Cross-polarization scattering of diffracting electron-cyclotron beams in a turbulent plasma with the WKBeam code

Joint Varenna-Lausanne International Workshop on the Theory of Fusion Plasmas 2016

Guidi, L.^1,2 ; Maj, O.^1 ; Weber, H.^1 ; Köhn, A.^1 ; Snicker, A.^1 ; Poli, E.^1

Max Planck Institute for Plasma Physics, Boltzmannstr. 2, Garching

85748, Germany^1

Technische Universität München, Numerical Methods for Plasmaphysics (M16), Boltzmannstr. 3, Garching

85748, Germany^2

关键词: Cross polarizations;    Density fluctuation;    Electron cyclotron waves;    Electron cyclotrons;    Numerical scheme;    Radiofrequency waves;    Turbulent plasmas;    Wave kinetic equations;   

Others  :  https://iopscience.iop.org/article/10.1088/1742-6596/775/1/012005/pdf
DOI  :  10.1088/1742-6596/775/1/012005

来源: IOP

【 摘 要 】

In turbulent plasmas, density fluctuations are expected to scatter radiofrequency wave beams, causing a degradation of the beam quality and thus reducing their performance. The WKBeam code is a Monte-Carlo solver for the wave kinetic equation, which describes such an effect, so far limited to a single wave mode so that it cannot account for cross-polarization scattering. In this work a new feature of the WKBeam code is presented, which allows the analysis of cross-polarization scattering of electron-cyclotron (EC) wave beams in realistic tokamak scenarios. We prove the convergence of the numerical scheme and give a preliminary overview of such effects in ITER scenarios.