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Updated: Jun 5, 2026
06:42
Magnetically Induced Rotating Rayleigh-Taylor Instability
Published on: March 3, 2017
The rotating wall machine: a device to study ideal and resistive magnetohydrodynamic stability under variable
C Paz-Soldan1, W F Bergerson, M I Brookhart
1Department of Physics, University of Wisconsin, 1150 University Ave, Madison, Wisconsin 53706, USA.
The Review of Scientific Instruments
|January 5, 2011
Summary
A new rotating wall machine investigates plasma instabilities by controlling electromagnetic boundary conditions. This facility allows precise manipulation of plasma current profiles for advanced physics research.
Area of Science:
- Plasma Physics
- Magnetohydrodynamics
- Electromagnetic Boundary Conditions
Background:
- Understanding plasma instabilities is crucial for fusion energy and astrophysical phenomena.
- Current-driven instabilities play a significant role in plasma confinement and behavior.
Purpose of the Study:
- To investigate the impact of electromagnetic boundary conditions on plasma instabilities.
- To study ideal and resistive magnetohydrodynamic instabilities using a rotating wall.
- To control plasma current profiles for stability research.
Main Methods:
- Construction and description of a rotating wall machine with screw pinch magnetic geometry.
- Utilizing an array of 19 independently biased plasma guns for plasma generation and current control.
- Employing internal probes and diagnostics to measure plasma properties.
Main Results:
- Demonstrated control over plasma current profiles via the plasma gun array.
- Characterized quiescent discharges exhibiting high beta (β), flow, and good collimation.
- Successfully implemented differentially rotating conducting walls to influence instabilities.
Conclusions:
- The rotating wall machine is a viable facility for studying electromagnetic boundary effects on plasma instabilities.
- Spatial and temporal control of plasma current profiles is achievable.
- Experimental results provide insights into current-driven magnetohydrodynamic instabilities.
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