Mechanisms of Magnetoplasmadynamic Arcjet Acceleration Processes.
Abstract
Investigations into methods of utilizing ambient gas as propellant at satellite altitudes have been experimentally and analytically investigated. As part of this investigation, a class of space charge limited plasma accelerators has been studied. Experimentally, discharges in these devices are low current (.1 amp to 2 amps) and high voltage (200v to 10,000v). Ions are produced by electron bombardment of the adsorbed gases on the anode. Treating the flow of ions and electrons as a conducting fluid permits analogies with fluid flow phenomena. Sub- and supercritical flow for both ions and electrons correspond to subsonic and supersonic flow in a fluid. In one-dimensional flow, the electric field creates an electrostatic nozzle with critical flow occurring where the electric field is zero (the electrostatic throat) a rigorous analysis of the flow gives qualitative agreement with measured discharge characteristics. Space charge buildup limits the ratio of beam power to electric power input to under 1% for the operating mode wherein ions are produced from the adsorbed gas on the anode. Conventional performance as a pulsed plasma accelerator can be obtained by desorbing the gas from the anode rapidly so that breakdown occurs. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Dec 01, 1978
- Accession Number
- ADA065617
Entities
People
- Adriano C. Ducati
- Gordon L. Cann