A Particle and Energy Balance Model of the Orificed Hollow Cathode

Domonkos, Matthew T.

doi:10.2514/6.2002-4240

Cited by 20 publications

(16 citation statements)

References 13 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…At 300 ns, a significant number of secondary electrons are present inside the discharge chamber. A high value of secondary electron number density, 1×10 18 #/m 3 is observed near the cathode location. The secondary electron number density decreases rapidly at locations away from cathode.…”

Section: B Particle Resultsmentioning

confidence: 88%

See 1 more Smart Citation

Computational Model Tracking Primary Electrons, Secondary Electrons and Ions in the Discharge Chamber of an Ion Engine

Mahalingam¹,

Menart²

2005

41st AIAA/ASME/SAE/ASEE Joint Propulsion Conference &Amp;amp; Exhibit

View full text Add to dashboard Cite

Section: B Particle Resultsmentioning

confidence: 88%

“…The plasma near the cathode surface is quasi-neutral (ref. 18). At the exit of the hollow cathode orifice both primary electrons and ions are present.…”

Section: B Particle Advancementioning

confidence: 99%

Computational Model Tracking Primary Electrons, Secondary Electrons and Ions in the Discharge Chamber of an Ion Engine

Mahalingam¹,

Menart²

2005

41st AIAA/ASME/SAE/ASEE Joint Propulsion Conference &Amp;amp; Exhibit

View full text Add to dashboard Cite

“…Under this assumption neutral density can be calculated as follows [30]: Under this assumption neutral density can be calculated as follows [30]:…”

Section: Orifice Modelmentioning

confidence: 99%

“…In order to calculate the neutral density in the orifice plasma, it is assumed that choked flow phenomenon occurs at the orifice exit. Under this assumption neutral density can be calculated as follows [30]:…”

Section: Orifice Modelmentioning

confidence: 99%

Global Numerical Model for the Assessment of the Effect of Geometry and Operation Conditions on Insert and Orifice Region Plasmas of a Thermionic Hollow Cathode Electron Source

Korkmaz

Çelik

2014

Contrib. Plasma Phys.

View full text Add to dashboard Cite

Thermionic hollow cathodes have been widely used in wide variety of areas such as spacecraft electric propulsion systems, material processing and lasers for more than half a century as efficient electron sources. Especially in electric propulsion systems, hollow cathodes are being used as electron sources for propellant ionization and ion beam neutralization. Moreover, it is also a promising candidate for utilization as a stand-alone propulsion system in microsatellites or nanosatellites due to its small physical size, low power consumption and ease of operation. On the other hand, the small geometry of the typical orificed hollow cathodes makes the plasma diagnostics difficult which is why numerical studies become important for understanding the driving physical processes behind their operation, and the effects of the geometry and the operation parameters on cathode performance. In this paper, a global numerical model for the insert and orifice plasma of a hollow cathode is presented where volume averaged plasma parameters are considered for both regions. The results of this study show that the developed model can be used for designing and sizing orificed hollow cathodes as comparisons with the results of experimental and other numerical studies are in good agreement with the ones obtained from the developed model.

show abstract

“…The estimation of the latter is beyond the scope of this paper. Calculation of the total pressure has been performed using an empirical relationship designed for a mercury hollow cathode, [9][10][11][12][13][14] an isentropic 15 or isothermal 16,17 flow approach, Poiseuille flow theory, 18-20 a modification of Poiseuille flow theory 21,22 (to take into account compressibility and molecular flow effects) and an "equivalent temperature" or modified specific gas constant taking into account the ionization fraction. 16,17,23,24 The empirical approach suggested by Siegfried and Wilbur [9][10][11][12][13] for mercury hollow cathodes and later extended by Friedly to xenon cathodes in Ref.…”

Section: Introductionmentioning

confidence: 99%

Correction: An empirical scaling relationship for the total pressure in hollow cathodes

Taunay

Wordingham

Choueiri

2018

2018 Joint Propulsion Conference

View full text Add to dashboard Cite

A non-dimensional scaling relationship for the total pressure inside thermionic, orificed hollow cathodes is derived empirically from a large database of experimental measurements and is analyzed statistically. The relationship allows calculating the total pressure inside hollow cathodes, which is necessary for self-consistent analytical models of the insert region and for insert lifetime calculations. The scaling relationship is a function of cathode operational parameters and is expressed as a non-dimensional power law. It is compared to experimental data for self-consistency and to theoretical modeling efforts. It is found that the empirical correlation agrees with experimental data with an R-squared value of 0.98 and average error of 24.5%, allows calculating the pressure over a range of three orders of magnitude or five orders of magnitude in the non-dimensional space, and is able to capture the dependency of the total pressure on the discharge current where theoretical models can not. For the dataset considered the scaling is shown to be insensitive to variations in the cathode orifice length, propellant ionization energy, and viscosity.

show abstract

A Particle and Energy Balance Model of the Orificed Hollow Cathode

Cited by 20 publications

References 13 publications

Computational Model Tracking Primary Electrons, Secondary Electrons and Ions in the Discharge Chamber of an Ion Engine

Computational Model Tracking Primary Electrons, Secondary Electrons and Ions in the Discharge Chamber of an Ion Engine

Global Numerical Model for the Assessment of the Effect of Geometry and Operation Conditions on Insert and Orifice Region Plasmas of a Thermionic Hollow Cathode Electron Source

Correction: An empirical scaling relationship for the total pressure in hollow cathodes

Contact Info

Product

Resources

About