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DOE OSTI · 2203575

Plasmoid-mediated reconnection during nonlinear peeling–ballooning edge-localized modes

Ebrahimi, Fatima·Bhattacharjee, Amitava
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Abstract

Abstract Plasmoid-mediated reconnection is investigated for nonlinear peeling–ballooning edge-localized modes (P-B ELMs). The formation of current sheets and the transition to 3D current sheet instability is demonstrated through fully nonlinear resistive MHD simulations of P-B ELMs in DIII-D discharges. Large-scale axisymmetric current sheets, as well as small-scale poloidally extended current sheets, are formed as the coherent P-B ELM filaments nonlinearly evolve. It is observed that, at high Lundquist numbers, these current sheets break during a reconnection burst, i.e. a secondary exponential growth of intermediate modes followed by relaxation due to the suppression of P-B drive.

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70 PLASMA PHYSICS AND FUSION TECHNOLOGYELMMHDedge instabilityfusionreconnectiontokamak

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Ebrahimi, Fatima, Bhattacharjee, Amitava. 2023-10-25. Plasmoid-mediated reconnection during nonlinear peeling–ballooning edge-localized modes. https://doi.org/10.1088/1741-4326%2Fad0062

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