ARIES ACT1 progress & ACT2

Transcription

1 ARIES ACT1 progress & ACT2 C. Kessel and F. Poli Princeton Plasma Physics Laboratory ARIES Project Meeting, 9/26-27/2012 Wash. DC

2 Outline Temperature and density profile variations at R = 5.5 m in order to see impact on q profile and MHD stability T profile, non-itb n profile T profile ITB H/CD analysis for R = 5.5 m LH ICRF EC NEW ACT1 equilibrium at R = 6.25 m Systems analysis of ACT2, conservative physics/dcll

3 Temperature and density profile variations Variation in T peaking Density profile same in all ese cases Non-ITB profiles Most peaked Most broad

4 T and n profile variations, density modification Density gradient spread out over e profile, using medium peakedness T Medium peaked T profile

5 T and n profile variations, ITB profiles Work in progress An attempt at an ITB configuration, same density profile as shown wi temperature peaking scan Very strong reversed shear Use more FWCD to control q(0) i e i He e

6 Lower Hybrid Heating and Current Drive Using 5 GHz for Lower Hybrid, and LSC code n + = , n - = 4.0 P + = 87%, P - = 13% (provides 1.6x I CD found between LSC and GENRAY/CQL3D) Typical launching location is ~ midplane Launching above midplane can provide slightly better A/W over broader n LHCD 60 o 45 o 32 o 0 o -45 o Allows for improved T breeding by getting launcher off e midplane Below midplane gives lower A/W and narrower n range

7 Ion Cyclotron Heating and Current Drive Use TORIC full wave analysis Examine 85, 90 and 95 MHz (chosen to avoid ion resonance at plasma center, to provide for FWCD) Deuterium 2 nd harmonic closest ion resonance 85 MHz 90MHz 95MHz Thermal ions Thermal electrons F. Poli, PPPL Find 5 MW drives ~ ka *more an we had assumed, so we can drop ICRF power in flattop to 5-10 MW from 15 MW Early e ion resonance absorbs some energy, but later e R mag shifts out and Te rises, en electrons absorb all e energy A good startup Up to 15 MW of ICRF power I ICRF I (MW) (MA) reference 90MHz 85MHz 95MHz 5 MW time (s)

8 Electron Cyclotron Heating and Current Drive Using GENRAY ray-tracing % &"! poloidal projection z=60 cm θ=95 An EC frequency of 170 GHz (same as ITER) Outboard midplane launchers at Z = +0.6, 0.0, and -0.6 m Trajectories are refracted out of plasma for φ>48-50 o! " # $ )*+,-.*+,- (!'!&!%!!!" toroidal projection,()*+ &!&"!!%!!"! # #"! $ '()*+ Set poloidal angles of 3 launchers, scan toroidal angles from 20 o to 50 o determine current drive efficiency z=0 cm θ=90 z=-60 cm θ=85 F. Poli, PPPL

9 25 EC, cont d 0.8 F. Poli, PPPL CD efficiency (A/kW) sqrt (norm. tor. flux) azimual angle (deg) All launchers have largest CD efficiency for φ~34-42 deg Can EC replace on-axis CD of ICRF? FW gives ~ 50 A/kW Can we use EC to manipulate q profile? EC looks promising CD efficiency (A/kW) azimual angle (deg) broad range of radii, ρ= z=+60cm 5 z= 0cm z=-60cm sqrt (norm. tor. flux)

10 New ACT1 Plasma Equilibrium ACT1-old, R = 5.5 m ACT1, R = 6.25 m Lower triangularity to obtain less horizontal inboard and less vertical outboard flux lines

11 Systems Analysis of ACT2 ACT2 is conservative physics N total < 3.25 H 98 < 1.3 n/n Gr < 1.0 = 2.0 or 2.2? Inboard DCLL blanket (Laila) SOL = 0.10 m FW/Blkt = 0.75 m Skel = 0.25 m gap = 0.02 m VV = 0.33 m gap = 0.06 m q div,peak OB <?? B T,max <?? = (1.5<N w > x 1.25q FW,ave 0.3) P pump = 0.04 x P fusion, pump = 0.9 P subs = 0.04 x P elec,gross aux = 0.4 Used different j SC vs B T,max since I was exceeding 18 T at e coil in some cases Scanned B T = T N = q 95 = n/n Gr = Q = = R = m f Ar =

12 This operating point is a bugger! 975 < P elec (MW) < 1025 Filter set #1 N total ( N + N fast ) < 3.25 q div,peak OB < 15.0 MW/m 2 Note large radius Note large toroidal field Note low N Too high n/n Gr Too high H 98 R B T I p β N q 95 n G Q H 98 P aux f BS B Tc q div Nw Z eff

13 This operating point is a bugger!, cont d Filter set #2 975 < P elec (MW) < 1025 N total ( N + N fast ) < 3.25 H 98 < 1.3 does not do any filtering n/n Gr < 1.1 R B T I p β N q 95 n G Q H 98 P aux f BS B Tc q div Nw Z eff q div,peak OB < 20 MW/m 2 and n/n Gr < 1.2, turn H 98 filter off

14 This operating point is a bugger!, cont d Filter set #3 continue to box in a solution set, relax desired n/n Gr value N total ( N + N fast ) < 3.25 H 98 < 1.3 n/n Gr < 1.3 q div,peak OB < 17.5 MW/m < P elec (MW) < 1025 R B T I p β N q 95 n G Q H 98 P aux f BS B Tc q div Nw Z eff Scanned aspect ratio to 3.0 and 5.0, and found same results

15 Lower P elec, in order to get viable solution range We are stuck between needing high P fus to cover recirculating power and ermal conversion, so we need high density But we are trying to keep e Ip low (or q 95 high) in order to reduce e CD part of recirculating power 750 MWe R B T I p β N q 95 n G Q H 98 P aux f BS B Tc q div Nw Z eff

16 Lower P elec, in order to get viable solution range Try 500 MWe R B T I p β N q 95 n G Q H 98 P aux f BS B Tc q div Nw Z eff

17 Physics Have generated EQDSK for ACT1 at 6.25 m All physics analysis has still been done at 5.5 m case Need to update TSC simulations to 6.25 m Need to update H/CD analysis to 6.25 m Ideal MHD for 6.25 m cases Complete disruption simulation, at 5.5 m or change to 6.25 m? PF Coil solution for 6.25 m Begin to pursue ACT2 physics, expect e ACT1 physics/systems comparison to be valid here

18 Systems for ACT2 This operating point is at LARGE radius It is difficult to get wiin desired physics parameters and divertor heat flux simultaneously, at 1000 MWe Lowering P elec helped, but e COE may suffer Battle between large P fus and low recirculating CD power, requiring high n, but low Ip Plasma elongation ALWAYS was at higher value, so may not be able to adopt 2.0 for conservative case W shells in outboard blanket Low N drives us to higher B T, high CD power,..

19 Changes to systems code at degrade solutions Power scrape-off wid correction good systems trade-off study Lower recirculating efficiency for H/CD sources Oer recirculating powers Lower CD efficiency in plasma Lower ermal conversion efficiency for DCLL compared to SiC Inboard radial build increase for DCLL compared to SiC N total = N + N fast