Hollow cathode life-time prediction from low work function surface coverage evolution
Hollow cathode life-time prediction from low work function surface coverage evolution
In this paper a procedure to update the plasma parameters relatively to changes of the hollow cathode surface work function has been developed. This procedure has been validated with experimental results and then coupled with the deposition/desorption model already developed by the authors. The evolution of the surface of the cathode tested for 28,000 hours by Sarver-Verhey has been simulated and from the data obtained an end of life criterion has been developed. Then using this criterion the ELT NSTAR discharge cathode has been simulated for various throttle conditions deriving the lifetime at TH0 (200,000 h), TH8 (100,000 h) and TH15 (25,000 h). The lifetimes found are in agreement with the theoretical expectation. The lifetime of the ELT NSTAR cathode under the throttling conditions used during the Deep Space 1 Spare Ion Engine life test has been found to be in excess of 30,000 hours and in particular 100,000 or more if the cathode is run at TH8 or lower from 30,000 hours onward.
hollow, cathode, life, time, work, function
Coletti, M.
f99567c2-8fab-42dd-9e25-c3f69495667f
Gabriel, S.B.
ac76976d-74fd-40a0-808d-c9f68a38f259
22 July 2008
Coletti, M.
f99567c2-8fab-42dd-9e25-c3f69495667f
Gabriel, S.B.
ac76976d-74fd-40a0-808d-c9f68a38f259
Coletti, M. and Gabriel, S.B.
(2008)
Hollow cathode life-time prediction from low work function surface coverage evolution.
44th AIAA/ASME/SAE/ASEE Joint Propulsion Conference & Exhibit, Hartford, United States.
21 - 23 Jul 2008.
Record type:
Conference or Workshop Item
(Paper)
Abstract
In this paper a procedure to update the plasma parameters relatively to changes of the hollow cathode surface work function has been developed. This procedure has been validated with experimental results and then coupled with the deposition/desorption model already developed by the authors. The evolution of the surface of the cathode tested for 28,000 hours by Sarver-Verhey has been simulated and from the data obtained an end of life criterion has been developed. Then using this criterion the ELT NSTAR discharge cathode has been simulated for various throttle conditions deriving the lifetime at TH0 (200,000 h), TH8 (100,000 h) and TH15 (25,000 h). The lifetimes found are in agreement with the theoretical expectation. The lifetime of the ELT NSTAR cathode under the throttling conditions used during the Deep Space 1 Spare Ion Engine life test has been found to be in excess of 30,000 hours and in particular 100,000 or more if the cathode is run at TH8 or lower from 30,000 hours onward.
Text
depositionplasmaJPC2008new.pdf
- Other
More information
Published date: 22 July 2008
Venue - Dates:
44th AIAA/ASME/SAE/ASEE Joint Propulsion Conference & Exhibit, Hartford, United States, 2008-07-21 - 2008-07-23
Keywords:
hollow, cathode, life, time, work, function
Organisations:
Astronautics Group
Identifiers
Local EPrints ID: 64435
URI: http://eprints.soton.ac.uk/id/eprint/64435
PURE UUID: a74752ff-fe61-4bdf-9759-fb86406518b9
Catalogue record
Date deposited: 07 Jan 2009
Last modified: 15 Mar 2024 11:49
Export record
Contributors
Author:
M. Coletti
Author:
S.B. Gabriel
Download statistics
Downloads from ePrints over the past year. Other digital versions may also be available to download e.g. from the publisher's website.
View more statistics