Pedestal Particle Transport Study using Perturbation Method in … WG(B)/US-TTF... ·...

Pedestal Particle Transport Study using Perturbation Method in HL-2A and KSTAR

W.W. Xiao1,2,3, P.H. Diamond3,4, W.L. Zhong2, S.W. Yoon1, Z.B. Shi2, X.Y. Han2, L. Wang3, X.L. Zou5, W.C. Kim1, K.J. Zhao2,3, M. Xu4, J. Cheng2, J.Q. Dong2,6, X.T. Ding2, J.G. Bak1, Y.U. Nam1, H.K. Kim1, H.T. Kim1, K. P. Kim1, C.Y. Chen2, B.B. Feng2, L.H. Yao2, J. I. Song1, S.G. Lee1, T. Rhee3, J.M. Kwon3, X.L. Huang2, Y.G. Li2, D.L. Yu2, K.D. Lee1, S.I. Park1, M. Jung1, Y.S. Bae1, Y.K. Oh1, L.W. Yan2 HL-2A team and KSTAR team 1) National Fusion Research Institute , Daejeon, Korea 2) Southwestern Institute of Physics, P.O. Box 432, Chengdu, China 3) WCI Center for Fusion Theory, National Fusion Research Institute, Daejeon, Korea 4) UCSD, 9500 Gilman Drive, La Jolla, California 92093, USA 5) CEA, IRFM, F-13108 Saint-Paul-lez-Durance, France 6) Institute for Fusion Theory and Simulation, Zhejiang University, Hangzhou, China

US Transport Task Force Workshop, April 10-13, 2012, Annapolis, MD W.W. Xiao, et al,

Outline

• Motivation • Experimental results in HL-2A and in KSTAR - Edge density profile - Particle source location - Perturbation experiments ELM mitigation by SMBI - Edge particle flux spectrum • Comparison of transport study - Comparisons with/without SMBI - Particle flux analysis - Toroidal rotation analysis - Energy transport analysis • Summary


Motivation


Current Pressure Pedestal width Pedestal height Recycling ……

Transport –Particle –Energy –Momentum ……

Many physical topics …. We try to understand procedures ….

H-mode Stability operation ELM physics …

This talk will focus on particle transport with and without SMBI to mitigate ELMs.

4

Experiments in HL-2A and KSTAR

Edge density profile and pedestal construction in pedestal in concept and experiment.


500 600 700 8000

0.5

1.0

1.5

time(ms)

P(M

W)

0

1

2

3

D

(a.u

.)

NBI

ECRH

0.25 0.3 0.35 0.40

0.5

1

1.5

2

r(m)

ne

(

10

19m

-3)

HL-2A #19425

851ms

814 ms

796ms

time(ms)

R(m

)

400 500 600 700 800 900

1.7

1.8

1.9 2

4

6

8

x 104

SBMI

HL-2A #19425

V(m/s)

~1.31019m-3

Wped

~3.3cm

Experiments in HL-2A

Particle source


Ohmic discharge H-mode discharge

W.W. Xiao, RSI 2010

NFRI, WCI, W.W. Xiao, et al., 2012/4/19

1Phase of the density perturbation 2 Peak of Ha intensity 3Density increase ratio 4 Temperature decrease

HL-2A #3875

Experiments in HL-2A and KSTAR


Store energy in ELM mitigation by SMBI in HL-2A and KSTAR

2.4 2.6 2.8 3 3.2 3.40

200

400

Sto

re-E

(kJ)

2.4 2.6 2.8 3 3.2 3.40

0.5

I p(M

A)

2.4 2.6 2.8 3 3.2 3.40

5

nl(

10

19m

-3)

0

5

10

Ha

(a.u

.)

2.4 2.6 2.8 3 3.2 3.40

5

time(s)

SM

BI

KSTAR #6353

4

6

810

12

Da

(a.u

.)

2.5 3 3.50

5

SM

BI

2.5 3 3.5100

200

300

400

time(s)

Sto

re-E

(kJ)

SMBI(6ms) SMBI(8ms)

fELM-SMBI

~62HzfELM

~28Hz Jogging

KSTAR #6352

I ~500ms

800 8200

1

2

3

time(ms)

Ha

(a.u

.)

2

4

6

8

SM

BI(

a.u

.)

780 800 820 84024

26

28

30

time(ms)

(m

s) 800 8200

1

2

3

Ha

(a.u

.)

2

SM

BI

780 800 820 84010

20

30

time(ms)

E(m

s)

HL-2A

15886

HL-2A 15886

HL-2A 15886

These observations mean that the pedestal particle confinement is degraded by SMBI injection. Point: SMBI deposition in the pedestal inhibits the formation of extended transport events which span the full width of the pedestal. This comes at the expense of an increase in the population of smaller fluctuations and avalanches.

[I. Gruzinov, P. H. Diamond and M. N. Rosenbluth, PRL, 2002]


Particle transport

650 655 660 665 6700

0.5

1

1.5

time(ms)

D

(a.u

.)

720 725 730 735

time(ms)

650 670 690 710 730 7500

0.5

1

1.5

time(ms)

D

(a.u

.)

5

SM

BI

10-1

100

101

102

101

102

103

104

105

f(kHz)

pa

rtic

le flu

x(a

.u)

650-670ms

715-735ms

Hl-2A# 16246

I

A B

A

B

(b)

(c)

(a)

A,without SMBI B, with SMBI

I. Gruzinov, P. H. Diamond and M. N. Rosenbluth, PRL, 2002 T. Rhee, J.M. KwonH. Diamond, W.W. Xiao., PoP, 2012 W.W. Xiao, P.H. Diamond, X.L. Zou, et al., NF, 2012

1.3 1.4 1.5 1.60

2

4

6

8

10

12

R(m)

Jsa

t

w/o SMBI

W/ SMBI

0.1 10 10010

-1

100

101

102

frequency(kHz)

A(a

.u.)

w/o SMBI

w/ SMBI

(b)

KSTAR #6352

(a) (b)

Outer Divertor

Particle flux analysis

Key point SMBI deposition in the pedestal inhibits the formation of extended transport events

0.1 10 10010

-1

100

101

102

f(kHz)

A(a

.u.)

w/o SMBI

w/ SMBI

100

101

102

10-2

f(kHz)

Pa

rtic

le flu

x(a

.u.)

w/o SMBI

w/ SMBI

HL-2A #16128

KSTAR #6352

(a) divertor

mid-plane

J. G. Bak et al., Contrib. PP 2010

J. Cheng PPCF, 2010

Particle transport

500 600 700 8000

0.5

1.0

1.5

time(ms)

P(M

W)

0

1

2

3

D

(a.u

.)

NBI

ECRH

0.25 0.3 0.35 0.40

0.5

1

1.5

2

r(m)

ne

(

10

19m

-3)

HL-2A #19425

851ms

814 ms

796ms

time(ms)

R(m

)

400 500 600 700 800 900

1.7

1.8

1.9 2

4

6

8

x 104

SBMI

HL-2A #19425

V(m/s)

~1.31019m-3

Wped

~3.3cm


Particle flux analysis

Issues: How to remove the influence from ELM burst and the extra particle source?

1

1.5

2

ne(1

019m

-3)

800 900 1000 1100 1200

0.6

1

1.4

time(ms)

Te(k

eV)

29.3

24.0

18.7

13.7

9

~ 0.22X1019

m-3

(a)

(b)

1

1.5

2

ne(1

019m

-3)

800 900 1000 1100 1200

0.6

1

1.4

time(ms)

Te(k

eV)

29.3

24.0

18.7

13.7

9

~ 0.22X1019

m-3

(a)

(b)

HL-2A #3875

3

3.2

3.4

3.6

A(a

.u.)

32 34 36 38

0.4

0.45

0.5

0.55

r(cm)

Ph

ase

(ra

d.)

32 33 34 35 36 37 38

10

0

-10

-20

r(cm)

Vco

n(m

/s)

0

1

2

3

D(m

2/s

)

sim.

exp.

sim.

exp.

(b)

(a)

pedestal top

HL-2A #14045HL-2A #14045

W.W. Xiao, RSI 2010 S. P. Eury, PoP 2005 W.W. Xiao, PRL 2010

? L. Wang and P.H. Diamond, NF, 2011

Momentum transport

500 600 700 8000

0.5

1.0

1.5

time(ms)

P(M

W)

0

1

2

3

D

(a.u

.)

NBI

ECRH

0.25 0.3 0.35 0.40

0.5

1

1.5

2

r(m)

ne

(

10

19m

-3)

HL-2A #19425

851ms

814 ms

796ms

time(ms)

R(m

)

400 500 600 700 800 900

1.7

1.8

1.9 2

4

6

8

x 104

~1.31019m-3

SBMI

HL-2A #19425

Wped

~2.6cmV(m/s)

time(ms)

R(m

)

400 500 600 700 800

1.65

1.7

1.75

1.8

1.85

1.9

1.95

400 500 600 700 800 9000

20

40

60

80

100

time(ms)

V(k

m/s

)

R=1.65m, core

R=1.93m, edge

1.6 1.7 1.8 1.9 220

40

60

80

100

R(m)

V(k

m/s

)

710ms w/o SMBI

750ms w/ SMBI

790ms w/o SMBI

2

4

6

8

x 104

time(ms)

R(m

)

400 500 600 700 800 900

1.7

1.8

1.9 2

4

6

8

x 104

HL-2A #19425

HL-2A #19425

HL-2A #19425


Toroidal rotation analysis

Poloidal rotation analysis is ongoing…

Energy transport


Energy transport analysis

Modulation ECRH heating in pedestal region

e

Summary

• ELM mitigation by SMBI appears successful and some promising results have been obtained on HL-2A and KSTAR.

- How to understand the physics of the ELM mitigation?

- Global plasma confinement is small changed during SMBI.

- Plasma rotation was modulated during SMBI.

• Long time ELM mitigation has been obtained by multi-SMBI pulses, ~ 400ms. More than confinement time.

• How to remove the influence from ELM burst and the extra particle source?

• Balance transport analysis is necessary and to understand the complex edge transport explore the relation of particle, energy and momentum.


Pedestal Particle Transport Study using Perturbation Method in … WG(B)/US-TTF... ·...

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