How eigenmode self-interaction affects zonal flows and convergence of tokamak core turbulence with toroidal system size

  title={How eigenmode self-interaction affects zonal flows and convergence of tokamak core turbulence with toroidal system size},
  author={Ajay C. J. and Stephan Brunner and Ben F. McMillan and Justin Ball and Julien Dominski and Gabriele Merlo},
  journal={Journal of Plasma Physics},
Self-interaction is the process by which a microinstability eigenmode that is extended along the direction parallel to the magnetic field interacts non-linearly with itself. This effect is particularly significant in gyrokinetic simulations accounting for kinetic passing electron dynamics and is known to generate stationary $E\times B$ zonal flow shear layers at radial locations near low-order mode rational surfaces (Weikl et al. Phys. Plasmas, vol. 25, 2018, 072305). We find that self… 

A phase-shift-periodic parallel boundary condition for low-magnetic-shear scenarios

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Microtearing turbulence saturation via electron temperature flattening at low-order rational surfaces

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Large scale structures in the E × B shearing rate, known as staircases, are shown to form in nonlinear gyro-kinetic turbulence simulations with kinetic electrons. However, in many cases, a small

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The response of passing electrons in ion temperature gradient and trapped electron mode microturbulence regimes is investigated in tokamak geometry making use of the flux-tube version of the

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The effects of the finite Larmor radius on the generation of zonal flows by the four-wave modulational instability are investigated using an extended form of the Hasegawa-Mima equation. Growth rates

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Gyrokinetic simulation of multimode plasma turbulence. PhD thesis, Universität Münster

  • 2008

Eliminating turbulent self-interaction through the parallel boundary condition in local gyrokinetic simulations

In this work, we highlight an issue that may reduce the accuracy of many local nonlinear gyrokinetic simulations – turbulent self-interaction through the parallel boundary condition. Given a