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arXiv · 1110.0747

Dynamic Procedure for Filtered Gyrokinetic Simulations

Pierre Morel·Alejandro Bañón Navarro·Michel Albrecht-Marc·Daniele Carati·Florian Merz·Tobias Görler·Frank Jenko
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Abstract

Large Eddy Simulations (LES) of gyrokinetic plasma turbulence are investigated as interesting candidates to decrease the computational cost. A dynamic procedure is implemented in the GENE code, allowing for dynamic optimization of the free parameters of the LES models (setting the amplitudes of dissipative terms). Employing such LES methods, one recovers the free energy and heat flux spectra obtained from highly resolved Direct Numerical Simulations (DNS). Systematic comparisons are performed for different values of the temperature gradient and magnetic shear, parameters which are of prime importance in Ion Temperature Gradient (ITG) driven turbulence. Moreover, the degree of anisotropy of the problem, that can vary with parameters, can be adapted dynamically by the method that shows Gyrokinetic Large Eddy Simulation (GyroLES) to be a serious candidate to reduce numerical cost of gyrokinetic solvers.

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Pierre Morel, Alejandro Bañón Navarro, Michel Albrecht-Marc, Daniele Carati, Florian Merz, Tobias Görler, Frank Jenko. 2011-10-04. Dynamic Procedure for Filtered Gyrokinetic Simulations. https://doi.org/10.1063/1.3677366

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