ARIES-ACT1 preliminary plasma descriptionC. Kessel, PPPL

ARIES Project Meeting, October 13, 2011

Systems configuration to detailed configuration (JSOLVER equilibrium)

Systems DetailedARIES-ATR, m5.55.55.2IP, MA10.610.012.8N4.54.835.45BT, T5.55.55.86n/nGr0.950.871.0n(0)/v1.31.371.35T(0), keV26.826.431.2v, keV16.615.915.9IBS, MA9.548.3511.65ICD, MA (on,off-axis)1.061.3 (0.38, 0.95)1.28

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

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

Using coil set like ARIES-AT, will optimize coil locations laterx = 2.21x = 0.77o,I = 0li(1) = 0.54N = 4.77q95 = 3.53control point

Fixed boundary equilibria, preliminary operating pointMismatch of inner flux surfaces is from profile differencestotal jtoroidalself-driven jtoroidalAlignment of boundaries is very good.

Fixed boundary equilibria, preliminary operating point, contdPedestal in pressure, T, nbootstrap currentIC or EC on-axis currentLH off-axis currentn = ne+niIp = 10 MA = 2.15 = 0.7o,I = 0q(0) = 3.25qmin = 2.3N = 4.83Li(1) = 0.49p(0)/ = 2.06T(0)/ = 1.66n(0)/ = 1.37ne(0) = 1.97x1020Pped ~ 175 kPa, approximately what we expect from EPEDTe = Ti

Ideal MHD stability of high-n ballooning and external kink modesBallooning 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)Will pursue higher mode numbers, n=4-6, to determine most limiting

Mode numberb/a to stabilize (real distance from plasma surface)n = 10.46 (0.633 m)n = 20.45 (0.619 m)n = 30.425 (0.584 m)

Further workExamine stability with and without off-axis CD, profile adjustments to accommodate transport or better stabilityCheck stability convergence

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

Develop consistent heating and CD, time-dependent scenarioConverge PPPL and GA results

Examine plasmas at higher N, similar to ARIES-AT, limited by b/a(kink) ~ 0.33, compare with what we are choosingWe have backed away from the highest N values since experiments dont appear to access these plasmas..so what would the right parameters be?Should the wall be placed at 0.33, with lower N, providing a % toward the with wall limit?Based on what experimentalists observe, what would they project for N, N/Nwall, q95, etc.

Examine ACT2 candidates