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Updated: May 14, 2026
11:47
A 100 KW Class Applied-field Magnetoplasmadynamic Thruster
Published on: December 22, 2018
Toroidal magnetized plasma device with sheared magnetic field lines using an internal ring conductor
1Centre National de la Recherche Scientifique, UMR 7345 Laboratoire PIIM, Aix-Marseille Université, Marseille, France.
The Review of Scientific Instruments
|February 8, 2013
Summary
A new toroidal plasma device with a poloidal magnetic field enhances plasma density and suppresses turbulence. This finite rotational transform improves confinement, reducing diffusion compared to standard models.
Area of Science:
- Plasma physics
- Fusion energy research
- Magnetohydrodynamics
Background:
- Toroidal devices often suffer from turbulence and instabilities due to the absence of sheared magnetic fields.
- Efficient plasma confinement is crucial for fusion energy applications.
Purpose of the Study:
- To investigate plasma confinement efficiency and turbulence levels in a novel toroidal device.
- To evaluate the impact of a poloidal magnetic field on plasma characteristics.
Main Methods:
- Utilized a new toroidal laboratory plasma device with an internal conductor generating a poloidal magnetic field.
- Measured plasma density, decay time, and turbulence levels under varying magnetic field conditions.
Main Results:
- A significant enhancement in plasma density was observed with a sufficiently strong poloidal magnetic field.
- Finite rotational transform effectively suppressed instabilities and turbulence typical of devices lacking sheared magnetic fields.
- Particle confinement time was estimated and compared against Bohm diffusion and neoclassical diffusion models.
Conclusions:
- The poloidal magnetic field is key to improving plasma density and stability in toroidal devices.
- The studied device demonstrates enhanced plasma confinement, outperforming standard diffusion models.
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