Proposed model of thermionically assisted breakdown and implementation on electrostatic thrusters
Bell, Walter J.
Olsen, R. C.
MetadataShow full item record
A model for thermionically assisted breakdown is proposed which predicts the voltage reduction experienced in low voltage discharges. This reduction in breakdown voltage has been beneficial to numerous engineering applications of arcs and is explored herein specifically for electrostatic thrusters. Full advantage in employing thermionically assisted breakdown is attained by establishing a continuum of electron emission across the primary discharge gap. These electrons must be independent of the discharge itself, being established prior to ignition. The electron emission is therefore achieved by auxiliary emitters across the gap. Electrons amass in a space charge in the vicinity of the assisting device. The particular processes which induce charge multiplication are proposed to be multistep ionization and neutralization of the space charge by ions. Breakdown criteria and a means of estimating the reduction is breakdown voltage requirement are derived. One proposal for the thermionically assisting emission device is the coiled-coil filament, and a scheme for installing such filaments in ionization chambers for electrostatic thrusters is described. Thermionically assisted breakdown implementation should also pertain to arc applications for various primary electrode geometries as well as certain gases.
Approved for public release; distribution is unlimited
Showing items related by title, author, creator and subject.
Callahan, Michael O. (Monterey, California. Naval Postgraduate School, 1993-12);Electrical breakdown in high voltage diodes has been studied since the 1920s, yet it is still not well understood. This study characterizes the electron flow during breakdown in a high voltage vacuum diode. This was ...
A study of the breakdown mechanism of AISI 304 stainless steel, type 2024 aluminum and various titanium coatings Beelby, Michael Howard; Ulrich, Henry George, III (Monterey, California. Naval Postgraduate School, 1981-12);An investigation, experimental and theoretical, into the breakdown mechanisms and associated minimum power levels required for the breakdown and unipolar arcing was conducted for AISI 304 stainless steel and Type 2024 ...
Kolbas, Patrick Joseph (Monterey, California. Naval Postgraduate School, 1991-06);This thesis examines the implications for nuclear deterrence between the United States and the Soviet Union brought about by the dramatic changes in the strategic environment during the 1980s. Specifically, it examines the ...