Plasma candle: A new type of scaled−up plasma jet device

This paper presents a new type of plasma jet device that incorporates porous ceramic plate perpendicular to the helium gas flow. This new configuration enables a plasma jet with a nozzle diameter larger of 10 mm – 31 mm, which has not previously been reported for a plasma jet. We call this large-diameter plasma jet a plasma candle. The advantage of this new device is that a treating area can be extended up to 100 ~ 754 mm2. The pore size of the ceramic was found to be important to form a stable plasma candle. The optimum pore size was found to be approximately10 μm. The imaging of the plasma jet revealed that charge build-up on the downstream of the porous ceramic plate and its growth toward the nozzle outlet is an important aspect in the scale up of plasma jet.