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Updated: May 25, 2026
06:42
Magnetically Induced Rotating Rayleigh-Taylor Instability
Published on: March 3, 2017
Stabilization of the resistive wall mode by a rotating solid conductor
C Paz-Soldan1, M I Brookhart, A T Eckhart
1Physics Department, University of Wisconsin-Madison, Madison, Wisconsin 53706, USA.
Physical Review Letters
|January 17, 2012
Summary
High-speed rotating walls stabilize plasma instabilities like the resistive wall mode (RWM). This research demonstrates that faster wall rotation increases plasma current limits, expanding the stable operating window for fusion energy devices.
Area of Science:
- Plasma physics
- Fusion energy research
- Magnetohydrodynamics
Background:
- Resistive wall modes (RWMs) are plasma instabilities that can limit fusion device performance.
- Stabilizing RWMs is crucial for achieving sustained fusion reactions.
- Error fields can disrupt intrinsic plasma rotation, leading to RWM locking and growth.
Purpose of the Study:
- To demonstrate the stabilization of RWMs using high-speed differentially rotating conducting walls.
- To investigate the effect of wall rotation on RWM behavior and plasma stability.
- To determine if rotating walls can expand the operational window for RWM-stable plasma currents.
Main Methods:
- Experimental demonstration of RWM stabilization in a laboratory setting.
- Controlled braking of intrinsic plasma rotation using error fields.
- Observation and analysis of RWM frequency, amplitude, and growth rate under varying wall rotation speeds and alignments.
Main Results:
- High-speed rotating walls effectively reduce the saturated amplitude and growth rate of locked RWMs.
- RWM onset occurs at higher plasma currents with increased wall rotation speeds.
- Static or slowly rotating walls result in locked RWMs, with behavior dependent on wall-plasma alignment.
Conclusions:
- Differential rotation of conducting walls is a viable method for RWM stabilization.
- Increased wall rotation broadens the RWM-stable operating regime, enabling higher plasma currents.
- This technique offers a pathway to improved plasma confinement and performance in fusion devices.
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