ARIES-ACT1 preliminary plasma description

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ARIES-ACT1 preliminary plasma description C. Kessel, PPPL ARIES Project Meeting, October 13, 2011

description

ARIES-ACT1 preliminary plasma description. C. Kessel, PPPL ARIES Project Meeting, October 13, 2011. Systems configuration to detailed configuration (JSOLVER equilibrium). Free-boundary equilibrium. control point. Converging on profiles between free and fixed boundary equilibria - PowerPoint PPT Presentation

Transcript of ARIES-ACT1 preliminary plasma description

Page 1: ARIES-ACT1 preliminary plasma description

ARIES-ACT1 preliminary plasma description

C. Kessel, PPPL

ARIES Project Meeting, October 13, 2011

Page 2: ARIES-ACT1 preliminary plasma description

Systems configuration to detailed configuration (JSOLVER equilibrium)

Systems Detailed ARIES-AT

R, m 5.5 5.5 5.2

IP, MA 10.6 10.0 12.8

βN 4.5 4.83 5.45

BT, T 5.5 5.5 5.86

n/nGr 0.95 0.87 1.0

n(0)/<n>v 1.3 1.37 1.35

T(0), keV 26.8 26.4 31.2

<T>v, keV 16.6 15.9 15.9

IBS, MA 9.54 8.35 11.65

ICD, MA (on,off-axis)

1.06 1.3 (0.38, 0.95) 1.28

Page 3: ARIES-ACT1 preliminary plasma description

Free-boundary equilibriumConverging on profiles between free and fixed boundary equilibria

If other other values of δ, ςo,I are found to be good for stability we can modify

Using coil set like ARIES-AT, will optimize coil locations later

κx = 2.21δx = 0.77ςo,I = 0li(1) = 0.54βN = 4.77q95 = 3.53

control point

Page 4: ARIES-ACT1 preliminary plasma description

Fixed boundary equilibria, preliminary operating point

Mismatch of inner flux surfaces is from profile differences

total jtoroidal

self-driven jtoroidal

Alignment of boundaries is very good.

Page 5: ARIES-ACT1 preliminary plasma description

Fixed boundary equilibria, preliminary operating point, cont’d

Pedestal in pressure, T, n

bootstrap currentIC or EC on-axis currentLH off-axis current

n = ne+Σni

Ip = 10 MAκ = 2.15δ = 0.7ςo,I = 0q(0) = 3.25qmin = 2.3βN = 4.83Li(1) = 0.49

p(0)/<p> = 2.06T(0)/<T> = 1.66n(0)/<n> = 1.37ne(0) = 1.97x1020

Pped ~ 175 kPa, approximately what we expect from EPED

Te = Ti

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Ideal MHD stability of high-n ballooning and external kink modes

Ballooning unstable on 4 out of 200 surface, all outside pedestal locationWeak instabilities, high critical-n number, should use EPED stability analysis for this region

External kink modes (using conformal wall, unstable with no conducting wall)

Mode number b/a to stabilize (real distance from plasma surface)

n = 1 0.46 (0.633 m)

n = 2 0.45 (0.619 m)

n = 3 0.425 (0.584 m)

Will pursue higher mode numbers, n=4-6, to determine most limiting

Page 7: ARIES-ACT1 preliminary plasma description

Further work• Examine stability with and without off-axis CD, profile adjustments to

accommodate transport or better stability– Check stability convergence

• Converge free-and fixed boundary equilibria, include different shaping if necessary

• Develop consistent heating and CD, time-dependent scenario– Converge PPPL and GA results

• Examine plasmas at higher βN, similar to ARIES-AT, limited by b/a(kink) ~ 0.33, compare with what we are choosing

– We have backed away from the highest βN values since experiments don’t appear to access these plasmas…..so what would the right parameters be?

– Should the wall be placed at 0.33, with lower βN, providing a % toward the with wall limit?– Based on what experimentalists observe, what would they project for βN, βN/βN

wall, q95, etc.

• Examine ACT2 candidates