Accession Number : ADA506820


Title :   A Study of Ignition Effects on Thruster Performance of a Multi-Electrode Capillary Discharge Using Visible Emission Spectroscopy Diagnostics


Descriptive Note : Technical paper


Corporate Author : AIR FORCE RESEARCH LAB EDWARDS AFB CA PROPULSION DIRECTORATE


Personal Author(s) : Pancotti, Anthony P


Full Text : https://apps.dtic.mil/dtic/tr/fulltext/u2/a506820.pdf


Report Date : 01 Sep 2009


Pagination or Media Count : 162


Abstract : This work examined the effect of ignition on thruster performance characteristics of a capillary discharge device. Early tests of the presented device, incorporating an exploding wire ignition, showed a strong dependence on the initial plasma conditions. The literature supported these findings for more basic laboratory capillaries, but the effect on a thruster device was unknown. An indepth investigation of different ignition systems were conducted for a capillary discharge based pulsed plasma thruster. In addition to conventional wires, capillary discharges were ignited with low pressure gas and several different types of spark igniters. These methods were compared with each other and with newly developed computer models. The viability of a capillary discharge based electro thermal pulsed plasma thruster as an in-space propulsion system was examined. Thruster performance levels, and their ability to fill a desired niche, which has historically shown rather poor efficiencies, have been explored. This work contains a background literature study, experimental setup and testing of a capillary design, and a comparison to performance models created by others. New techniques have been coupled with proven plasma diagnostics to investigate the internal plasma properties of the device. Visible-light spectroscopy techniques were developed to examine the time-resolved electron number densities at the exit. Novel thrust stand techniques were demonstrated, measuring thruster performance characteristics with a high degree of accuracy.


Descriptors :   *CAPILLARY TUBES , *THRUSTERS , *EMISSION SPECTROSCOPY , *IGNITION , *ELECTRIC DISCHARGES , LASER DIAGNOSTICS , ELECTRODES , COMPARISON , ELECTRON DENSITY , COMPUTERIZED SIMULATION , VISIBLE SPECTRA


Subject Categories : Electricity and Magnetism
      Atomic and Molecular Physics and Spectroscopy
      Combustion and Ignition
      Electric and Ion Propulsion


Distribution Statement : APPROVED FOR PUBLIC RELEASE