Extrapolation of DIII-D Steady-State Scenarios to ITER*

DIII-D is exploring a range of potential steady-state scenarios including high qmin, steady-state hybrid, and high li in the scaled ITER shape. The FASTRAN modeling self-consistent with core transport (TGLF), edge pedestal (EPED1), external heating/current drive (NUBEAM, TORAY), and low-n ideal/resistive stabilities (DCON, PEST3) has been tested extensively against these experiments, reproducing the measured density, temperature, rotation and current profiles reasonably well without any significant free parameters other than anomalous current diffusion in steady-state hybrid and uncertainty of the MHD-induced beam ion loss. Extrapolations to ITER from DIII-D using the same theory-based models show that the fusion performance Q increases rapidly with the density at the fully non-inductive condition, f_NI=1 in conjunction with the increased bootstrap current fraction and improved energy confinement. All three scenarios achieve Q>3 using the “Day-1” heating/current drive if the normalized density, n_e,ped/n_GW approaches to 1. An optimum choice of the H/CD upgrades for each scenario is investigated to achieve the f_NI=1 and Q=5 ITER mission.