Effect of parallel convection on divertor plasma turbulence driven by the current-convective instability in DIII-D-like detached conditions

POSTER

Abstract

It has been recently suggested [Krasheninnikov and Smolyakov, PoP, 2016] that the current-convective instability (CCI) can be responsible for formation of strong radiation fluctuations observed during the fluctuating state of detachment in experiments at ASDEX Upgrade (AUG) [Potzel et al., Nuclear Fusion, 2014]. The first numerical simulations of CCI dynamics, employing the basic physical model of the instability, have shown that this mechanism can indeed be a plausible candidate for the onset of turbulence with temporal parameters similar to those observed at AUG [Stepanenko and Krasheninnikov, PoP, 2018]. In this contribution we demonstrate the results of modeling the current-convective turbulence in detached plasma within the extended physical model of the CCI, incorporating the effect of parallel plasma convection in the diffusion approximation. We show the frequency spectra of saturated turbulence in the DIII-D-like detached conditions and compare them with the available experimental data and simulation data obtained within the basic physical model of the instability.


Presenters

  • Alexander Stepanenko

    Natl Research Nuclear University (MEPhI)

Authors

  • Alexander Stepanenko

    Natl Research Nuclear University (MEPhI)

  • Huiqian Wang

    Oak Ridge Associated Universities, General Atomics - San Diego, Oak Ridge Associated University, ORAU, Oak Ridge, TN, USA, Oak Ridge Associated Universities, USA, Oak Ridge Associated Universities, USA, General Atomics

  • Sergei Krasheninnikov

    Univ of California - San Diego, General Atomics / ORAU, University of California, San Diego