, kHz alternative current voltage (18 kV-15 kHz) was applied to the electrodes similar to the electrode system of the plasma pencil instead of direct current pulse voltage and a 2-3 cm long plasma jet was produced in an air using the helium gas. This new plasma jet device named as the “kHz plasma pencil”. The jets produced by the kHz plasma pencil are as cold as room temperature. The optical emission spectrum of the jet of the kHz plasma pencil and the change of the jet length with the gas flow rate have been investigated. Unlike the plasma pencil, the kHz plasma pencil produces jet in two different regimes as filamentary and diffusive and it emits more radiation in the UV range. Preliminary results show that the dynamics of the kHz plasma pencil are also different from the plasma pencil.