ELECTRON-HEAVY PARTICLE NONEQUILIBRIUM IN A DENSE ARGON PLASMA.
Abstract
A theoretical and experimental study of the degree of electron heavy particle thermal nonequilibrium was conducted for a subsonic argon arcjet plasma at one atmosphere. A criterion for 'electron-temperature freezing' was calculated, and indicated that although electron and heavy-particle temperatures were quite close to each other under typical arcjet environments, measurable departures should be observed at the lower temperature or density conditions. These analytical findings were verified quantitatively by simultaneous experimental measurements of the local electron temperature and heavy-particle temperature in the arcjet. These measurements were made with a unique water-cooled calorimetric-electrostatic probe. Proper interpretations of the electrostatic probe data in a dense plasma (argon at 1 atm) was verified by three accurate independent measurements (calorimetric, log current vs voltage, and saturation current ratio). It was also concluded that under certain (typical) conditions, the cooled electrostatic probe could provide a good approximation to the electron density in a dense plasma, and could provide an indication of plasma flow turbulence. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Jul 01, 1966
- Accession Number
- AD0646891
Entities
People
- Jerry Grey
- Paul F. Jacobs
Organizations
- Princeton University