1 / 23

MHD-GK Hybrid Simulation of Alfvenic Instabilities in Burning Plasmas

MHD-GK Hybrid Simulation of Alfvenic Instabilities in Burning Plasmas. Shuang-hui Hu Dept of Phys, Coll of Sci, Guizhou University Liu Chen IFTS, Zhejiang University Supported by NSFC. Motivation. Importance of Alfven wave and energetic particle physics in fusion plasmas

abner
Download Presentation

MHD-GK Hybrid Simulation of Alfvenic Instabilities in Burning Plasmas

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. MHD-GK Hybrid Simulationof Alfvenic Instabilitiesin Burning Plasmas Shuang-hui Hu Dept of Phys, Coll of Sci, Guizhou University Liu Chen IFTS, Zhejiang University Supported by NSFC

  2. Motivation • Importance of Alfven wave and energetic particle physics in fusion plasmas • Efficient access to the associated kinetic understandings with MHD-gyrokinetic hybrid simulations upon theoretical achievement on alfvenic activities • Key roles of kinetic excitations for varied alfvenic modes by different plasma components via wave-particle interactions

  3. Outline • Research objective • Theoretical model • Numerical scheme • Model for toroidal plasmas • Kinetically excited alfvenic instabilities • Model for dipolar plasmas • Kinetic excitation of Alfven waves • Summary

  4. Objective • To understand alfvenic instabilities and the supporting kinetic mechanisms • To demonstrate the alfvenic mode evolution upon basic physical correlations • To bridge the simplified numerical studies to large-scale numerical explorations • To serve a basic physical/numerical training for massive simulations

  5. Theoretical Model over Coupled MHD-GK Equations

  6. Theoretical Model (cont.)

  7. Field-Particle Hybrid Simulation • Field components within MHD description evolved with finite difference algorithm • Particle components within gyrokinetic description simulated with delta-f method • Coupling between field-on-grids and particle-on-continuous-trajectory communicated with PIC technique

  8. Numerical Scheme • The coupled MHD-gyrokinetic system advanced in time upon the given toroidal (azimuthal) wavenumber • Marker particles loaded over the given equilibrium distribution • Boundary condition applied with the vanished perturbations

  9. Toroidal Plasmas [Chen, 1994; Chen & Hasegawa, 1991]

  10. Alfven Continuum with Frequency Gap [Chen and Zonca, 1995]

  11. Alfven Modes in Toroidal Geometry • TAE: Frequencies inside the toroidal Alfven frequency gap EPM: Frequencies by particle frequencies via wave-particle resonance conditions alpha-TAE: Bound states in the potential wells due to the ballooning drive • Rich alfvenic activities, including low frequency continuum, in burning plasma conditions

  12. An Exampleon Wave-Particle Resonanceby Gyrokinetic Equation Gyrokinetic equation Trapped particle solution Resonance condition for trapped particles

  13. MHD Eigenmode Structures for Negative Magnetic Shear

  14. Kinetic Excitation by Trapped Particles (1,0)

  15. Kinetic Excitation by Trapped Particles (3,0)

  16. Kinetic Excitations by Circulating Particles

  17. Dipolar Plasmas [Frieman & Chen, 1982; Chen & Hasegawa, 1991]

  18. Dipolar Geometry

  19. 2D Eigenmode Structures

  20. Wave-Particle Resonances by

  21. Local MHD Frequencies

  22. Marker Particle Trajectory in Nonlinear Phase

  23. Summary • MHD-gyrokinetic hybrid simulation codes are developed to investigate alfvenic instabilities under the burning plasma conditions. • Kinetic excitation mechanisms are studied upon varied wave-particle resonances for different particle species. Further nonlinear studies are prompted upon the detailed understandings of alfvenic modes within the continuum spectrum or frequency gap under the conditions with multiple particle species.

More Related