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Resistive-wall-mode active rotation in the RFX-mod device.
T Bolzonella1, V Igochine, S C Guo
1Consorzio RFX, Associazione Euratom-ENEA sulla fusione, Padua, Italy. tommaso.bolzonella@igi.cnr.it
Physical Review Letters
|November 13, 2008
Summary
Plasma flow velocity
Area of Science:
- Plasma physics
- Fusion energy research
- Magnetohydrodynamics
Background:
- Understanding plasma flow's effect on magnetohydrodynamics (MHD) instabilities is crucial for fusion energy.
- Resistive-wall-mode instabilities in toroidal confinement devices are a key challenge.
Purpose of the Study:
- To investigate the influence of background plasma flow velocity on MHD instabilities.
- To demonstrate a novel method for controlling instability rotation in fusion devices.
Main Methods:
- Utilized a reversed field pinch experiment.
- Employed a set of active coils to control instability rotation.
- Compared experimental findings with numerical modeling.
Main Results:
- Achieved the first fully controlled rotation of a nonresonant instability in a reversed field pinch experiment.
- Demonstrated the impact of active coils on instability dynamics.
- Validated experimental results through numerical simulations.
Conclusions:
- Controlled plasma rotation is achievable and impacts instability behavior.
- The findings offer new insights into stabilizing plasma in fusion devices.
- This strategy advances the understanding and control of MHD instabilities.
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