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arXiv · 1702.00050

NIMROD Modeling of Quiescent H-mode: Reconstruction Considerations and Saturation Mechanism

J. R. King·K. H. Burrell·A. M. Garofalo·R. J. Groebner·S. E. Kruger·A. Y. Pankin·P. B. Snyder
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Abstract

The extended-MHD NIMROD code [C.R. Sovinec and J.R. King, J. Comput. Phys. 229, 5803 (2010)] models broadband-MHD activity from a reconstruction of a quiescent H-mode shot on the DIII-D tokamak [J. L. Luxon, Nucl. Fusion 42, 614 (2002)]. Computations with the reconstructed toroidal and poloidal ion flows exhibit low-n perturbations (n=1-5) that grow and saturate into a turbulent-like MHD state. The workflow used to project the reconstructed state onto the NIMROD basis functions re-solves the Grad-Shafranov equation and extrapolates profiles to include scrape-off-layer currents. Evaluation of the transport from the turbulent-like MHD state leads to a relaxation of the density and temperature profiles.

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J. R. King, K. H. Burrell, A. M. Garofalo, R. J. Groebner, S. E. Kruger, A. Y. Pankin, P. B. Snyder. 2017-01-31. NIMROD Modeling of Quiescent H-mode: Reconstruction Considerations and Saturation Mechanism. https://doi.org/10.1088/0029-5515/57/2/022002

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