Details

Autor(en) / Beteiligte

• Morgan, W. L.
• Rosocha, L. A.

Titel

The Physics and Plasma Chemistry of an RF Needle in a Saltwater Aerosol

Ist Teil von

• IEEE transactions on plasma science, 2012-12, Vol.40 (12), p.3174-3184

Ort / Verlag

New York: IEEE

Erscheinungsjahr

2012

Quelle

IEL

Beschreibungen/Notizen

• Experiments involving the insertion of a tungsten needle powered by an ~1-kW radio-frequency (RF) generator into a flowing saltwater mist produced by a nebulizer are described. The tip of the tungsten electrode is estimated to have a temperature near the 5555-°C vaporization temperature of tungsten. Values of E/N close to the electrode tip are estimated to be greater than the breakdown threshold of humid air. This arrangement of RF-powered electrode and flowing saltwater aerosol produces a flame of some 30 cm high having strong light emission near the 589-nm sodium-D lines. We present a model demonstrating that the emission trapped in the core along the length of the flame arises primarily from Na(3 2 P → 3 2 S) with some Na 2 * emission. The rising flame cools slowly due to a combination of the opacity of the hot gas, the large heat capacity of the H 2 O molecules in the flame, and the exothermicity of the plasma chemistry in the afterglow.