Session KP01 - Poster Session III.
POSTER session, Tuesday afternoon, March 23
Exhibit Hall, GWCC
A series of lower hybrid (LH) experiments is being started on the MST RFP with an ultimate goal of improving plasma confinement via current profile control. To facilitate this endeavor, we are enhancing the capability of the RFP version of ray-tracing and Fokker-Planck simulation codes (GENRAY and CQL3D). This paper will focus on numerical studies of two physical effects: DC electric field and radial transport. The electric field may increase the current drive (CD) efficiency by a synergetic effect with LH waves, as well as by the knock-on, large-angle scattering process (V. S. Chan et al., in Proc. of ISPP, Varenna, Italy, 1998.). This is modeled with DC electric field and knock-on source terms in the bounce-averaged Fokker-Planck equation. On the other hand, moderately large radial transport in the RFP has adverse effects on LHCD. This is being studied by adding a velocity dependent radial diffusion term along with a pinch term which ensures particle conservation.