ELM control optimization for various ITER scenarios based on linear and quasi-linear figures of merit

Journal Article · Thu Apr 09 00:00:00 EDT 2020 · Physics of Plasmas

DOI:https://doi.org/10.1063/1.5139890· OSTI ID:1799657

Li, L. ^[1]; Liu, Y. Q. ^[2]; Loarte, A. ^[3]; Pinches, S. D. ^[3]; Polevoi, A. ^[3]; Zhong, F. C. ^[4]

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1. Donghua University, Shanghai (China); Donghua University, Shanghai, China
2. General Atomics, San Diego, California (United States)
3. ITER Organization, St. Paul Lez Durance (France)
4. Donghua University, Shanghai (China)

For the purpose of better understanding type-I edge localized mode (ELM) control in ITER with resonant magnetic perturbation (RMP) fields, the plasma response to RMP is computed by a resistive full magneto-hydrodynamic model in toroidal geometry. Five scenarios designed for ITER are considered, ranging from the pre-nuclear to nuclear phases. The plasma response to RMP is quantified by the plasma surface displacement near the X-point of the divertor plasma and at the outboard mid-plane. The optimal coil configurations between two high-Q deuterium-tritium (DT) scenarios (at the same plasma current of 15 MA and the same magnetic field of 5.3 T but different fusion gains, Q = 5 and 10) are predicted to be similar. For the other ITER scenarios with similar edge safety factor q₉₅ ~ 3 to that of the baseline scenario, the optimal coil phasing is also similar. The optimization results are different for a half-current full-field (7.5 MA/5.3 T) scenario, largely due to the difference in q₉₅. The RMP coil currents are also optimized to tailor the core vs edge toroidal torques exerted by the 3D RMP fields on the plasma column. Torque optimization, with various objective functions proposed in the study, is useful for minimizing the side effects of RMP on the plasma core flow in ITER, while still maintaining the ELM control capability. Full utilization of three rows of ELM control coils in ITER is found to be essential to ensure both flexibility and robustness of ELM control, in terms of both linear and quasilinear plasma responses.

• Research Organization: General Atomics, San Diego, CA (United States)
• Sponsoring Organization: USDOE Office of Science (SC)
• Grant/Contract Number: FC02-04ER54698; FG02-95ER54309
• OSTI ID: 1799657
• Journal Information: Physics of Plasmas, Journal Name: Physics of Plasmas Journal Issue: 4 Vol. 27; ISSN 1070-664X
• Publisher: American Institute of Physics (AIP)
• Country of Publication: United States
• Language: English

Related Subjects

70 PLASMA PHYSICS AND FUSION TECHNOLOGY
Magnetic confinement fusion
Magnetohydrodynamics
Physics
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