Overview of NSTX Upgrade Initial Results and Modelling Highlights

Dataset · Sun Jan 01 00:00:00 EST 2017

DOI:https://doi.org/10.11578/1367890· OSTI ID:1367890

Menard, J.E.  ^[1]; Allain, J.P.; Battaglia, D.J.  ^[1]; Bedoya, F.; Bell, R.E.  ^[1]; Belova, E.  ^[1]; Berkery, J.W. ^[2]; Boyer, M.D.  ^[1]; Crocker, N.; Diallo, A.  ^[1]; Ebrahimi, F.  ^[1]; Ferraro, N.  ^[1]; Fredrickson, E. ^[1]; Frerichs, H.; Gerhardt, S.  ^[1]; Gorelenkov, N.  ^[1]; Guttenfelder, W.  ^[1]; Heidbrink, W.; Kaita, R.  ^[1]; Kaye, S.M. ^[1] ; Kriete, D.M.; Kubota, S.; LeBlanc, B.P.  ^[1]; Liu, D.  ^[1]; Lunsford, R.  ^[1]; Mueller, D.  ^[1]; Myers, C.E.; Ono, M. ^[1]; Park, J-K.  ^[1]; Podesta, M.  ^[1]; Raman, R.  ^[1]; Reinke, M.; Ren, Y.  ^[1]; Sabbagh, S.A.; Schmitz, O.; Scotti, F. ^[3]; Sechrest, Y.; Skinner, C.H. ^[1]; Smith, D.R. ^[4]; Soukhanovskii, V.; Stoltzfus-Dueck, T.  ^[1]; Yuh, H.; Wang, Z.  ^[1]; Waters, I.; Ahn, J-W.; Andre, R.; Barchfield, R.; Beiersdorfer, P.; Bertelli, N.  ^[1]; Bhattacharjee, A.  ^[1]; Boyle, D.  ^[1]; Brennan, D.; Buttery, R.; Capece, A.  ^[1]; Canal, G.; Canik, J.; Chang, C.S.  ^[1]; Darrow, D. ^[1]; Delgado-Aparicio, L.  ^[1]; Domier, C.; Ethier, S. ^[1]; Evans, T.; Ferron, J.; Finkenthal, M.; Fonck, R.; Gan, K.; Gates, D.  ^[1]; Goumiri, I. ^[4]; Gray, T.; Hosea, J.  ^[1]; Humphreys, D.; Jarboe, T.; Jardin, S.  ^[1]; Jaworski, M.A. ^[1]; Koel, B.  ^[5]; Kolemen, E.  ^[1]; Ku, S.  ^[1]; LaHaye, R.J.; Levinton, F.; Luhmann Jr., N.; Maingi, R.  ^[1]; Maqueda, R. ^[6]; McKee, G.; Meier, E.; Myra, J.; Perkins, R.  ^[1]; Poli, F.  ^[1]; Rhodes, T.; Riquezes, J.; Rowley, C.  ^[1]; Russell, D.; Schuster, E.; Stratton, B.  ^[1]; Stutman, D.; Taylor, G.  ^[1]; Tritz, K. ^[7]; Wang, W. ^[1]; Wirth, B.; Zweben, S.J.  ^[1]

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1. Princeton Plasma Physics Lab. (PPPL), Princeton, NJ (United States)
2. Columbia University, New York, NY, United States of America
3. Lawrence Livermore National Laboratory, Livermore, CA, United States of America
4. University of Wisconsin, Madison, WI, United States of America
5. Princeton Univ., NJ (United States). Dept. of Chemical Engineering
6. X Science LLC, Plainsboro, NJ, United States of America
7. Johns Hopkins University, Baltimore, MD, United States of America

The National Spherical Torus Experiment (NSTX) has undergone a major upgrade, and the NSTX Upgrade (NSTX-U) Project was completed in the summer of 2015. NSTX-U first plasma was subsequently achieved, diagnostic and control systems have been commissioned, H-Mode accessed, magnetic error fields identified and mitigated, and the first physics research campaign carried out. During 10 run weeks of operation, NSTX-U surpassed NSTX-record pulse-durations and toroidal fields, and high-performance ~1MA H-mode plasmas comparable to the best of NSTX have been sustained near and slightly above the n=1 no-wall stability limit and with H-mode confinement multiplier H98y2 above 1. Transport and turbulence studies in L-mode plasmas have identified the coexistence of at least two ion-gyro-scale turbulent micro-instabilities near the same radial location but propagating in opposite (i.e. ion and electron diamagnetic) directions. These modes have the characteristics of ion-temperature gradient and micro-tearing modes, respectively, and the role of these modes in contributing to thermal transport is under active investigation. The new second more tangential neutral beam injection was observed to significantly modify the stability of two types of Alfven Eigenmodes. Improvements in offline disruption forecasting were made in the areas of identification of rotating MHD modes and other macroscopic instabilities using the Disruption Event Characterization and Forecasting (DECAF) code. Lastly, the Materials Analysis and Particle Probe (MAPP) was utilized on NSTX-U for the first time and enabled assessments of the correlation between boronized wall conditions and plasma performance. These and other highlights from the first run campaign of NSTX-U are described.

• Research Organization: Princeton Plasma Physics Lab. (PPPL), Princeton, NJ (United States)
• Sponsoring Organization: USDOE Office of Science (SC), Fusion Energy Sciences (FES)
• DOE Contract Number: AC02-09CH11466
• OSTI ID: 1367890
• Resource Relation: Related Information: Nuclear Fusion, vol. 57, 102006 (June 2017)
• Country of Publication: United States
• Language: English

Related Subjects

70 PLASMA PHYSICS AND FUSION TECHNOLOGY
NSTX-U
Spherical tokamak
Alfven Eigenmodes