Simulating W Impurity Transport in Tokamaks

POSTER

Abstract

The extreme heat and charged particle flux to plasma facing materials in magnetically confined fusion devices has motivated Tungsten experiments such as the ``W-Ring'' experiment on the DIII-D tokamak to investigate W divertor viability. In this domain, the transport of W impurities from their tile locations to other first-wall tiles is highly relevant to material lifetimes and tokamak operation. Here we present initial results from a simulation of this W transport. Given that sputtered impurities may experience prompt redeposition near the divertor strikepoint, or migrate far from its origin to the midplane, there is a need to track the global, 3-D, impurity redistribution. This is done by directly integrating the 6-D Lorentz equation of motion (plus thermal gradient terms and relevant Monte-Carlo operators) for the impurity ions and neutrals under background plasma parameters determined by the SOLPS edge plasma code. The geometric details of the plasma facing components are represented to a fidelity sufficient to examine the global impurity migration trends with initial work also presented on advanced surface meshing capabilities targeting high fidelity simulation.

*This work is supported by U.S. DOE Office of Science SciDAC project on plasma-surface interactions under US DOE contract DE-AC05-00OR22725.

Authors

  • Timothy R. Younkin

    • University of Tennessee
  • David L. Green

    • Oak Ridge National Lab
  • A. Lasa

    • Oak Ridge National Lab
    • ORNL
  • J.M. Canik

    • ORNL
    • Oak Ridge National Lab
    • Oak Ridge National Laboratory
  • Brian D. Wirth

    • University of Tennessee