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Wear Testing of the HERMeS ThrusterThe Hall-Effect Rocket with Magnetic Shielding (HERMeS) thruster is being developed and tested at NASA GRC and NASA JPL through support of the Space Technology Mission Directorate (STMD) as primary propulsion for the Asteroid Redirect Robotic Mission (ARRM). This thruster is advancing the state-of-the-art of Hall-effect thrusters and is intended to serve as a precursor to higher power systems for human interplanetary exploration. A 2000-hour wear test has been initiated at NASA GRC with the HERMeS Technology Demonstration Unit One and three of four test segments have been completed totaling 728 h of operation. This is the first test of a NASA-designed magnetically shielded thruster to extend beyond 300 hr of continuous operation. Trends in performance, component wear, thermal design, plume properties, and back-sputtered deposition are discussed for two wear-test segments of 246 h and 360 h. The first incorporated graphite pole covers in an electrical configuration where cathode was electrically connected to thruster body. The second utilized traditional alumina pole covers with the thruster body floating. It was shown that the magnetic shielding in both configurations completely eliminated erosion of the boron nitride discharge channel but resulted in erosion of the inner pole cover. The volumetric erosion rate of the graphite pole covers was roughly 2/3 that of the alumina pole covers and the thruster exhibited slightly better performance. Buildup of back-sputtered carbon on the BN channel at a rate of roughly 1.5 μm/kh is shown to have negligible impact on the performance.
Document ID
Document Type
Conference Paper
Williams, George J., Jr.
(Ohio Aerospace Inst. Brook Park, OH, United States)
Gilland, James H.
(Ohio Aerospace Inst. Brook Park, OH, United States)
Peterson, Peter Y.
(Vantage Partners, LLC Cleveland, OH, United States)
Kamhawi, Hani
(NASA Glenn Research Center Cleveland, OH United States)
Huang, Wensheng
(NASA Glenn Research Center Cleveland, OH United States)
Ahern, Drew M.
(NASA Glenn Research Center Cleveland, OH United States)
Yim, John
(NASA Glenn Research Center Cleveland, OH United States)
Herman, Daniel A.
(NASA Glenn Research Center Cleveland, OH United States)
Hofer, Richard R.
(Jet Propulsion Lab., California Inst. of Tech. Pasadena, CA, United States)
Sekerak, Michael
(Alcyon Technical Services. Pasadena, CA, United States)
Date Acquired
January 31, 2017
Publication Date
July 25, 2016
Subject Category
Spacecraft Propulsion And Power
Report/Patent Number
Meeting Information
AIAA/SAE/ASEE Joint Propulsion Conference(Salt Lake City, UT)
Funding Number(s)
WBS: WBS 729200.06.03.05
Distribution Limits
Public Use Permitted.
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