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arXiv · 1803.10140

Bringing global gyrokinetic turbulence simulations to the transport timescale using a multiscale approach

Jeffrey B. Parker·Lynda L. LoDestro·Daniel Told·Gabriele Merlo·Lee F. Ricketson·Alejandro Campos·Frank Jenko·Jeffrey A. F. Hittinger
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Abstract

The vast separation dividing the characteristic times of energy confinement and turbulence in the core of toroidal plasmas makes first-principles prediction on long timescales extremely challenging. Here we report the demonstration of a multiple-timescale method that enables coupling global gyrokinetic simulations with a transport solver to calculate the evolution of the self-consistent temperature profile. This method, which exhibits resiliency to the intrinsic fluctuations arising in turbulence simulations, holds potential for integrating nonlocal gyrokinetic turbulence simulations into predictive, whole-device models.

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Jeffrey B. Parker, Lynda L. LoDestro, Daniel Told, Gabriele Merlo, Lee F. Ricketson, Alejandro Campos, Frank Jenko, Jeffrey A. F. Hittinger. 2018-03-27. Bringing global gyrokinetic turbulence simulations to the transport timescale using a multiscale approach. https://doi.org/10.1088/1741-4326%2Faab5c8

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