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Update on hybrid scenario. J. Garcia. Association Euratom-CEA CEA, IRFM (France). Simulations of ITER hybrid scenario with the same scheme as in JET. I p = 11 MA , B T = 5.3 T dI p /dt= 0.18 MA/s , B T = 5.3 T, f G =0.4 during ramp-up. f G =0.85 flat-top phase
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Update on hybrid scenario J. Garcia Association Euratom-CEA CEA, IRFM (France)
Simulations of ITER hybrid scenario with the same scheme as in JET • Ip = 11 MA, BT = 5.3 T • dIp /dt= 0.18 MA/s, BT = 5.3 T, fG=0.4 during ramp-up. fG=0.85 flat-top phase • EC wave launch: top launchers, 8MW during ramp-up, 20MW flat-top • ICRH: 20 MW, NBI: 33MW (off-axis and on-axis) • ne profile fixed, picked profile, ne(0) ≈ 0.95 1020 m-3 • rped ≈ 0.95, nped≈ 0.55 1020 m-3, Tped 4.5 keV • Bohm-GyroBohm transpor tmodel during ramp-up • H98=1.3 with Bohm-GyroBohm shape for flat-top phase
ITER hybrid scenario simulation Fixed density (ne0/<ne>~1.4) Fixed T pedestal (~ 5 keV) Fixed H-factor (~ 1.3) Ip = 12 MA Padd ~ 73 MW Bootstrap fraction ~ 40% Non-inductive fraction ~ 80% Fusion gain Q ~ 8 Fusion Power (MW) ~ 585
ITER simulations • 8 MW of ECRH/ECCD during ramp-up are essential • Comparison with Dick’s work?
The physics in the background • By matching the current and heating configuration for JET and ITER very similar poloidal current profiles are obtained • The way is to reduce the current to have almost a flat profile at jθ=0 • The final state of the plasma is then very similar for both cases
ITER steady-state scenario simulation Fixed density (ne0/<ne>~1.4) Fixed T pedestal (~ 4.5 keV) Fixed H-factor (~ 1.4) Ip = 10 MA Padd ~ 90 MW Bootstrap fraction ~ 53% Non-inductive fraction ~ 100% Fusion gain Q ~ 5 Fusion Power (MW) ~ 425