A horizontal powder injector for W7-X
Abstract
We report that injection of low-Z powders into fusion plasma has been used to improve wall conditions, similar to the standard boronization process using diborane. Powder injection has the advantage of being much simpler, non-toxic, and efficient. The W7-X stellarator is planning on utilizing powder injection in long pulse discharges; a proof-of-principle test for horizontal injection into the plasma was conceived, a Probe Mounted Particle Injector (PMPI). The PMPI concept is developed using a polyetheretherketone (PEEK) paddle wheel hub that is driven by a piezo motor, due to the high magnetic fields, that rotates at 100 deg/s. This small PMPI fits into an envelope of 120 mm diameter × 150 mm long, a standard size for Multi-Purpose Manipulator (MPM). The device is housed in a carbon cup mounted on a retractable probe that can be placed near the plasma edge, enabling powder injection ˜4–8 cm radially into the boundary plasma. The feed for the paddle is via piezo electric actuator that vibrates a funnel filled with powder into a trough for the paddle to push. The 8 paddle arms, 35 mm long and 10 mm wide, are made from 0.38 mm thick PEEK which drag slightly along the powder-filled troughmore »
- Authors:
-
[1];
- Princeton Plasma Physics Lab. (PPPL), Princeton, NJ (United States)
- Max-Planck-Institut für Plasmaphysik, Teilinstitut Greifswald (Germany)
- Publication Date:
- Research Org.:
- Princeton Plasma Physics Lab. (PPPL), Princeton, NJ (United States)
- Sponsoring Org.:
- USDOE
- OSTI Identifier:
- 1493874
- Alternate Identifier(s):
- OSTI ID: 1562546
- Grant/Contract Number:
- AC02-09CH11466
- Resource Type:
- Accepted Manuscript
- Journal Name:
- Fusion Engineering and Design
- Additional Journal Information:
- Journal Volume: 146; Journal ID: ISSN 0920-3796
- Publisher:
- Elsevier
- Country of Publication:
- United States
- Language:
- English
- Subject:
- 70 PLASMA PHYSICS AND FUSION TECHNOLOGY; 36 MATERIALS SCIENCE; Impurity; Powder; Injection; Horizontal; Piezo feeder; Boronization
Citation Formats
Nagy, Alexander, Bortolon, A., Gates, D., Gilson, E., Killer, C., Klinger, T., Lunsford, R., Maingi, R., Mansfield, D., Mauzey, D., Nazikian, R., Roquemore, L., and Wolfe, E. A horizontal powder injector for W7-X. United States: N. p., 2019.
Web. doi:10.1016/j.fusengdes.2018.12.099.
Nagy, Alexander, Bortolon, A., Gates, D., Gilson, E., Killer, C., Klinger, T., Lunsford, R., Maingi, R., Mansfield, D., Mauzey, D., Nazikian, R., Roquemore, L., & Wolfe, E. A horizontal powder injector for W7-X. United States. https://doi.org/10.1016/j.fusengdes.2018.12.099
Nagy, Alexander, Bortolon, A., Gates, D., Gilson, E., Killer, C., Klinger, T., Lunsford, R., Maingi, R., Mansfield, D., Mauzey, D., Nazikian, R., Roquemore, L., and Wolfe, E. Sat .
"A horizontal powder injector for W7-X". United States. https://doi.org/10.1016/j.fusengdes.2018.12.099. https://www.osti.gov/servlets/purl/1493874.
@article{osti_1493874,
title = {A horizontal powder injector for W7-X},
author = {Nagy, Alexander and Bortolon, A. and Gates, D. and Gilson, E. and Killer, C. and Klinger, T. and Lunsford, R. and Maingi, R. and Mansfield, D. and Mauzey, D. and Nazikian, R. and Roquemore, L. and Wolfe, E.},
abstractNote = {We report that injection of low-Z powders into fusion plasma has been used to improve wall conditions, similar to the standard boronization process using diborane. Powder injection has the advantage of being much simpler, non-toxic, and efficient. The W7-X stellarator is planning on utilizing powder injection in long pulse discharges; a proof-of-principle test for horizontal injection into the plasma was conceived, a Probe Mounted Particle Injector (PMPI). The PMPI concept is developed using a polyetheretherketone (PEEK) paddle wheel hub that is driven by a piezo motor, due to the high magnetic fields, that rotates at 100 deg/s. This small PMPI fits into an envelope of 120 mm diameter × 150 mm long, a standard size for Multi-Purpose Manipulator (MPM). The device is housed in a carbon cup mounted on a retractable probe that can be placed near the plasma edge, enabling powder injection ˜4–8 cm radially into the boundary plasma. The feed for the paddle is via piezo electric actuator that vibrates a funnel filled with powder into a trough for the paddle to push. The 8 paddle arms, 35 mm long and 10 mm wide, are made from 0.38 mm thick PEEK which drag slightly along the powder-filled trough bottom, becoming a spring-loaded paddle which accelerates the powder upon release. Finally, design challenges are the high ambient magnetic field, vacuum compatible materials, high temperature environment, limited rotary-drive options, and compact space. The design and testing of this new device will be presented.},
doi = {10.1016/j.fusengdes.2018.12.099},
journal = {Fusion Engineering and Design},
number = ,
volume = 146,
place = {United States},
year = {Sat Jan 26 00:00:00 EST 2019},
month = {Sat Jan 26 00:00:00 EST 2019}
}
Search WorldCat to find libraries that may hold this journalWeb of Science
Works referenced in this record:
A multi-species powder dropper for magnetic fusion applications
journal, October 2018
- Nagy, A.; Bortolon, A.; Mauzey, D. M.
- Review of Scientific Instruments, Vol. 89, Issue 10
A multi-purpose manipulator system for W7-X as user facility for plasma edge investigation
journal, November 2017
- Nicolai, D.; Borsuk, V.; Drews, P.
- Fusion Engineering and Design, Vol. 123
Works referencing / citing this record:
Charge exchange recombination spectroscopy at Wendelstein 7-X
journal, February 2020
- Ford, O. P.; Vanó, L.; Alonso, J. A.
- Review of Scientific Instruments, Vol. 91, Issue 2