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Updated: May 24, 2026
06:42
Magnetically Induced Rotating Rayleigh-Taylor Instability
Published on: March 3, 2017
Transport-driven toroidal rotation in the tokamak edge
1Max-Planck-Institut für Plasmaphysik, EURATOM Association, Garching, Germany. tstoltzf@ipp.mpg.de
Physical Review Letters
|March 10, 2012
Summary
Passing-ion drift orbits interacting with radial transport cause spontaneous toroidal spin-up in tokamak edge models. This phenomenon, driven by orbit shifts and leading to residual stress, influences plasma rotation, with X-points further modifying rotation direction.
Area of Science:
- Plasma physics
- Fusion energy research
- Tokamak edge physics
Background:
- Tokamak devices are crucial for fusion energy research.
- Understanding plasma rotation is key to controlling tokamak performance.
- The tokamak edge plasma is complex and influences overall stability.
Purpose of the Study:
- To investigate the mechanism of spontaneous toroidal spin-up in tokamak edge models.
- To analyze the role of passing-ion drift orbits and radial transport in generating intrinsic rotation.
- To explore how plasma parameters and magnetic geometry affect rotation.
Main Methods:
- Development of a simple theoretical model for tokamak edge plasma.
- Analysis of the interaction between passing-ion drift orbits and diffusive radial transport.
- Examination of orbit-averaged diffusivities dependence on v(∥) and residual stress generation.
Main Results:
- Demonstrated spontaneous toroidal spin-up due to the interaction of drift orbits and radial transport.
- Identified that major-radial orbit shifts cause v(∥)-dependent diffusivities, leading to residual stress.
- Observed intrinsic rotation scaling with T(i)/B(θ) at the pedestal top.
- Found that inboard (outboard) X-points enhance co- (counter)current rotation.
Conclusions:
- The study provides a physical mechanism for intrinsic rotation generation in tokamak edge plasmas.
- The model successfully reproduces key experimental scalings of intrinsic rotation.
- Magnetic geometry, specifically X-point location, significantly impacts plasma rotation, offering potential control knobs.
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