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Intermittent transport in edge plasmas

Odd Erik Garcia·Volker Naulin·Anders Henry Nielsen·Jens Juul Rasmussen
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Abstract

The properties of low-frequency convective fluctuations and transport are investigated for the boundary region of magnetized plasmas. We employ a two-dimensional fluid model for the evolution of the global plasma quantities in a geometry and with parameters relevant to the scrape-off layer of confined toroidal plasmas. Strongly intermittent plasma transport is regulated by self-consistently generated sheared poloidal flows and is mediated by bursty ejection of particles and heat from the bulk plasma in the form of blobs. Coarse grained probe signals reveal a highly skewed and flat distribution on short time scales, but tends towards a normal distribution at large time scales. Conditionally averaged signals are in perfect agreement with experimental measurements.

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Odd Erik Garcia, Volker Naulin, Anders Henry Nielsen, Jens Juul Rasmussen. 2004-10-19. Intermittent transport in edge plasmas. https://arxiv.org/abs/physics/0410153

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