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Indexed by:期刊论文

Date of Publication:2012-01-01

Journal:PLASMA SCIENCE & TECHNOLOGY

Included Journals:SCIE、EI、Scopus

Volume:14

Issue:1

Page Number:14-19

ISSN No.:1009-0630

Key Words:equilibrium current profile; MHD instability; bootstrap current; tokamak

Abstract:A cylindrical model of linear MHD instabilities in tokamaks is presented. In the model, the cylindrical plasma is surrounded by a vacuum which is divided into inner and outer vacuum areas by a conducting wall. Linearized resistivity MHD equations with plasma viscosity are adopted to describe our model, and the equations are solved numerically as an initial value problem. Some of the results are used as benchmark tests for the code, and then a series of equilibrium current profiles are used to simulate the bootstrap current profiles in actual experiments with a bump on tail. Thus the effects of these kinds of profiles on MHD instabilities in tokamaks are revealed. From the analysis of the numerical results, it is found that more plasma can be confined when the center of the current bump is closer to the plasma surface, and a higher and narrower current bump has a better stabilizing effect on the MHD instabilities.