(TH/P3-14) Plasma Rotation Braking and Driving in Tokamaks

Linjin Zheng1), M. T. Kotschenreuther1), J. W. Van Dam1), F. L. Waelbroeck1), M. S. Chu2)
1) Institute for Fusion Studies, Univ. of Texas at Austin, Austin, Texas 78712, United States of America
2) General Atomics, P.O. Box 85608, San Diego, California 92186, United States of America

Abstract.  The current work addresses certain issues related to plasma rotation in tokamaks.We derive an explicit expression for the error-field-induced torque and determine the torque in ITER for a given error field strength in the case of shear Alfvén resonance using the AEGIS code. We find that the liquid metal wall can shield the error field effect by eliminating the resonant amplification and reversing self-enhancing synergistic sequence in the rotation braking. We also give an alternative theoretical explanation for the spontaneous rotation observed during the cyclotron wave heatings. Our theory agrees with experimental observations for various characteristic features: such as the co-current rotation direction for ion cyclotron radio-frequency heating, the counter-current rotation direction for electron cyclotron heating, and the scale of rotation as the plasma stored energy normalized by the plasma current.

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