JT-60U Status and Plans

FPPC , March 4, JAERI-DOE

M. Kikuchi for the JT-60 Team Japan Atomic Energy Research Institute 1. Uniﬁcation of JAERI and JNC

JAERI (Japan atomic Energy Research Institute) and JNC (Japan Nuclear Fuel Cycle-Development Institute) will be uniﬁed to form a new entity in Mid 2005. Present staff and budget of two institutes as of 2003 are as follows.

JAERI employs ~2,200 staff budget ~ 94 billion Yen. President of JAERI T. Okazaki from JNC employs ~2,300 staff JAERI HP budget ~ 130 billion Yen. Procedures for personal assignment

ITPA Joint experiments US to JT-60U : LT IA Appendix A2 signed by E. Oktay and Visitor EU to JT-60U : LT IA Appendix A2 signed by M. Watkins and Visitor JT-60U to US : Personal assignment agreement (US-J) is required except PPPL and GA. JT-60U to EU : Personal assignment agreement (EU-J) is required except JET.

IEA Large Tokamak Agreement (EURATOM, JAERI,DOE, 1986)

AT Agreement Doublet III Agreement (IPP-JAERI),2004? (DOE-JAERI) 1979

EURATOM-Japan agreement US-Japan agreement on on cooperation in fusion, 1989 cooperation in R&D in energy ﬁelds, 1979 National research collaboration

Research Theme structure for 2003–2004

Director of Department of Fusion Plasma Res.

Theme Leaders; (T. Fujita ), S. Ide, H. Takenaga Task

Extension of Discharge Duration (S. Ide)

Development of advanced tokamak(N. Sakamoto) Conﬁnement improvement at high density (H. Takenaga) AMTEX (K. Tsuzuki)

Subject Core Plasma (T. Takizuka) H-mode Physics/ Pedestal (Prof. K. Toi(NIFS)) centralized joint research devices centralized joint research devices Modeling of ITB (Prof. A. Fukuyama(Kyoto U))

Current Hole (T. Fujita) 200 Number of collaborator MHD/Energetic Particle / Disruption, (M. Takechi) Current Drive (Prof. K. Hanada(Kyushu U)) 150 Divertor/SOL (N.Asakura) 100 Advanced Fueling (H. Ogawa)

50 Innovative operation (Prof. Y. Takase(U. of Tokyo)) Plasma Material Interaction (Prof. T. Tanabe(Nagoya U)) 0 1999 2000 2001 2002 2003 2004 3. Organization of Fusion Research in JAERI

Board of Executiv e Directors President : T. Okazaki Vice President : S. Tanak, O. Tanaka Executiv e Director : S. Matsuda

Office of Planning Office of ITER Project Promotion Director : S. Okada NAKA FUSION RESEARCH ESTABLISHMENT Director : Y. Okumura General Manager : S. Ishida Director General : M. Seki

DEPARTMENT OF FUSION DEPARTMENT OF FUSION DEPARTMENT OF FUSION DEPARTMENT OF ITER Project DEPARTMENT OF ADM.SERVICES PLASMA RESEARCH FACILITIES ENGINEERING RESEARCH Director : H. Ninomiya Director : M. Kuriyama Director : S. Seki Director : T. Tsunematsu Director : I. Kikuchi Deputy director : M. Kikuchi Deputy director : N. Hosogane Deputy director : H. Takatsu Deputy director : R. Yoshino Deputy director : H. Kobayashi

Administrative Service Div. Blanket Engineering Lab. Tokamak Program Division JT-60 Administration Div. Project Management Div. Head : M. Akiba General Manager.: Y. Miura G. M. : Y. Terakado Head : M. Mori Accounts Div.

Plasma Analysis Division JT-60 Facilities Div. 1 Superconducting International Utilities and Maintenance Div. G. M.: T. Ozeki G. M. : K. Kurihara Magnet Laboratory Coordination Div. Head : K. Okuno Head : T. Ando Safety Div. Large Tokamak Experiment JT-60 Facilities Div. 2 Plasma Heating Lab. Tokamak Device Div. and Diagnostics Division G. M. : N. Miya Head : K. Sakamoto G.M. : Y. Kamada Head : K. Shibanuma

RF Facilities Div. Tritium Engineering Lab. G. M. : T. Fujii Plant System Div. Plasma Theory Laboratory Head : M. Nishi Head : T. Shoji Head : Y. Kishimoto* *: Kyoto U. NBI Facilities Div. Office of Fusion Material G. M. : T. Yamamoto Research Promotion Safety Design Div. Experimental Plasma Head : M. Sugimoto Head : E. Tada Physics Laboratory Head : Y. Kusama JFT-2M Facilities Div. G. M. : T. Yamamoto Fusion Neutronics Laboratory Head : T. Nishitani Reactor System Laboratory Head : K. Tobita Introduction JT-60U ITER Physics R&D Objectives Advanced Tokamak Concepts for ITER & DEMO Performance

ITER DEMO Reactor

NCT JT-60U 4. Status of JT-60U Recent trends of operation cycles

FY2000 : 9 cycles two shifts 18 weeks of experiment FY2001 : 6 cycles two shifts 12 weeks of experiment FY2002 : 2 cycles two shifts 04 weeks of experiment FY2003 : 2 cycles one shift 08 weeks of experiment MG trouble in Feb. 2004 3 EX weeks cancelled. FY2004 : 2 cycles one shift 08 weeks of experiment 65s with reduced Bt capability FY2005 : 2 cycles one shift 08 weeks of experiment 65s

Research plans are based on two year frame. FY 2002 FY 2003 FY 2003 FY 2004

Planned

Electricity demand 40MW

FY 2002 FY 2003 MG trouble FY 2004 FY 2005 Present

Electricity demand 40MW 35MW 1. Modification for long pulse discharge

Max. pulse length of a discharge : 15s  65s. Modification on control systems in operation, Heating/CD and diagnostics, but not on major hardware.

Pulse length 15s 65s 4

(T) B flat top

t0 0

t 3

B 2 4Tx8s  1 ~2.7Tx65s 0 0 20 time 40 60 80  Control of NB: 30s, co(s)ntrol of RF: 60s.  PFC temperature is not actively cooled; carbon tiles (CFC for divertor), a small number of W tiles, and RF antennas.  Vessel temperature is kept 150-300 degC; mostly 150 degC in 2003-04 campaign. Improvement in NB systems (P-NB, N-NB)

CTR Positive-ion NB (P-NB)(~85keV) 4 tangential (2 co + 2 ctr): 30 s 7 perpendicular: 10s(6u),15 s(1u) Negative-ion NB (N-NB)(~360keV) 2(1) co-tangential: 10 s (30s)

N-NB CO ~2 MW/unit for long pulse operation. 350 MJ achieved with P-NB + N-NB ) u 400 40 2 W ( 2 M W 1 W 300 30 M M 0 4 2 200 20 u) (1 W -2002 M 100 10 5 P-NB 2003-04 1. N-NB 0 0 0 5 10 15 20 25 30 35 0 5 10 15 20 25 30 35 duration [s] duration [s] 65 s discharge has been achieved

E43173, Bt = 2 T Ip flat-top with divertor for ~60 s 10 Ip 0.5 15 s P-NB PNB N-NB 5 [MA] discharge 0 0 [MW] 2 2 n PEC e 1 1 19 -3 [MW] [10 m ] 0 0 1 Vloop 0.5 [V] 0 IFcoil 50 transformer 0 [kA] -50 current 0 10 20 30 40 50 60 70 time [s]

 Flux swing of transformer saved by NB+EC heating and EC breakdown assist.

 Long pulse LHCD will result in higher Ip.  For 30 s, 1.4 MA ELMy H-mode was maintained. Long sustainment of high βN in extended pulse operation

4 ITER N b

3 .

d Advanced Op e n i 2 Inductive Op. a t

s 1 u b =2.5x16.5s b = 2.3x22.3s s N N -2002 0 0 5 10 15 20 25 30 2003-04 sustained duration (s)

βN=2.3 sustained for 22.3s(~13.1τR) E44092, Bt = 1.56 T 1 15 I P p 10 NB (MA) 0.5 P-NB (MW) N-NB 5 q95~3.1-3.2 0 0 2 b =2.3 T H ~1.9 β N T T e,i 89PL N e i 5 (keV) 0 0 n /1019 2 e Da (m-3) 1 (a.u.) 0 0 5 10 15 20 25 30 time (s) 2 τR≡m0<σNC>a /12 D.R. Mikkelsen, Phys. Fluids B 1 (1989) 333. Long sustainment of high fBS

 Strong linkage of jBS(r), jtotal(r) and transport in high fBS plasmas, t t ITB n τE BS transport n e e r r e r r u strong current (ITB) r u s u c s

weak c e

S l r a B p current t o 0 r 1 0 r 1 t 0 r 1 profile τR

 Previously, fBS~80% was maintained for 2.7 s (~0.6τR)

 Control must be demonstrated in longer sustainment (>>τR). When ITB (c) changes=> p and jBS changes in τE. But jtot changes in τR. βp~2.25, HHy2~1.7 sustained for ~7.4s (~2.7τR) under nearly full CD in RS plasma

Reversed shear ELMy H-mode (3.4T, 0.8MA, q95~8.6, δ~0.42) inj Non-inductive CD: Bootstrap dominant & PNB (co)=3.2MW ~7.4 s (~16 , ~2.7 ) E43046 !E !R Duration 1 20 Ip PNB limited by 0.5 (MA) 10(MW) NB injection. 0 0 2 , βN~1.7, βp~2.25 !p !N 1 ! !N p 0 by FB control Vloop 1 0 (V) -1 nearly full CD 4 H89 2 H89~3, HHy2~1.7 4 P rad 2 No strong (MW) 0 impurity div 3 accumulation D! 2 1 Zeff: constant (~3) (a.u.) 0 4 6 8 10 12 Time (sec) fBS~75% sustained for ~7.4s (~2.7τR) 10 BS current peaked at the ITB. 8 T fBS~75%, fBD~20%, fCD~95% 6 i 6.3s well-aligned BS current (keV) 4 10.8s j(r) and p(r) reached 2 12.4s 0 stationary conditions. 12 E43046 I 5.1s 1 p 10 q 6.3s ]

A 8 10.8s fBS=75% M 0.5 [ 12.4s IBS 7.4 s 6 0 4 4 6 8 10 12 time [s] 2 0.8 8 1.2 cal cal jBS +jBD ] 1 2

0.6 6 m ! / 0.8 mea bootstrap

qmin A jtot

M 0.6 q [ current 0.4 min 4 j 0.4 cal 0.2 jBD 0.2 2 0 4 5 6 7 8 9 10 11 12 0 0.2 0.4 0.6 0.8 1 time [s] r/a Long sustainment of nearly full CD plasmas

Achieved region of ~ full CD with large fBS has been significantly extended. j(r) approached stationary conditions. Controllability of j(r) and p(r) must be studied in a long time scale. 100 2000 2004 NEW f >90% 80 1996 CD SSTR 60 >2τ f >90% R ITER CD (%) ρ*~0.006 Steady BS f 40 1998 ν*~0.06 State WeakHigh shear! H 2002 p 20 1998 1998 Rev.RS shear Double symbol: 0 0 2 4 6 8 10 ~Full CD Duration (sec) Divertor heat load is reduced by a factor of 10 during grassy ELM than during type I ELM

Grassy ELM type I ELM ΔWELM is reduced by a factor of 10 during grassy ELM. Narrower radial extent. Low ne* region (ne* ≤0.15).

q95~6.1 d~0.46 type I ELM type I ELM

Grassy ELM Grassy ELM Inter-machine comparison between C-Mod EDA and JFT-2M HRS regimes JFT-2M has found a “High Recycling Steady” (HRS) H-mode These features are qualitatively similar to C-Mod EDA regime ITPA Inter-machine collaboration was proposed (PEP-12). Questions: Is this the same regime as EDA? If so, how do access conditions and ﬂuctuations scale and compare?

C-Mod JFT-2M

EDA HRS National Centralized Tokamak Program

• Objectives: to realize high-beta steady-state operation with the use of reduced radio-activation ferritic steel in a collision-less regime. • Planning : For further progress in the high beta steady state research, the modiﬁcation of JT-60 is regarded as “National centralized tokamak facility program”. Detailed design work is ongoing in collaboration with universities, institutes and industries in Japan.

5 National Centralized Tokamak DEMO Facility Program reactors 4 Ideal no wall limit

N 3 ITER ! (Steady) (Q=5) 2 Target for long pulse exp. in JT-60U ITER 1 JT-60U (Inductive) JFT-2M (Q>10)

0 0 10 20 30 100 400 3000 TIME (s) Summary

• Long pulse operation is successfully performed. – 65 second discharge – 30 second H-mode – 24 second sustainment of βN~1.9 • Region of sustained high beta has been extended. – Stationary RS ELMy H-mode plasma with fBS~75% has been sustained for 7.4s under near full CD • NCT is being promoted. - DOE-JAERI technical planning of tokamak experiments(WS) • US-Japan cooperation is always productive. - C-MOD/JT-60U joint experiments