Stabilization of ballooning modes with sheared toroidal rotation

Journal Article · Sun Oct 01 04:00:00 EDT 1995 · Physics of Plasmas

DOI:https://doi.org/10.1063/1.871067· OSTI ID:118427

Miller, R L; Waelbroeck, F L; Hassam, A B; Waltz, R E ^[1]

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1. General Atomics, San Diego, California 92186-9784 (United States)

Stabilization of magnetohydrodynamic ballooning modes by sheared toroidal rotation is demonstrated using a shifted circle equilibrium model. A generalized ballooning mode representation is used to eliminate the fast Alfven wave, and an initial value code solves the resulting equations. The {ital s}{minus}{alpha} diagram (magnetic shear versus pressure gradient) of ballooning mode theory is extended to include rotational shear. In the ballooning representation, the modes shift periodically along the field line to the next point of unfavorable curvature. The shift frequency ({ital d}{Omega}/{ital dq}, where {Omega} is the angular toroidal velocity and {ital q} is the safety factor) is proportional to the rotation shear and inversely proportional to the magnetic shear. Stability improves with increasing shift frequency and direct stable access to the second stability regime occurs when this frequency is approximately one-quarter to one-half the Alfven frequency, {omega}{sub A}={ital V}{sub A}/{ital qR}. {copyright} {ital 1995} {ital American} {ital Institute} {ital of} {ital Physics}.

• DOE Contract Number: FG03-92ER54150; FG05-80ET53088
• OSTI ID: 118427
• Journal Information: Physics of Plasmas, Journal Name: Physics of Plasmas Journal Issue: 10 Vol. 2; ISSN PHPAEN; ISSN 1070-664X
• Country of Publication: United States
• Language: English

Related Subjects

70 PLASMA PHYSICS AND FUSION TECHNOLOGY
ALFVEN WAVES
BALLOONING INSTABILITY
EIKONAL APPROXIMATION
MHD EQUILIBRIUM
NUMERICAL SOLUTION
ROTATING PLASMA
SHEAR PROPERTIES
STABILIZATION
TOKAMAK DEVICES