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Model for current-driven edge-localized modes
C G Gimblett1, R J Hastie, P Helander
1EURATOM/UKAEA Fusion Association, Culham Science Centre, Abingdon, Oxon, OX14 3DB, United Kingdom. chris.gimblet@ukaea.org.uk
Physical Review Letters
|February 21, 2006
Summary
This study models edge-localized modes (ELMs) in tokamak plasmas using Taylor relaxation initiated by toroidal peeling modes. The model predicts ELM energy losses and matches experimental observations of plasma behavior.
Area of Science:
- Plasma physics
- Fusion energy research
- Magnetohydrodynamics
Background:
- Edge-localized modes (ELMs) are crucial cyclic plasma disturbances affecting tokamak performance.
- Understanding ELMs is vital for advancing future tokamak reactors.
Purpose of the Study:
- To develop a novel model for edge-localized modes (ELMs) in tokamak plasmas.
- To investigate the role of toroidal peeling modes and Taylor relaxation in ELM dynamics.
Main Methods:
- Modeling ELMs by initiating Taylor relaxation of the tokamak's outer plasma region.
- Analyzing the interplay between destabilizing edge current profiles and stabilizing plasma-vacuum current sheets.
Main Results:
- The model predicts energy losses associated with ELMs.
- It reproduces experimentally observed variations with edge safety factor and plasma collisionality.
- An intrinsic "deterministic scatter" in the model aligns with experimental data.
Conclusions:
- The Taylor relaxation model provides a framework for understanding ELM behavior.
- This approach offers predictive capabilities for ELM energy losses and dependencies.
- The model's agreement with experimental data validates its utility in fusion research.
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