Dynamic Measurements of Arc Temperature Distribution, Radius, and Current in a Pulsed Coaxial Plasma

Spectroscopic techniques, in synchronization with a high-speed rotating mirror arrangement, have been employed to determine the dynamic response characteristics of a well-stabilized coaxial arc plasma subjected to a step pulse in voltage; data acquisition time is about 5 μs. Experiments were conducted in argon at 1.1 atmospheres pressure with mass flows of 0.107, 0.157, and 0.206 grams per second. Radial distributions of temperature were obtained at various times during the transient. The timewise variation of arc radius was also determined.