タイトル | Preliminary Development and Testing of a Self-Injecting Gallium MPD Thruster |
本文(外部サイト) | http://hdl.handle.net/2060/20080048103 |
著者(英) | Thomas, Robert E.; Polzin, Kurt A.; Burton, Rodney L. |
著者所属(英) | NASA Marshall Space Flight Center |
発行日 | 2008-07-20 |
言語 | eng |
内容記述 | Discharge current and terminal voltage measurements were performed on a gallium electromagnetic thruster at discharge currents in the range of 20-54 kA. It was found that the arc impedance has a value of 6-7 m(Omega) at peak current. The absence of high-frequency oscillations in the terminal voltage trace indicates lack of the "onset" condition often seen in MPD arcs, suggesting that a sufficient number of charge carriers are present for current conduction. The mass ablated per pulse was not measured experimentally; however the mass flow rate was calculated using an ion current assumption and an anode power balance. Measurement of arc impedance predicts a temperature of 3.5 eV which from Saha equilibrium corresponds to Z = 2.0 - 3.5, and assuming Z = 2 yields an Isp of 3000 s and thrust efficiency of 50%. |
NASA分類 | Spacecraft Propulsion and Power |
権利 | Copyright, Distribution as joint owner in the copyright |