[Table of Contents]

Plasma and Fusion Research

Volume 1, 015 (2006)

Rapid Communications

A Shear-Flow Instability Relevant to Advanced Tokamak Operation
Tomoya TATSUNO and William DORLAND
Center for Scientific Computation and Mathematical Modeling, The University of Maryland
(Received 1 February 2006 / Accepted 17 February 2006 / Published 27 March 2006)

Abstract

An ideal magnetohydrodynamic instability which is driven by sheared flow and which may be relevant to reversed-shear advanced tokamak operation is described. If there is flow shear at the qmin surface, relatively weak velocity shear can drive this instability, with a time scale of the flow. The flows may be signicantly slower than the ambient poloidal Alfvén velocity, and no inflection point is needed. Thus the time scale of the instability may be signicantly longer than that of the poloidal Alfvén transit time, and it might account for disruption of reversed-shear discharges recently observed in JT-60U.

Keywords

MHD, shear flow, instability, reversed-shear tokamak, disruption

DOI: 10.1585/pfr.1.015

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This paper may be cited as follows:

Tomoya TATSUNO and William DORLAND, Plasma Fusion Res. 1, 015 (2006).