TOTAL Simulation of

ITER Plasmas

Kozo YAMAZAKI

Nagoya Univ., Chikusa-ku, Nagoya 464-8603, Japan

1

OUTLINE

1. Introduction

2. TOTAL Transport Benchmark

3. Pellet Injection and ITB

Formation

4. Impurity Injection and Edge

Control

5. NTM Evolution and ECCD

Stabilization

6. Summary

2

● Start (~1980)● Tokamak (2nd stability) 2D+1D 　 K.Yamazaki et al., Nuclear Fusion Vol.25 (1985) 1543.

● Helical Analysis 3D+1D K.Yamazaki et al., Nuclear Fusion Vol.32 (1992) 633.

● Burning Simulation (Tokamak & Helical) K.Yamazaki et al., Nuclear Fusion Vol.49 (2009) 055017.

Based on JT-60U ITB operation and LHD e-ITB data.

3

History of TOTAL code

Toroidal Transport Analysis Linkage

1. Introduction

Core PlasmaEquilibrium 　 Tokamak: 2D 　 APOLLO 　 　 　 　 　 　　　　　　 Helical: 3D 　 VMEC, DESCUR, NEWBOZ　Transport 　 Tokamak 　： TRANS , GLF23 , NCLASS　 　 　 　 　 　 　 　 Helical 　： HTRANS, 　 GIOTAStability 　 　 　 　 　 NTM, 　 Sawtooth, Ballooning mode

Impurity IMPDYN (rate equation) including Tungsten ADPAC 　（ various cross-section ）

Fueling NGS (neutral gas shielding) model 　　　　　　　　　　　　　　 mass relocation model (HFS)　　　　　　 NBI HFREYA, FIFPC Puffing AURORA Divertor 　 two-point divertor model, density feedback control

Edge transport H-mode edge model

World Integrated Modeling

TOTAL-T,-H(J)TOPICS(J)

TASK(J)CRONOS(EU)TRANSP(US)ASTRA(RU)

4

Toroidal Transport Analysis Linkage

Main Feature of “TOTAL” is to performboth Tokamak and Helical Analyses

Toroidal Transport Analysis Linkage

For Predictive Simulation and Experimental Data Analysis

TOTAL Code Development

NTM,Sawteeth Analyses

PelletInjectionGLF23

5

Ref:　C.E.　Kessel　et　al.,　Nucl.　Fusion　47　(2007)　1274–1284

TOTALTOTAL

TOTAL　code　　CDBM　model　　　　　　　　　　　　　　　　　　　　　　(GLF23　model)

2. TOTAL Transport

Benchmark

ITG

BEBohmGyroBohmanomalous F

21

ITG

BEITG

BEF

1

1

　◆　E×B　shearing　rate　:

RB

E

dr

d

B

RB rBE

◆　ITG　linear　growth　rate: qR

cs iiITG

2/13/2

dr

dq

q

rs

anomalousalneoclassicie ,

Bohm/GyroBohm Mixed Transport Model

Coefficients　are　determined　using　typical　experimental　data　of　JT-60U　ITB　data　and　LHD　e-ITB　operations.　

TALA,　T.,　et　al.,　Plasma　Phys.　Control.　Fusion　43　(2001)　507-523.

7

3. Pellet Injection and ITB

Formation

Transport model cheked by JT-60U data

Tungsten Transport without and with ITB

0

2 104

4 104

6 104

8 104

1 105

0 0.2 0.4 0.6 0.8 1

ITG

ExB

0

5 104

1 105

1.5 105

2 105

2.5 105

3 105

0 0.2 0.4 0.6 0.8 1

ITG

ExB

0

10

20

30

40

50

60

0 0.2 0.4 0.6 0.8 1

Ti

Te

ne

deposition

Tem

pe

ratu

re &

density [ke

v &

10

19 m

-3]

0

10

20

30

40

50

60

0 0.2 0.4 0.6 0.8 1

Ti

Te

ne

deposition

Tem

pe

ratu

re &

den

sity

[ke

v &

10

19 m

-3]

ITB

HFS Pellet Injectionwith ITB

LFS Pellet InjectionWithout ITB

ITB Formation by Pellet Injection

10

ITB formation in Helical Reactor

HR-1

0

2 105

4 105

6 105

8 105

0 0.2 0.4 0.6 0.8 1

facc3gamm

ExB

ITG

[1/s]

-400

-300

-200

-100

0

0

0.2

0.4

0.6

0.8

1

0 0.2 0.4 0.6 0.8 1

Er

[V/cm]

F(

ExB/

ITG)E

r

F

0

10

20

30

40

0 0.2 0.4 0.6 0.8 10

20

40

60

80

ne

Te

Ti

deposition

Ti, T

e

[keV]

ne

(1019/m3)

Ambipolar radial electric field can form ITB

11

[1]　M.E.　Puiatti.,　et　al.,　Plasma　Phys.　Control.　Fusion　44　(2002)　1863[2]　M.E.　puiatti.,　et　al.,　Plasma　Phys.　Control.　Fusion　45　(2003)　2011

ReferenceJET Experiment

0

0.5

1

1.5

2

2.5

3

0 0.2 0.4 0.6 0.8 1

Te [keV]

r/a

Te

0

5 1016

1 1017

1.5 1017

2 1017

2.5 1017

3 1017

3.5 1017

0 0.2 0.4 0.6 0.8 1

n Ar [m

-3]

r/a

18+

17+

16+

total

15+

nAr

0

0.05

0.1

0.15

0.2

0 0.2 0.4 0.6 0.8 1Power [MW/m3]

r/a

Pline

Pbrem

Prad

Prad

#52136

NBI 12MWArgon seeded ELMy H-mode discharge

Low triangularity

TOTAL code simulation with Sawteeth

12

4. Impurity Injection and Edge Control

2.42.73

3.3

0 2 4 6 8 10

n Ar17(0)[m

-3]

time [sec]

2.22.42.62.8

Te(0)[keV]

0.820.840.860.88

ne(0)[m-

3 ]0.6

0.8

1

q(0)

691215

Power[MW]

Prf

Prad

[sec]65.0~saw317

, /100.7 mn sAr

Simulation for a JET Sawtooth

13

ITER

Radial profile before (solid curve) and after (dashed curve) a sawtooth crash.

0

5

10

15

20

25

30

0 0.2 0.4 0.6 0.8 1

Te [keV]

r/a

Te

0

5 1014

1 1015

1.5 1015

0 0.2 0.4 0.6 0.8 1

n Ar[m-

3 ]

r/a

total18+

17+

16+

15+

nAr

0

0.02

0.04

0.06

0.08

0.1

0.12

0 0.2 0.4 0.6 0.8 1

Power [MW/m3]

r/a

Prad

Pline

Pbrem

Psyn

Prad

0

5 1014

1 1015

1.5 1015

2 1015

2.5 1015

3 1015

3.5 1015

4 1015

0 0.2 0.4 0.6 0.8 1n W [m-

3 ]r/a

68+

66+64+

62+

45+ 30+55+60+

total nw

0

0.02

0.04

0.06

0.08

0.1

0 0.2 0.4 0.6 0.8 1

Power [MW/m3]

r/a

Prad

PbremPsyn

Pline

Prad

0

0.2

0.4

0.6

0.8

1

1.2

0 0.2 0.4 0.6 0.8 1

n e [10

20m

-3]

r/a

ne

14

0

0.2

0.4

0.6

0.8

1

0 0.2 0.4 0.6 0.8 1

KrArNeHeNo injection

P rad [MW/m

3 ]

r/a

q=2 surface

0

50

100

150

He C O Ne Ar Fe Kr Mo

SynchrotronLineBremsstrahlung

Radiation power [MW]

Impurity species

%5 PPP

RFfus PP 10

LHsep PP

Maximum impurity concentration at the reference ITER inductive scenario

based on the ELMy H-mode regime

020406080100120140160

0 50 100

PalpPrfPradPsep

Power [MW]

time [sec]

00.10.20.30.40.5

0 2 4 6 8 10 12

totalcoremantle

Radiation fraction

nHe/ne [%]

00.20.40.60.81

0 0.005 0.01 0.015

totalcoremantle

Radiation fraction

nKr/ne [%]

Radiative Mantle Formation by Kr Injection in ITER

17

225

3

2

2

04

22

2

2

22

03

222

2

01

1

1,

2.0

111

)(

Wa

If

B

Lk

WL

Lgk

WWqL

Lk

WW

W

BjLk

Wk

ECEC

ps

qEC

p

qpipsispol

dsps

qpssGGJ

dpBSqBS

　

HFECpolGGJBSdt

dW

Model: Modified Rutherford EquationModel: Modified Rutherford Equation

cos)(2 2

W

W

r

m HF

sHF

42

||

4

||

)4

()( rd

bW

Resonant HF Non-resonant HF

Q.Yu et al., PRL 85(2000)2949

k1 1.0k2 10.0k3 1.0k4 1.0k5 5.0

5. NTM Evolution and ECCD Stabilization

0

5　105

1　106

1.5　106

0 0.2 0.4 0.6 0.8 1

j[A/m

2 ]

r/a

IBS　with　NTM(3-2)

IBS　with　NTM(2-1)

ITOTAL

ITER (Ip=15MA)

0

5

10

15

20

25

30

1

1.5

2

2.5

3

3.5

0 0.2 0.4 0.6 0.8 1

Te　　

[keV] q

no　NTM

3/2　mode

2/1　mode

3/2　+　2/1　mode

3/2　island

2/1　island

NTM analysis of an ITER Plasma without external helical field

0.05

0.1

0.15

0.2

0.25

30 35 40 45 50 55 60 65

W

time　[s]

60[kA]

80[kA]

100[kA]

120[kA]

ECCD

2/1　mode

0

0.05

0.1

0.15

0.2

0.25

30 35 40 45 50

w

time(s)

Δ α c=0.250.20

0.150.100.05

0.00

(b)

ECCD Stabilization against NTM In ITER Plasma

Application of External Helical Field

Old experiments on current carrying stellarator disruption-free (without BS current)

(1) Error Field Modification (BHF/B~10-4~-3) resonant field feedback (high frequency) resonant magnetic breaking (low frequency) (2) Helical Field-Assisted (BHF/B~10-2~-1) static non-resonant application mode locked ? disruption ?

(3) Tokamak-Stellarator Hybrid (BHF/B~1) static non-resonant application　　　　　　 disruption-free ?

20

Non-Resonant Helical Field Application

Br/B0~10-3Without　Helical　Field With　Helical　Field

21

Stabilized

GGJ

dW/dt

BS

6. Summary (1/2)

(1) 1.5-D tokamak code and 2.0-D helical code have been developed for predictive simulation and experimental analysis related to Transport and MHD effects.

(2) ITB can be formed by the deep penetration of HFS pellet injection in tokamaks. The shallow pellet penetration of low-field-side injection did not lead to the ITB formation in the present model.

(3) Sawtooth oscillation effects on ITER impurity transport has been carried out based on a JET simulation model, and 20% radiation reduction was suggested in ITER.

22

6. Summary (2/2)

(4) Low-z impurity, like He, cannot form radiative mantle, and causes large bremsstrahlung radiation loss in the core. About 84% (core:33% / mantle:51%) of input power is radiated inside the LCFS by Kr impurity seeding without inducing any deleterious change.

(4) NTM excitation and control have been simulated using modified Rutherford equation.　The　appearance　of　m=2/n=1　NTM　leads　to　the　20　%　reduction　in　the　central　temperature　in　ITER-like　reactors.　The　m/n=3/2　NTM　can　be　stabilized　by　non-resonant　helical　field.　

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