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Intermittency and turbulence in a magnetically confined fusion plasma
Carbone1, Sorriso-Valvo, Martines
1Dipartimento di Fisica, Universita degli studi della Calabria, 87036 Rende (CS), ItalyIstituto Nazionale di Fisica della Materia, Unita di Cosenza, 87036 Italy.
Summary
Magnetic turbulence in reversed field pinch plasmas exhibits intermittency, with smaller scales showing more significant deviations. Intermittency increases near the confinement device wall.
Area of Science:
- Plasma physics
- Magnetohydrodynamics
- Turbulence
Background:
- Magnetic turbulence is a key phenomenon in magnetically confined plasmas.
- Understanding turbulence intermittency is crucial for plasma confinement and stability.
Purpose of the Study:
- To investigate the intermittency of magnetic turbulence in reversed field pinch (RFP) plasmas.
- To analyze the scale-invariant properties of magnetic field differences.
- To examine the spatial distribution of intermittency within the plasma confinement device.
Main Methods:
- Analysis of magnetic field data from RFP experiments.
- Calculation of probability distribution functions (PDFs) of magnetic field differences.
- Investigation of scaling laws and deviations from scale invariance.
Main Results:
- PDFs of magnetic field differences are not scale-invariant, indicating intermittency.
- The wings of the PDFs are more significant at smaller scales, a signature of intermittency.
- Scaling laws are observed near the plasma confinement device wall.
- Intermittency of magnetic turbulence increases as measurements approach the external wall.
Conclusions:
- Reversed field pinch plasmas exhibit intermittent magnetic turbulence.
- Intermittency is a scale-dependent phenomenon, more pronounced at smaller scales.
- The plasma-wall interaction region is characterized by enhanced magnetic turbulence intermittency.
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