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arXiv · 1203.1571

Global Gyrokinetic Simulation of Tokamak Edge Pedestal Instabilities

Weigang Wan·Scott E. Parker·Yang Chen·Zheng Yan·Richard J. Groebner·Philip B. Snyder
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Abstract

Global electromagnetic gyrokinetic simulations show the existence of near threshold conditions for both a high-$n$ kinetic ballooning mode (KBM) and an intermediate-$n$ kinetic version of peeling-ballooning mode (KPBM) in the edge pedestal of two DIII-D H-mode discharges. When the magnetic shear is reduced in a narrow region of steep pressure gradient, the KPBM is significantly stabilized, while the KBM is weakly destabilized and hence becomes the most-unstable mode. Collisions decrease the KBM's critical $β$ and increase the growth rate.

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Weigang Wan, Scott E. Parker, Yang Chen, Zheng Yan, Richard J. Groebner, Philip B. Snyder. 2012-09-26. Global Gyrokinetic Simulation of Tokamak Edge Pedestal Instabilities. https://doi.org/10.1103/physrevlett.109.185004

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