Temperature Measurements in Alternating Current Cross-Flow Arcs

Using optical techniques appropriate to columns having non-circular cross-section, temperature distributions within an alternating current cross-flow arc column have been obtained. Experiments were conducted upon a 61.1 A rms, 840 Torr argon AC plasma (having 11.2 mm electrode spacing) in a crossflow of 1.1 m/s. Isotherm distributions, obtained in horizontal planes, were generally non-circular with major axis in the direction of flow. Column deflections increased as arc current was reduced. The (characteristic) temperature-time history showed that temperature reached a minimum following current zero.