Numerical Simulation of Non-inductive Startup in the Pegasus Toroidal Experiment

POSTER

Abstract

Nonlinear numerical computation is used to investigate DC helicity injection from washer-gun plasma sources in the Pegasus Toroidal Experiment (Univ. of Wisconsin). Resistive MHD simulations with the NIMROD code (nimrodteam.org) are used to model non-inductive startup, with emphasis on the relaxation of the non-axisymmetric current channels into a ``tokamak-like'' plasma. Simulations utilize fully three-dimensional, anisotropic, temperature-dependent thermal conductivity corrected for regions of low-magnetization [Braginskii, Reviews of Plasma Physics, 1965], temperature-dependent resistivity, and Ohmic heating. Off-diagonal Fourier-component coupling is investigated as a means of improving preconditioning of the temperature advance.

*Work Supported by the U.S. Dept. of Energy

Authors

  • J.B. O'Bryan

    • University of Wisconsin--Madison

  • C.R. Sovinec

    • University of Wisconsin - Madison
    • Univ. of Wisconsin-Madison
    • University of Wisconsin-Madison
    • University of Wisconsin--Madison
    • University of Wisconsin, Madison
    • U. Wisc.

  • Tom Bird

    • University of Wisconsin--Madison
    • University of Wisconsin - Madison