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arXiv · 1706.08406

Flow Shear Suppression of Pedestal Turbulence--A First Principles Theoretical Framework

D. R. Hatch·R. D. Hazeltine·M. K. Kotschenreuther·S. M. Mahajan
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Abstract

A combined analytic and computational gyrokinetic approach is developed to address the question of the scaling of pedestal turbulent transport with arbitrary levels of $E \times B$ shear. Due to strong gradients and shaping in the pedestal, the instabilities of interest are not curvature-driven like the core instabilities. By extensive numerical (gyrokinetic) simulations, it is demonstrated that pedestal modes respond to shear suppression very much like the predictions of a basic analytic decorrelation theory. The quantitative agreement between the two provides us with a new dependable, first principles (physics based) theoretical framework to predict the efficacy of shear suppression in burning plasmas that lie in a low-shear regime not accessed by present experiments.

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D. R. Hatch, R. D. Hazeltine, M. K. Kotschenreuther, S. M. Mahajan. 2017-06-26. Flow Shear Suppression of Pedestal Turbulence--A First Principles Theoretical Framework. https://doi.org/10.1088/1361-6587/aac7a7

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