Local Negative Shear and the Formation of Transport Barriers

Journal Article · Mon Jul 01 00:00:00 EDT 1996 · Physical Review Letters

DOI:https://doi.org/10.1103/PhysRevLett.77.494· OSTI ID:286742

Drake, J F; Lau, Y T; Guzdar, P N; Hassam, A B; Novakovski, S V; Rogers, B; Zeiler, A ^[1]

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1. Institute for Plasma Research, University of Maryland, College Park, Maryland 20742 (United States)

We present a set of 3D nonlinear equations describing drift-resistive ballooning modes in a torus including the self-consistent modification of the local magnetic shear due to the finite {beta} shift of the flux surfaces. Simulations using these equations reveal that a bifurcation of the transport occurs when the local magnetic shear on the outside midplane reverses sign. A fully self-consistent bifurcation diagram is calculated which reveals significant hysteresis, i.e., the transport barrier is maintained at lower values of {beta} than is required for the formation of the barrier, as expected from the experimental observations. {copyright} {ital 1996 The American Physical Society.}

• OSTI ID: 286742
• Journal Information: Physical Review Letters, Vol. 77, Issue 3; Other Information: PBD: Jul 1996
• Country of Publication: United States
• Language: English

Related Subjects

70 PLASMA PHYSICS AND FUSION
PLASMA
SHEAR
BALLOONING INSTABILITY
PLASMA DRIFT
TRANSPORT
NONLINEAR PROBLEMS
THREE-DIMENSIONAL CALCULATIONS
MODIFICATIONS
BIFURCATION
TOROIDAL CONFIGURATION
PRESSURE GRADIENTS
FLUX TUBES