Improved high-performance fully non-inductive discharge by optimizing the fast-ion confinement on EAST

EAST Team, J. Huang*, J.P. Qian, A.M. Garofalo, X.Z. Gong, C.R. Wu, J.F. Chang, J. Zhang, H.F. Du, M.Q. Wu, B.L. Hao, L.M. Yu, X.M. Zhang, B. Madsen, Mirko Salewski, L.Z. Liang, J. Li, S.Y. Ding, G.Q. Zhong, J.L. Chen & 13 others X. Zhu, L. Zeng, E.Z. Li, B. Zhang, Z. Xu, J.X. Su, W. Gao, Y.J. Chen, Y.Y. Li, H. Liu, B. Lyu, Q. Zang, B. Wan

*Corresponding author for this work

Research output: Contribution to journalJournal articleResearchpeer-review

Abstract

The attainment of long-pulse, high-performance, fully non-inductive plasma is one of the major scientific objectives of EAST, using the ITER-like tungsten upper divertor. Understanding and optimizing the fast-ion behaviors is the critical issue to extending the performance of EAST. Recently, using both neutral beam injection (NBI) and radio frequency (RF; low hybrid, electron cyclotron, and ion cyclotron) heating, fully non-inductive high-βP scenarios with extension of fusion performance at high density and low rotation have been achieved, with βP  up to 2.5, βN up to 2.0, H98y 2  >  1.1, and bootstrap current fraction (f BS) up to 50%. For previous long-pulse H-mode plasma at medium density, when NBI is added into RF plasma, β is increased from 1.2 to 2.0 compared with RF-only discharges. In fact, f BS for both discharges is nearly the same, at ~22%. Analysis shows that the increase in βp is mostly due to fast ions which do not contribute significantly to the neoclassical bootstrap current. Thus, to obtain high-performance plasmas with improved bootstrap current fraction, key parameters (e.g. density, beam energy, etc.) must be further optimized. Experimental results show that high density improves bootstrap fraction also by reducing fast-ion slowing-down time and loss. The lower beam energy also mitigates fast-ion loss, which is better for heating and CD performance. The extension of high-performance, fully non-inductive experiments on EAST at high density and zero/low NBI torque can potentially offer unique contributions towards ITER and CFETR.
Original languageEnglish
Article number016002
JournalNuclear Fusion
Volume60
Issue number1
Number of pages10
ISSN0029-5515
DOIs
Publication statusPublished - 2020

Keywords

  • Magnetic fusion
  • Fully non-inductive tokamak
  • Fast-ion behavior
  • Neutral beam

Cite this

EAST Team, Huang, J., Qian, J. P., Garofalo, A. M., Gong, X. Z., Wu, C. R., ... Wan, B. (2020). Improved high-performance fully non-inductive discharge by optimizing the fast-ion confinement on EAST. Nuclear Fusion, 60(1), [016002]. https://doi.org/10.1088/1741-4326/ab443a
EAST Team ; Huang, J. ; Qian, J.P. ; Garofalo, A.M. ; Gong, X.Z. ; Wu, C.R. ; Chang, J.F. ; Zhang, J. ; Du, H.F. ; Wu, M.Q. ; Hao, B.L. ; Yu, L.M. ; Zhang, X.M. ; Madsen, B. ; Salewski, Mirko ; Liang, L.Z. ; Li, J. ; Ding, S.Y. ; Zhong, G.Q. ; Chen, J.L. ; Zhu, X. ; Zeng, L. ; Li, E.Z. ; Zhang, B. ; Xu, Z. ; Su, J.X. ; Gao, W. ; Chen, Y.J. ; Li, Y.Y. ; Liu, H. ; Lyu, B. ; Zang, Q. ; Wan, B. / Improved high-performance fully non-inductive discharge by optimizing the fast-ion confinement on EAST. In: Nuclear Fusion. 2020 ; Vol. 60, No. 1.
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abstract = "The attainment of long-pulse, high-performance, fully non-inductive plasma is one of the major scientific objectives of EAST, using the ITER-like tungsten upper divertor. Understanding and optimizing the fast-ion behaviors is the critical issue to extending the performance of EAST. Recently, using both neutral beam injection (NBI) and radio frequency (RF; low hybrid, electron cyclotron, and ion cyclotron) heating, fully non-inductive high-βP scenarios with extension of fusion performance at high density and low rotation have been achieved, with βP  up to 2.5, βN up to 2.0, H98y 2  >  1.1, and bootstrap current fraction (f BS) up to 50{\%}. For previous long-pulse H-mode plasma at medium density, when NBI is added into RF plasma, βP  is increased from 1.2 to 2.0 compared with RF-only discharges. In fact, f BS for both discharges is nearly the same, at ~22{\%}. Analysis shows that the increase in βp is mostly due to fast ions which do not contribute significantly to the neoclassical bootstrap current. Thus, to obtain high-performance plasmas with improved bootstrap current fraction, key parameters (e.g. density, beam energy, etc.) must be further optimized. Experimental results show that high density improves bootstrap fraction also by reducing fast-ion slowing-down time and loss. The lower beam energy also mitigates fast-ion loss, which is better for heating and CD performance. The extension of high-performance, fully non-inductive experiments on EAST at high density and zero/low NBI torque can potentially offer unique contributions towards ITER and CFETR.",
keywords = "Magnetic fusion, Fully non-inductive tokamak, Fast-ion behavior, Neutral beam",
author = "{EAST Team} and J. Huang and J.P. Qian and A.M. Garofalo and X.Z. Gong and C.R. Wu and J.F. Chang and J. Zhang and H.F. Du and M.Q. Wu and B.L. Hao and L.M. Yu and X.M. Zhang and B. Madsen and Mirko Salewski and L.Z. Liang and J. Li and S.Y. Ding and G.Q. Zhong and J.L. Chen and X. Zhu and L. Zeng and E.Z. Li and B. Zhang and Z. Xu and J.X. Su and W. Gao and Y.J. Chen and Y.Y. Li and H. Liu and B. Lyu and Q. Zang and B. Wan",
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EAST Team, Huang, J, Qian, JP, Garofalo, AM, Gong, XZ, Wu, CR, Chang, JF, Zhang, J, Du, HF, Wu, MQ, Hao, BL, Yu, LM, Zhang, XM, Madsen, B, Salewski, M, Liang, LZ, Li, J, Ding, SY, Zhong, GQ, Chen, JL, Zhu, X, Zeng, L, Li, EZ, Zhang, B, Xu, Z, Su, JX, Gao, W, Chen, YJ, Li, YY, Liu, H, Lyu, B, Zang, Q & Wan, B 2020, 'Improved high-performance fully non-inductive discharge by optimizing the fast-ion confinement on EAST', Nuclear Fusion, vol. 60, no. 1, 016002. https://doi.org/10.1088/1741-4326/ab443a

Improved high-performance fully non-inductive discharge by optimizing the fast-ion confinement on EAST. / EAST Team; Huang, J.; Qian, J.P.; Garofalo, A.M.; Gong, X.Z.; Wu, C.R.; Chang, J.F.; Zhang, J.; Du, H.F.; Wu, M.Q.; Hao, B.L.; Yu, L.M.; Zhang, X.M.; Madsen, B.; Salewski, Mirko; Liang, L.Z.; Li, J.; Ding, S.Y.; Zhong, G.Q.; Chen, J.L.; Zhu, X.; Zeng, L.; Li, E.Z.; Zhang, B.; Xu, Z.; Su, J.X.; Gao, W.; Chen, Y.J.; Li, Y.Y.; Liu, H.; Lyu, B.; Zang, Q.; Wan, B.

In: Nuclear Fusion, Vol. 60, No. 1, 016002, 2020.

Research output: Contribution to journalJournal articleResearchpeer-review

TY - JOUR

T1 - Improved high-performance fully non-inductive discharge by optimizing the fast-ion confinement on EAST

AU - EAST Team

AU - Huang, J.

AU - Qian, J.P.

AU - Garofalo, A.M.

AU - Gong, X.Z.

AU - Wu, C.R.

AU - Chang, J.F.

AU - Zhang, J.

AU - Du, H.F.

AU - Wu, M.Q.

AU - Hao, B.L.

AU - Yu, L.M.

AU - Zhang, X.M.

AU - Madsen, B.

AU - Salewski, Mirko

AU - Liang, L.Z.

AU - Li, J.

AU - Ding, S.Y.

AU - Zhong, G.Q.

AU - Chen, J.L.

AU - Zhu, X.

AU - Zeng, L.

AU - Li, E.Z.

AU - Zhang, B.

AU - Xu, Z.

AU - Su, J.X.

AU - Gao, W.

AU - Chen, Y.J.

AU - Li, Y.Y.

AU - Liu, H.

AU - Lyu, B.

AU - Zang, Q.

AU - Wan, B.

PY - 2020

Y1 - 2020

N2 - The attainment of long-pulse, high-performance, fully non-inductive plasma is one of the major scientific objectives of EAST, using the ITER-like tungsten upper divertor. Understanding and optimizing the fast-ion behaviors is the critical issue to extending the performance of EAST. Recently, using both neutral beam injection (NBI) and radio frequency (RF; low hybrid, electron cyclotron, and ion cyclotron) heating, fully non-inductive high-βP scenarios with extension of fusion performance at high density and low rotation have been achieved, with βP  up to 2.5, βN up to 2.0, H98y 2  >  1.1, and bootstrap current fraction (f BS) up to 50%. For previous long-pulse H-mode plasma at medium density, when NBI is added into RF plasma, βP  is increased from 1.2 to 2.0 compared with RF-only discharges. In fact, f BS for both discharges is nearly the same, at ~22%. Analysis shows that the increase in βp is mostly due to fast ions which do not contribute significantly to the neoclassical bootstrap current. Thus, to obtain high-performance plasmas with improved bootstrap current fraction, key parameters (e.g. density, beam energy, etc.) must be further optimized. Experimental results show that high density improves bootstrap fraction also by reducing fast-ion slowing-down time and loss. The lower beam energy also mitigates fast-ion loss, which is better for heating and CD performance. The extension of high-performance, fully non-inductive experiments on EAST at high density and zero/low NBI torque can potentially offer unique contributions towards ITER and CFETR.

AB - The attainment of long-pulse, high-performance, fully non-inductive plasma is one of the major scientific objectives of EAST, using the ITER-like tungsten upper divertor. Understanding and optimizing the fast-ion behaviors is the critical issue to extending the performance of EAST. Recently, using both neutral beam injection (NBI) and radio frequency (RF; low hybrid, electron cyclotron, and ion cyclotron) heating, fully non-inductive high-βP scenarios with extension of fusion performance at high density and low rotation have been achieved, with βP  up to 2.5, βN up to 2.0, H98y 2  >  1.1, and bootstrap current fraction (f BS) up to 50%. For previous long-pulse H-mode plasma at medium density, when NBI is added into RF plasma, βP  is increased from 1.2 to 2.0 compared with RF-only discharges. In fact, f BS for both discharges is nearly the same, at ~22%. Analysis shows that the increase in βp is mostly due to fast ions which do not contribute significantly to the neoclassical bootstrap current. Thus, to obtain high-performance plasmas with improved bootstrap current fraction, key parameters (e.g. density, beam energy, etc.) must be further optimized. Experimental results show that high density improves bootstrap fraction also by reducing fast-ion slowing-down time and loss. The lower beam energy also mitigates fast-ion loss, which is better for heating and CD performance. The extension of high-performance, fully non-inductive experiments on EAST at high density and zero/low NBI torque can potentially offer unique contributions towards ITER and CFETR.

KW - Magnetic fusion

KW - Fully non-inductive tokamak

KW - Fast-ion behavior

KW - Neutral beam

U2 - 10.1088/1741-4326/ab443a

DO - 10.1088/1741-4326/ab443a

M3 - Journal article

VL - 60

JO - Nuclear Fusion

JF - Nuclear Fusion

SN - 0029-5515

IS - 1

M1 - 016002

ER -