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arXiv · 1502.05494

Inertial blob-hole symmetry breaking in magnetised plasma filaments

Alexander Kendl
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Abstract

Symmetry breaking between the propagation velocities of magnetised plasma filaments with large positive (blob) and negative (hole) amplitudes, as implied by a dimensional analysis scaling, is studied with global ("full-n") non-Boussinesq gyrofluid computations, which include finite inertia effects through nonlinear polarisation. Interchange blobs on a flat density background have higher inertia and propagate more slowly than holes. In the presence of a large enough density gradient, the effect is reversed: blobs accelerate down the gradient and holes are slowed in their propagation up the gradient. Drift wave blobs spread their initial vorticity rapidly into a fully developed turbulent state, whereas primary holes can remain coherent for many eddy turnover times. The results bear implications for plasma edge zonal flow evolution and tokamak scrape-off-layer transport.

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Alexander Kendl. 2015-02-19. Inertial blob-hole symmetry breaking in magnetised plasma filaments. https://doi.org/10.1088/0741-3335%2F57%2F4%2F045012

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