Year: 2026
Type: preprint
Abstract: We present a novel mechanism for spontaneous shear-flow generation in the scrape-off layer (SOL) of magnetically confined plasmas, arising at abrupt changes in the sheath connection length $L_\parallel$. Such transitions occur naturally in the Wendelstein 7-X stellarator. Applying a critical balance treatment for interchange turbulence, we find that $L_\parallel$ sets the equilibrium pressure gradient and hence the radial electric field away from the transition, producing an $E\times B$ shear around the transition comparable to the turbulence growth rate. High-fidelity simulations are shown to be consistent with the theoretical prediction.
Source: arXiv (Cornell University)
Authors: Shanahan, Brendan, Rodriguez, Eduardo
Language: English
Subfield: Nuclear and High Energy Physics
Field: Physics and Astronomy
Domain: Physical Sciences
Open Access status: green
OpenAlex ID: W7223295589