Effects of Plasma Shaping on Nonlinear Gyrokinetic Turbulence
Abstract
The effects of flux surface shape on the gyrokinetic stability and transport of tokamak plasmas are studied using the GS2 code [M. Kotschenreuther, G. Rewoldt, and W.M. Tang, Comput. Phys. Commun. 88, 128 (1995); W. Dorland, F. Jenko, M. Kotschenreuther, and B.N. Rogers, Phys. Rev. Lett. 85, 5579 (2000)]. Studies of the scaling of nonlinear turbulence with shaping parameters are performed using analytic equilibria based on interpolations of representative shapes of the Joint European Torus (JET) [P.H. Rebut and B.E. Keen, Fusion Technol. 11, 13 (1987)]. High shaping is found to be a stabilizing influence on both the linear iontemperaturegradient (ITG) instability and the nonlinear ITG turbulence. For the parameter regime studied here, a scaling of the heat flux with elongation of χ ~ κ ^{1.5} or κ ^{2.0}, depending on the triangularity, is observed at fixed average temperature gradient. While this is not as strong as empirical elongation scalings, it is also found that high shaping results in a larger Dimits upshift of the nonlinear critical temperature gradient due to an enhancement of the RosenbluthHinton residual zonal flows.
 Authors:
 Princeton Plasma Physics Lab. (PPPL), Princeton, NJ (United States)
 Univ. of Maryland, College Park, MD (United States)
 Publication Date:
 Research Org.:
 Princeton Plasma Physics Lab. (PPPL), Princeton, NJ (United States)
 Sponsoring Org.:
 USDOE Office of Science (SC)
 OSTI Identifier:
 939431
 Report Number(s):
 PPPL4342
TRN: US0806853
 DOE Contract Number:
 AC0276CHO3073
 Resource Type:
 Technical Report
 Country of Publication:
 United States
 Language:
 English
 Subject:
 70 PLASMA PHYSICS AND FUSION TECHNOLOGY; CRITICAL TEMPERATURE; ELONGATION; HEAT FLUX; INSTABILITY; MAGNETIC SURFACES; PLASMA; SHAPE; STABILITY; TEMPERATURE GRADIENTS; TRANSPORT; TURBULENCE; Tokamaks
Citation Formats
E. A. Belli, Hammett, G. W., and Dorland, W. Effects of Plasma Shaping on Nonlinear Gyrokinetic Turbulence. United States: N. p., 2008.
Web. doi:10.2172/939431.
E. A. Belli, Hammett, G. W., & Dorland, W. Effects of Plasma Shaping on Nonlinear Gyrokinetic Turbulence. United States. doi:10.2172/939431.
E. A. Belli, Hammett, G. W., and Dorland, W. Fri .
"Effects of Plasma Shaping on Nonlinear Gyrokinetic Turbulence". United States.
doi:10.2172/939431. https://www.osti.gov/servlets/purl/939431.
@article{osti_939431,
title = {Effects of Plasma Shaping on Nonlinear Gyrokinetic Turbulence},
author = {E. A. Belli and Hammett, G. W. and Dorland, W.},
abstractNote = {The effects of flux surface shape on the gyrokinetic stability and transport of tokamak plasmas are studied using the GS2 code [M. Kotschenreuther, G. Rewoldt, and W.M. Tang, Comput. Phys. Commun. 88, 128 (1995); W. Dorland, F. Jenko, M. Kotschenreuther, and B.N. Rogers, Phys. Rev. Lett. 85, 5579 (2000)]. Studies of the scaling of nonlinear turbulence with shaping parameters are performed using analytic equilibria based on interpolations of representative shapes of the Joint European Torus (JET) [P.H. Rebut and B.E. Keen, Fusion Technol. 11, 13 (1987)]. High shaping is found to be a stabilizing influence on both the linear iontemperaturegradient (ITG) instability and the nonlinear ITG turbulence. For the parameter regime studied here, a scaling of the heat flux with elongation of χ ~ κ1.5 or κ2.0, depending on the triangularity, is observed at fixed average temperature gradient. While this is not as strong as empirical elongation scalings, it is also found that high shaping results in a larger Dimits upshift of the nonlinear critical temperature gradient due to an enhancement of the RosenbluthHinton residual zonal flows.},
doi = {10.2172/939431},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Fri Aug 01 00:00:00 EDT 2008},
month = {Fri Aug 01 00:00:00 EDT 2008}
}

The effects of flux surface shape on the gyrokinetic stability and transport of tokamak plasmas are studied using the GS2 code [M. Kotschenreuther, G. Rewoldt, and W. M. Tang, Comput. Phys. Commun. 88, 128 (1995); W. Dorland, F. Jenko, M. Kotschenreuther, and B. N. Rogers, Phys. Rev. Lett. 85, 5579 (2000)]. Studies of the scaling of nonlinear turbulence with shaping parameters are performed using analytic equilibria based on interpolations of representative shapes of the Joint European Torus [P. H. Rebut and B. E. Keen, Fusion Technol. 11, 13 (1987)]. High shaping is found to be a stabilizing influence on bothmore »

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