Title :
Laser Imaging and Velocimetry of Cathode-Spot-Ejected Ceramic Powder
Author :
Gillman, Eric D. ; Foster, John E.
Author_Institution :
Dept. of Nucl. Eng. & Radiol. Sci., Univ. of Michigan, Ann Arbor, MI, USA
Abstract :
Velocimetry of ceramic particles ejected via cathode spot eruption on the surface of a biased electrode in the presence of a low-density plasma has been carried out. Witness plate measurements indicated the rate of powder removal to be greater than 3.0 mg/s. An expanded laser beam and fast frame-rate camera were used to perform laser-illuminated particle imaging velocimetry measurements. The velocity distribution for 45- μm-diameter ceramic particles was found to range between 0.2 and 1.5 m/s in the plane of view as they are ejected from the electrode surface. Nonuniform powder ejection in the horizontal plane is shown to be related to the presence of an applied magnetic field.
Keywords :
arcs (electric); ceramics; dusty plasmas; laser beam effects; laser velocimeters; plasma diagnostics; powders; velocity measurement; applied magnetic field; arc discharges; biased electrode; cathode-spot-ejected ceramic powder; dusty plasma; expanded laser beam; frame-rate camera; glow discharges; laser-illuminated particle imaging; low-density plasma; plate measurements; powder removal rate; size 45 mum; velocimetry; velocity distribution; Cathodes; Ceramics; Magnetic resonance imaging; Plasmas; Powders; Surface treatment; Arc discharges; dusty plasma; glow discharges; laser velocimetry; particle tracking; radio communication;
Journal_Title :
Plasma Science, IEEE Transactions on
DOI :
10.1109/TPS.2011.2162253
