Drift-kinetic simulation of neoclassical transport with impurities in tokamaks

Journal Article · Mon Feb 15 04:00:00 EST 2010 · Physics of Plasmas

DOI:https://doi.org/10.1063/1.3310839· OSTI ID:21347122

Kolesnikov, R A ^[1]; Wang, W X; Rewoldt, G; Tang, W M ^[2]; Hinton, F L ^[3]

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1. Los Alamos National Laboratory, Los Alamos, New Mexico 87544 (United States)
2. Plasma Physics Laboratory, Princeton, New Jersey 08543 (United States)
3. University of California, San Diego, La Jolla, California 92093 (United States)

Plasmas in modern tokamak experiments contain a significant fraction of impurity ions in addition to the main deuterium background ions. A new multiple ion-species deltaf particle simulation capability has been developed to self-consistently study the nonlocal effects of impurities on neoclassical transport in toroidal plasmas. A new algorithm for an unlike-particle collision operator, including test-particle and conserving field-particle parts, is described. Effects of the carbon impurity on the main deuterium species heat flux as well as an ambipolar radial electric field in a National Spherical Torus Experiment (NSTX) [M. Ono, S. M. Kaye, Y.-K. M. Peng et al., Nucl. Fusion 40, 557 (2000)] configuration were studied. A difference between carbon poloidal rotation found from simulation and from conventional theoretical estimates has been investigated and was identified to be a nonlocal finite orbit effect. In the case of large-aspect ratio tokamak configurations with steep toroidal flow profiles, we propose a theoretical model to describe this nonlocal effect. The dominant mechanisms captured by the model are associated with ion parallel velocity modification due to steep toroidal flow and radial electric field profiles. We present simulation results for carbon poloidal velocity in NSTX. Comparisons with neoclassical theory are discussed.

• OSTI ID: 21347122
• Journal Information: Physics of Plasmas, Journal Name: Physics of Plasmas Journal Issue: 2 Vol. 17; ISSN PHPAEN; ISSN 1070-664X
• Country of Publication: United States
• Language: English

Related Subjects

70 PLASMA PHYSICS AND FUSION TECHNOLOGY
ALGORITHMS
CARBON
CHARGED PARTICLES
CHARGED-PARTICLE TRANSPORT THEORY
CLOSED PLASMA DEVICES
DEUTERIUM
ELEMENTS
HYDROGEN ISOTOPES
IMPURITIES
IONS
ISOTOPES
LIGHT NUCLEI
MATHEMATICAL LOGIC
NEOCLASSICAL TRANSPORT THEORY
NONMETALS
NSTX DEVICE
NUCLEI
ODD-ODD NUCLEI
PLASMA IMPURITIES
PLASMA SIMULATION
SIMULATION
SPHEROMAK DEVICES
STABLE ISOTOPES
THERMONUCLEAR DEVICES
TOKAMAK DEVICES
TRANSPORT THEORY