Accession Number : AD0714540

Title :   Ion Current to a Pherical Probe in a Flowing High Pressure Plasma under Thin-Sheath Conditions,

Corporate Author : VICTORIA UNIV (BRITISH COLUMBIA) DEPT OF PHYSICS

Personal Author(s) : Clements,M. ; Smy,P. R. ; Eng,C.

Report Date : 05 MAY 1970

Pagination or Media Count : 4

Abstract : The current to a large (radius = 2.4mm) negatively biased spherical probe in a flowing plasma (a propane/air flame) has been measured over wide ranges of plasma-ionisation density (3 x 10 to the power (15 to 18)/cubic m), probe bias (10-400V) and probe/plasma relative velocity (3-40m/s). Under these conditions, the sheath surrounding the probe is thin and the probe current is a function of the probe/plasma velocity. In consequence, the static continuum probe theory of Su and Lam, and the motionally dependent thick-sheath theory of Clements and Smy are both found to be in error by at least an order of magnitude. A thin-sheath relationship has been derived for the spherical probe which shows excellent agreement with the experimental data. (Author)

Descriptors :   (*PLASMA MEDIUM, LANGMUIR PROBES), ELECTRON DENSITY, PLASMA SHEATHS, IONIZATION, HYDRODYNAMICS, CANADA

Subject Categories : Plasma Physics and Magnetohydrodynamics

Distribution Statement : APPROVED FOR PUBLIC RELEASE