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Updated: May 20, 2026
11:47
A 100 KW Class Applied-field Magnetoplasmadynamic Thruster
Published on: December 22, 2018
Magnetic bucket for rotating unmagnetized plasma.
Noam Katz1, Cami Collins, John Wallace
1Department of Physics, University of Wisconsin, Madison, Wisconsin 53706, USA. nkatz2@wisc.edu
The Review of Scientific Instruments
|July 5, 2012
Summary
Researchers generated plasma flow using a novel magnetic bucket confinement system. This experiment drives toroidal rotation via J × B forces, achieving edge speeds of 3 km/s and coupling to the core plasma.
Area of Science:
- Plasma physics
- Magnetic confinement fusion
- Experimental plasma dynamics
Background:
- Traditional magnetic confinement struggles with plasma stability and confinement.
- Generating controlled plasma flow is crucial for various applications, including fusion energy.
Purpose of the Study:
- To describe a new experimental method for generating flow in unmagnetized plasma.
- To investigate the effectiveness of a magnetic bucket configuration for plasma confinement and rotation.
- To analyze the conditions and power balance required for sustained plasma rotation.
Main Methods:
- Utilized a magnetic bucket, an axisymmetric, high-order multipolar magnetic field configuration.
- Implemented J × B forces at the magnetized edge to drive toroidal rotation.
- Employed anodes and thermionic cathodes for cross-field current generation.
- Measured edge rotation speeds up to 3 km/s.
- Applied a 0-dimensional power balance model for confinement analysis.
Main Results:
- Successfully generated and sustained toroidal plasma flow in an unmagnetized core.
- Achieved edge plasma rotation speeds of 3 km/s.
- Demonstrated viscous coupling between the rotating edge and the unmagnetized core.
- Identified key conditions necessary for initiating and maintaining plasma rotation.
Conclusions:
- The magnetic bucket configuration is effective for confining and generating flow in plasma.
- J × B forces provide a viable mechanism for driving toroidal rotation.
- Understanding the power balance is essential for optimizing plasma confinement and performance in such devices.
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