New predictive capabilities in PTRANSP with PTSOLVER

A new implicit transport equation solver (PT-SOLVER) implemented in predictive TRANSP (PTRANSP) is used to integrate the highly nonlinear time-dependent transport equations using implicit Newton iteration methods. Capabilities are extended to include density and angular momentum prediction. The new solver allows users to choose between different transport models via a standard namelist input. A wide range of neoclassical and/or turbulent models or semi-empirical, including TGLF choices are available. Extensive benchmark test runs have been performed with PT-SOLVER using the TGLF parallelized over flux-surfaces and wavenumbers. A combined number of CPUs up to 128 have been used. The new solver is robust, efficient, and allows large time-steps to be used. PTRANSP predicted temperatures have also been compared with experimental data for various plasma regimes, and good agreement has been achieved.