Modeling the effect of hydrogen line radiation on partially ionized plasma transport

M.L. Adams1), H.A. Scott1)

1) Lawrence Livermore National Laboratory, Livermore, CA 94550, USA

Hydrogen resonance lines can be very optically thick in the plasma at the tokamak edge. As a result, nonlocal energy transport by radiation within the plasma becomes important and significantly alters the ionization and energy balance in these systems. One method of including this effect is to self-consistently couple a partially ionized plasma transport model with a nonlocal thermodynamic equilibrium (NLTE) model incorporating line radiation transfer. This approach has been implemented in one dimension, but would be computationally challenging and expensive to implement in multiple dimensions. Approximate treatments of radiation transfer can decrease the computational time, but would still require coupling to a multidimensional plasma transport model to address realistic tokamak geometries. Here we identify the dominant atomic processes and radiation effects from detailed simulations, and consider the development of atomic hydrogen data tables that both include radiation effects and can be easily applied to complex geometries.


This work was performed under the auspices of the U.S. Department of Energy, by the University of California, Lawrence Livermore National Laboratory under contract W-7405-ENG-48. UCRL-ABS-205572