Turbulent Optimization of Toroidal Configurations
Authors: H. Mynick, et. al.
Abstract:
Recent progress in "turbulent optimization" of toroidal configurations is described,
using a method recently developed for evolving such configurations to ones having reduced
turbulent transport. The method uses the Gene gyrokinetic code to compute
the radial heat flux Qgk, and the Stellopt optimization code with a theory-based
"proxy" figure of merit Qpr to stand in for Qgk for computational speed. Improved
expressions for Qpr have been developed, involving further geometric quantities beyond
those in the original proxy, which can also be used as "control knobs" to reduce
Qgk. Use of a global search algorithm has led to the discovery of turbulent-optimized
configurations not found by the standard, local algorithm usually employed, as has
use of a mapping capability which Stellopt has been extended to provide, of figures
of merit over the search space.
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Published in: Plasma Physics and Controlled Fusion 56 (2014) 094001 (7pp)
doi:10.1088/0741-3335/56/9/094001
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