| Miniproposals | ||||||||||
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| Operators | |
| Session leader(s): | Spencer Pitcher |
| Physics operator(s): | Steve Wolfe,Robert Granetz |
| Engineering operator(s): | Gary Dekow |
| Engineering Operator Run Comment |
| MP #262 Effect of main chamber recycling on H-Mode confinement, SL: Pitc |
| Session Leader Plans |
| Physics Operators Plans |
| Session Leader Summaries |
| Entered: Jul 7 2004 03:49:23:290PM |
| Author: To Be Determined |
| MP 262 The Effect of Main Chamber Recycling on H-mode Confinement SL S Pitcher PO S Wolfe Today we did a left gap scan, 800 kA, nl04 = 1.0, 5.4 T, D antenna power ramps, right gap fixed at approx 20 mm, fixed Xpt geometry. The RF threshold power changed quite drastically from 0.7 MW at left gap of 26mm to 1.4 MW at 3 mm left gap. We tried to find the threshold power for 0.0 mm left gap by bringing in J antenna, but this was not successful. The problem here seemed to be J causing D to trip-out. Extrapolating our results, we predict an RF threshold at 0 mm left gap of around 1.8 MW, but this was beyond our capabilities today. The reduction of left gap from 26 mm to 3 mm was accompanied by the following changes (in the L-phase before the H-mode transition), (1) no change in divertor gas pressure (2) no change in outside midplane gas pressure (3) a large increase in etop gas pressure, factor 5 approx! (4) no change in divertor radiation (5) no change in the H-alpha at the inside midplane (6) a factor 4 decrease in lower inner wall H-alpha (partly includes inner divertor nose) (7) no change in Zeff (8) a factor 2 approx increase in 2pi radiation (9) a slight decrease in elongation from 1.69 to 1.62 (10) an increase in total power threshold from 1.6 MW to 2.2 MW We were concerned about the variation of elongation, so at the end of the day we confirmed (shot 26) that elongation was not playing a role in the change in threshold. The most interesting observation was the strong variation of the etop gas pressure, which increases when running close to the inner wall. The question is whether this change is due to neutrals generate at the inner wall finding their way up to the top of the machine, or whether we are doing something to the magnetic geometry in the far SOL to affect the pressure at etop. Previously, we have found that the secondary separatrix can influence the etop pressure. In all, a very interesting run. Thresholds are definitely influenced by the proximity of the inner wall to the plasma. Spencer Pitcher ------------------------------------------------------ The interesting shots in this run are listed below, with their corresponding threshold powers (including corrections for Pohmic and dW/dt) and transition times. IDL> print,shot 1000511004 1000511005 1000511006 1000511012 1000511013 1000511018 1000511019 1000511026 IDL> print,pthr1 (MW) 1.82045 1.93330 2.15194 2.15936 1.58443 1.77325 1.67874 1.68728 IDL> print,t2 (secs) 0.859000 0.896000 1.03700 1.02200 0.719000 1.06000 1.01500 0.917000 ------------------------------------------------------ Shot by shot details. **** shot 2 Kaiser helium gas on discharge disrupts early t = 0.3 s **** shot 3 no Kaiser gas rgap = 21 mm , lgap = 15 mm RF ratty jumps to H-mode at Prf = 0.8 MW **** shot 4 Kaiser helium gas on, 4 psi (230 Torr), duration 0.1 @ t = 0.4 s abandon E antenna, focus on D, put J late in shot lgap = 12 mm , rgap = 20 mm jumps to H-mode at 1.0 MW **** shot 5 Kaiser helium gas on, 4 psi (230 Torr), duration 0.1 @ t = 0.4 s abandon E antenna, focus on D, put J late in shot lgap = 12 mm , rgap = 24 mm >>> mistake jumps to H-mode at 1.1 MW **** shot 6 Kaiser helium gas on, 4 psi (230 Torr), duration 0.1 @ t = 0.4 s abandon E antenna, focus on D, put J late in shot lgap = 4 mm , rgap = 23 mm jumps to H-mode at 1.4 MW **** shot 7 Kaiser helium gas on, 4 psi (230 Torr), duration 0.1 @ t = 0.4 s abandon E antenna, focus on D, put J late in shot lgap = 0 mm , rgap = 23 mm no H-mode **** shot 8 Kaiser helium gas on, 4 psi (230 Torr), duration 0.1 @ t = 0.4 s D and J antennas......D faulted lgap = 0 mm , rgap = 23 mm no H-mode **** shot 9 Kaiser helium gas on, 4 psi (230 Torr), duration 0.1 @ t = 0.4 s D and J antennas......no D lgap = 0 mm , rgap = 23 mm no H-mode **** shot 10 Kaiser helium gas on, 4 psi (230 Torr), duration 0.1 @ t = 0.4 s D and J antennas......D faulted lgap = 0 mm , rgap = 23 mm no H-mode **** shot 11 Kaiser helium gas on, 4 psi (230 Torr), duration 0.1 @ t = 0.4 s D and J antennas......D faulted lgap = 0 mm , rgap = 23 mm no H-mode **** shot 12 Kaiser helium gas on, 4 psi (230 Torr), duration 0.1 @ t = 0.4 s go back to shot 6...D antenna only, J later lgap = 6 mm , rgap = 23 mm H-mode at Prf = 1.4 MW....good shot, good repeat of shot 6 **** shot 13 Kaiser helium gas on, 4 psi (230 Torr), duration 0.1 @ t = 0.4 s lgap = 20 mm , rgap = 20 mm H-mode at Prf = 0.79 MW ....big drop in threshold! Is this left gap or elongation? **** shot 14 Kaiser helium gas on, 4 psi (230 Torr), duration 0.1 @ t = 0.2 s no plasma...(Granetz took over from Wolfe) **** shot 15 Kaiser helium gas on, 4 psi (230 Torr), duration 0.1 @ t = 0.2 s stability problem, disrupt t = 0.57 s **** shot 16 Kaiser helium gas on, 4 psi (230 Torr), duration 0.1 @ t = 0.2 s stability problem, disrupt t = 0.55 s **** shot 17 Kaiser helium gas on, 4 psi (230 Torr), duration 0.1 @ t = 0.2 s stability problem, disrupt t = 0.54 s **** shot 18 Kaiser helium gas on, 4 psi (230 Torr), duration 0.1 @ t = 0.2 s push RF later lgap = 20 mm, rgap = 17 mm good plasma, approx repeat of shot 13 **** shot 19 Kaiser helium gas on, 4 psi (230 Torr), duration 0.1 @ t = 0.2 s lgap = 25 mm, rgap = 17 mm good plasma **** shot 20 Kaiser helium gas on, 4 psi (230 Torr), duration 0.1 @ t = 0.4 s attempt lgap = 30 mm, rgap = 17 mm went vertically unstable **** shot 21 Is the drop in threshold due to higher elongation??...this shot go to lower elongation. Kaiser helium gas on, 4 psi (230 Torr), duration 0.1 @ t = 0.4 s attempt lgap = 25 mm, rgap = 20 mm went vertically unstable at 0.88 s **** shot 22 Kaiser helium gas on, 4 psi (230 Torr), duration 0.1 @ t = 0.25 s attempt lgap = 20 mm, rgap = 20 lower elongation .. fizzle **** shot 23 Kaiser helium gas on, 4 psi (230 Torr), duration 0.1 @ t = 0.25 s attempt lgap = 20 mm, rgap = 20 lower elongation .. fizzle **** shot 24 Kaiser helium gas on, 4 psi (230 Torr), duration 0.1 @ t = 0.25 s attempt lgap = 20 mm, rgap = 20 lower elongation .. fizzle **** shot 25 Kaiser helium gas on, 4 psi (230 Torr), duration 0.1 @ t = 0.25 s attempt lgap = 20 mm, rgap = 20 lower elongation .. fizzle **** shot 26 good shot with lower elongation... lgap = 20 mm , rgap = 20 mm falls right on previous scaling! |
| Physics Operator Summaries |
| Entered: Jul 7 2004 04:37:10:723PM |
| Author: To Be Determined |
| Physop Summary for Thursday, May 11, 2000 MP#262 Effect of Main Chamber Recycling on H-mode threshold and confinement SL: Pitcher PO: Wolfe/Granetz EO: Dekow Setup and Run Plan Engineering: ------------ ECDC overnight in D2, turn off 2 hours before run Power system setup as on 1000510021 EXCEPT: Invert time on tf changed to 1.6 Voltage on EFC changed to 900V Gas setup - fill B-top 6 psi of D2 Hybrid enabled fill B-side lower 1 psi of Ar Hybrid DISABLED leave B-side upper as is Hybrid DISABLED fill C-side 30 psi of D2 Hybrid enabled leave J-bottom as is Hybrid DISABLED The following gate valves should be enabled, assuming there are no vacuum problems: VUV ECE DNB Run Plan: --------- We will investigate the effects of the left gap on ICRF heated H-mode discharges. We use a constant right gap, relatively large (~18 mm), but consistent with good ICRF coupling. We use 0.8 MA, 5.3 T, as in 990921004, with long ICRF power ramps to determine threshold power. We vary the left gap from 0 mm to the maximum possible, using a relatively short plasma to ease stability problems. We will have three target plasma densities, (line integral densities = 0.7, 1.0, 1.4), and 5 left gaps (0 mm, 5 mm, 10 mm, 20 mm, 30 mm). We will attempt to correlate changes in the confinement properties with changes in the edge profiles. Starting Condition: 0.8 MA, 5.3 T, current flat-top to 1.5 s, line-integral density = 1.0, 10 mm left gap (based on 1000510021, with reduced current, increased tf, adjusted left gap) RF ramp: 0.4 MW at t = .55 s --> 2.0 MW at t = 1.1 s (depending on available power, we may want to extend the ramp to higher powers, e.g. 3.2 MW at t = 1.5 s) Results: --------- We got through most of the gap scan at 1.0e20, no other densities were attempted. The largest inner gap obtained was about 25mm; larger gaps resulted in vertical instabilities, with n/ncrit>1.2 . The outer gap was kept at about 20mm; the RF seemed to like this, especiallt J-port. On the larger inner gaps, there was a tendency for the outer gap to shrink, apparently because the RCUR was doing a better job than CLEARIN in getting what was asked for. We wanted to use D and E antennas to get to high power, but E was out of action due to an arc in the phase shifter. We started the run using only D-port, up to 1.5MW or so; J-port was run later in the shot, and also produced H-modes, at higher power than D. A comparison may tell something about the relative heating efficiency of the two systems. For the limited plasmas, we wanted to combine the two systems to get enough power to get into H-mode, but this failed after several attempts. It's not clear why, since D and J were run together earlier without problems. Spencer got a nice linear dependence of threshold power on inner gap, down to 5mm. The projected value at zero gap was about 1.8MW, which was just over what we managed to get in, and we did not get any limiter h-modes. Spencer noted that the elongation was varying along with gap, so we tried to get a reduced elongation point at a gap>2cm, by increasing zxu to bring the top down. This effort was met by three fizzles and a mysterious TF failure, before we finally got it on the last shot. The elongation came down to 1.65, which wasn't quite as far as we wanted. As anticipated, the gap scan was a challenge, only partially met. It might be better to try this with a smaller outer gap, so the elongation is reduced somewhat. Either that, or spend a lot of effort trying to improve the fast vertical control, or run at somewhat higher current so li is lower. Shot summary: ------------- setup for shot#1: ------------------- load from 1000510021 Ip to 800kA ic_ef4 from 3000 to 2500 clearin from -.01,-.00975 to -.012 rcur from .663 to .662 zxu from ~.048 to .058 tf to -150000 pg1 puff from 60msec to 40msec (Ar was actually not turned on today) result: fizzle shot#2: fixed (?) the fizzle by tweaking Bz and Br; disrupted vertically at .25sec shot#3: reduced vertical thrash at .25sec by dropping early nl4 program to decrease li at diversion time. Seemed to work partly; the shots went, but still had some residual thrash that was caught by EFC shot4-7: scan inner gap in to 0. (actually dsep~-0.001m) shot8-11: inner wall limited (like 7) trying to increase power to get an H-mode. shot 12: repeat of shot#6 (5mm gap) shot 13-20: scan to increasing gap; lots of vertical instability disruptions, some success. One post-disruption fizzle along the way. It was found to be useful to slow down the CLEARIN ramp and allow the RCUR to overswing outward a little in the time period between .5 and .6sec to avoid an early vertical instability. See, e.g., shot#18. shot 21:attempt to reduce elongation at same inner gap as 19, but also tried to increase outer gap to nominal 2cm. Disrupted early. shot 22-26: attempts to reduce elongation of shot 18 (20mm gap both sides). Three fizzles, one no-tf dud, one success (#26) Problems: --------- We had one long delay due to a computer cluster hang; twf finally got it cleared by rebooting CMODA. On shot#25 the TF failed to fire. We were unable to discover the cause. Speculation included possibility that the scanner failed to clear or the CAMAC supply enable didn't happen. No evidence for either. We also observed a large signal on the TF bus voltage trace beginning at ~3.3sec. It turns out this signal has been showing up during and after normal shots all along, although we still don't understand where it comes from. The difference on this shot is that it seemed to start at 3.3sec, rather than being there from much earlier in the shot. The fizzles on 22-24 are not understood. The CII level was a little high, and appeared not to burn out, but no unusual peaks appeared on the RGA, and the fields looked as they had all day. The final tweak was dropping Br0 by .5mT, on shot#25, but it may well have come back on its own. Scorecard: ---------- tests 0 Duds 1 (no TF) Fizzles 5 Plasmas 20 ------ -- shots 26 |
| Session Leader Comments | |||
| May 11 2000 09:24:56:483AM | 1000511002 | Spencer Pitcher | Kaiser helium gas on discharge disrupts early t = 0.3 s |
| May 11 2000 09:54:34:623AM | 1000511003 | Spencer Pitcher | no Kaiser gas rgap = 21 mm , lgap = 15 mm RF ratty jumps to H-mode at Prf = 0.8 MW |
| May 11 2000 10:38:52:873AM | 1000511004 | Spencer Pitcher | Kaiser helium gas on, 4 psi (230 Torr), duration 0.1 @ t = 0.4 s abandon E antenna, focus on D, put J late in shot lgap = 12 mm , rgap = 20 mm jumps to H-mode at 1.0 MW |
| May 11 2000 10:39:14:950AM | 1000511005 | Spencer Pitcher | Kaiser helium gas on, 4 psi (230 Torr), duration 0.1 @ t = 0.4 s abandon E antenna, focus on D, put J late in shot lgap = 12 mm , rgap = 24 mm >>> mistake jumps to H-mode at 1.1 MW |
| May 11 2000 11:03:01:640AM | 1000511006 | Spencer Pitcher | Kaiser helium gas on, 4 psi (230 Torr), duration 0.1 @ t = 0.4 s abandon E antenna, focus on D, put J late in shot lgap = 4 mm , rgap = 23 mm jumps to H-mode at 1.4 MW |
| May 11 2000 11:21:47:763AM | 1000511007 | Spencer Pitcher | Kaiser helium gas on, 4 psi (230 Torr), duration 0.1 @ t = 0.4 s abandon E antenna, focus on D, put J late in shot lgap = 0 mm , rgap = 23 mm no H-mode |
| May 11 2000 11:40:08:293AM | 1000511008 | Spencer Pitcher | Kaiser helium gas on, 4 psi (230 Torr), duration 0.1 @ t = 0.4 s D and J antennas......D faulted lgap = 0 mm , rgap = 23 mm no H-mode |
| May 11 2000 11:58:47:200AM | 1000511009 | Spencer Pitcher | Kaiser helium gas on, 4 psi (230 Torr), duration 0.1 @ t = 0.4 s D and J antennas......no D lgap = 0 mm , rgap = 23 mm no H-mode |
| May 11 2000 12:48:02:297PM | 1000511010 | Spencer Pitcher | Kaiser helium gas on, 4 psi (230 Torr), duration 0.1 @ t = 0.4 s D and J antennas......D faulted lgap = 0 mm , rgap = 23 mm no H-mode |
| May 11 2000 12:48:25:483PM | 1000511011 | Spencer Pitcher | Kaiser helium gas on, 4 psi (230 Torr), duration 0.1 @ t = 0.4 s D and J antennas......D faulted lgap = 0 mm , rgap = 23 mm no H-mode |
| May 11 2000 01:26:10:750PM | 1000511012 | Spencer Pitcher | Kaiser helium gas on, 4 psi (230 Torr), duration 0.1 @ t = 0.4 s go back to shot 6...D antenna only, J later lgap = 6 mm , rgap = 23 mm H-mode at Prf = 1.4 MW....good shot, good repeat of shot 6 |
| May 11 2000 01:27:24:030PM | 1000511013 | Spencer Pitcher | Kaiser helium gas on, 4 psi (230 Torr), duration 0.1 @ t = 0.4 s lgap = 20 mm , rgap = 20 mm H-mode at Prf = 0.79 MW ....big drop in threshold! Is this left gap or elongation? |
| May 11 2000 01:27:53:450PM | 1000511014 | Spencer Pitcher | Kaiser helium gas on, 4 psi (230 Torr), duration 0.1 @ t = 0.2 s no plasma...(Granetz took over from Wolfe) |
| May 11 2000 03:06:20:247PM | 1000511015 | Spencer Pitcher | Kaiser helium gas on, 4 psi (230 Torr), duration 0.1 @ t = 0.2 s stability problem, disrupt t = 0.57 s |
| May 11 2000 03:06:41:250PM | 1000511016 | Spencer Pitcher | Kaiser helium gas on, 4 psi (230 Torr), duration 0.1 @ t = 0.2 s stability problem, disrupt t = 0.55 s |
| May 11 2000 03:07:03:670PM | 1000511017 | Spencer Pitcher | Kaiser helium gas on, 4 psi (230 Torr), duration 0.1 @ t = 0.2 s stability problem, disrupt t = 0.54 s |
| May 11 2000 03:07:25:000PM | 1000511018 | Spencer Pitcher | Kaiser helium gas on, 4 psi (230 Torr), duration 0.1 @ t = 0.2 s push RF later lgap = 20 mm, rgap = 17 mm good plasma, approx repeat of shot 13 |
| May 11 2000 03:29:56:437PM | 1000511019 | Spencer Pitcher | Kaiser helium gas on, 4 psi (230 Torr), duration 0.1 @ t = 0.2 s lgap = 25 mm, rgap = 17 mm good plasma |
| May 11 2000 03:30:18:420PM | 1000511020 | Spencer Pitcher | Kaiser helium gas on, 4 psi (230 Torr), duration 0.1 @ t = 0.4 s attempt lgap = 30 mm, rgap = 17 mm went vertically unstable |
| May 11 2000 04:20:34:110PM | 1000511021 | Spencer Pitcher | Is the drop in threshold due to higher elongation??...this shot go to lower elongation. Kaiser helium gas on, 4 psi (230 Torr), duration 0.1 @ t = 0.4 s attempt lgap = 25 mm, rgap = 20 mm went vertically unstable at 0.88 s |
| May 11 2000 04:20:53:797PM | 1000511022 | Spencer Pitcher | Kaiser helium gas on, 4 psi (230 Torr), duration 0.1 @ t = 0.25 s attempt lgap = 20 mm, rgap = 20 lower elongation .. fizzle |
| May 11 2000 04:21:19:717PM | 1000511023 | Spencer Pitcher | Kaiser helium gas on, 4 psi (230 Torr), duration 0.1 @ t = 0.25 s attempt lgap = 20 mm, rgap = 20 lower elongation .. fizzle |
| Physics Operator Comments | |||
| May 11 2000 06:34:46:233AM | Steve Wolfe | Setup for run 1000511 Run to start at 09:00 and end at 17:00. MP # 262 Effect of main chamber recycling on H-Mode confinement SL: Pitcher PO: wolfe/granetz Engineering: ------------ ECDC overnight in D2, turn off 2 hours before run Power system setup as on 1000510021 EXCEPT: Invert time on tf changed to 2.0 Voltage on EFC changed to 900V Gas setup - fill B-top 6 psi of D2 Hybrid enabled fill B-side lower 1 psi of Ar Hybrid DISABLED leave B-side upper as is Hybrid DISABLED fill C-side 30 psi of D2 Hybrid enabled leave J-bottom as is Hybrid DISABLED The following gate valves should be enabled, assuming there are no vacuum problems: VUV ECE DNB Run Plan: --------- We will investigate the effects of the left gap on ICRF heated H-mode discharges. We use a constant right gap, relatively large (~18 mm), but consistent with good ICRF coupling. We use 0.8 MA, 5.3 T, as in 990921004, with long ICRF power ramps to determine threshold power. We vary the left gap from 0 mm to the maximum possible, using a relatively short plasma to ease stability problems. We will have three target plasma densities, (line integral densities = 0.7, 1.0, 1.4), and 5 left gaps (0 mm, 5 mm, 10 mm, 20 mm, 30 mm). We will attempt to correlate changes in the confinement properties with changes in the edge profiles. Starting Condition: 0.8 MA, 5.3 T, current flat-top to 1.5 s, line-integral density = 1.0, 10 mm left gap (based on 1000510021, with reduced current, increased tf, adjusted left gap) RF ramp: 0.4 MW at t = .55 s --> 2.0 MW at t = 1.1 s (depending on available power, we may want to extend the ramp to higher powers, e.g. 3.2 MW at t = 1.5 s) | |
| May 11 2000 06:57:40:747AM | Steve Wolfe | setup for shot#1: ------------------- load from 1000510021 Ip to 800kA ic_ef4 from 3000 to 2500 clearin from -.01,-.00975 to -.012 rcur from .663 to .662 zxu from ~.048 to .058 tf to -150000 pg1 puff from 60msec to 40msec (Ar not on for shot#1) TF invert at 1.6 instead of 2.0 (as stated above); program invert at 1.5 | |
| May 11 2000 07:00:54:560AM | Steve Wolfe | coldstart at 7:00 all matrices respond, no errors | |
| May 11 2000 07:03:19:920AM | Steve Wolfe | change segment #2 title to "CSP gap scan" reload model | |
| May 11 2000 09:04:42:030AM | 1000511001 | Steve Wolfe | shot#1: supposed to be 800ka, 1e20, gapin=.010, gapout=.018, B=5.4 fizzle. bz and br both look a little bit negative Next shot: ef4 from -1280->-1265 br0 from -.0005->0.00 |
| May 11 2000 09:34:48:997AM | 1000511002 | Steve Wolfe | shot#2: ef4 from -1280->-1265, br0 from -.0005->0.00 disruption early, at .25sec startup has a pretty bad hesitation too. looks like a vertical instability; ends up going up. The only difference at that time between this shot and 1000510012 is the density Next shot: load slower density ramp, drop early clearin points to -.012 |
| May 11 2000 09:52:50:810AM | 1000511003 | Steve Wolfe | shot#3: load slower density ramp, drop early clearin points to -.012 plasma, still has a big thrash at .27, makes it through but not happy. Injection at .67s. 2h-moes Both gaps are a little large: inner 15mm, outer 21mm next shot: clearin from -.012 ->-.016 |
| May 11 2000 10:06:30:140AM | 1000511004 | Steve Wolfe | shot#4: clearin from -.012 ->-.016, aim for 10mm inner gap, 17mm outer. plasma, still a thrash around .25, but better. 2 h-modes, going eda. inner gap=12mm, outer=20mm next shot, go for 5mm inner gap. clearin: -.016->-024, rcur:.662->.658 (early point to .660) |
| May 11 2000 10:29:25:467AM | 1000511005 | Steve Wolfe | shot#5: go for 5mm inner gap. clearin: -.016->-024, rcur:.662->.658 (early point to .660) plasma, h-mode@.9sec, looks elm-free. disruption at 1.66sec thrash at .25s is still there and ugly. inner gap didn't change; outer to 23mm???? clearin still at 0.016??? next shot: really change clearin from -.016->-.024 also drop early density a bit more. |
| May 11 2000 10:43:20:280AM | 1000511006 | Steve Wolfe | shot#6: go for 5mm inner gap. really change clearin from -.016->-.024 also drop early density a bit more. plasma 1.9s, still has the .25s thrash. hmode at 1.03sec, elm-free, inner=5mm, outer=22mm next shot: try for marginally limited. |
| May 11 2000 11:21:41:763AM | 1000511007 | Steve Wolfe | shot#7: try for marginally limited. clearin: -.024->-.03, rcur: -.658->-.656 plasma, looks bright on inner wall. inner=0, outer=23mm, dsep=-1mm, no h-mode. next shot:repeat with more power (add J in) |
| May 11 2000 11:26:26:670AM | 1000511008 | Steve Wolfe | shot#8: repeat with more power (add J in) plasma no h-mode. only about 1.5MW d faulted when j came on. next shot: repeat, try again for inner wall h-mode |
| May 11 2000 11:48:50:340AM | 1000511009 | Steve Wolfe | shot#9:repeat, try again for inner wall h-mode plasma , no h-mode. only one antenna, d was mistuned. Next shot: try again (probably two more tries) |
| May 11 2000 12:04:56:233PM | 1000511010 | Steve Wolfe | shot#10:repeat, try again for inner wall h-mode plasma. no h-mode. to the untutored eye, it looks like shot 8 |
| May 11 2000 12:23:01:013PM | 1000511011 | Steve Wolfe | shot#11:repeat, try again for inner wall h-mode no h-mode, still not stacking the antennas. next shot: back to shot#6 |
| May 11 2000 12:41:19:357PM | 1000511012 | Steve Wolfe | shot#12:repeat of shot #6, nominal 5mm inner gap plasma, h-mode at 1.02sec next shot: 2cm inner gap. |
| May 11 2000 12:53:30:967PM | 1000511012 | Steve Wolfe | shot#13:go for 2cm inner gap. clearin: -.024->-.008 from .42sec:1.5sec rcur: .658->.665, except point at (.386,.668) Granetz taking over as physop (after the load, before the shot) |
| May 11 2000 01:01:18:577PM | 1000511013 | Robert Granetz | Granetz now substituting as Physop for Steve Wolfe for the next 1-2 hours. |
| May 11 2000 01:08:21:577PM | 1000511013 | Robert Granetz | Shot 13 -- Plasma. Disrupted at t=1.54 s. Left gap=19-20 mm, Right gap=18-20 mm. nl_04=1.0e20 m-2 (target density). EDA H-mode starting at t=0.72 s. Next shot: increase inner gap to 27 mm, keep outer gap at 20 mm. |
| May 11 2000 01:22:53:827PM | 1000511014 | Robert Granetz | Shot 14 -- Fizzle. Only a tiny Br0 difference; everything else identical to preceding shot. Next shot: change Br0 by -0.0003 T |
| May 11 2000 01:47:14:373PM | 1000511015 | Robert Granetz | Shot 15 -- Plasma. Disrupted at t=0.57 s. Went vertically unstable. EFIT n/ncrit --> 1.24. Next shot: reduce inner gap to 25 mm (from 27) and reduce outer gap by 1 mm (because Spencer doesn't want to change the x-points). |
| May 11 2000 02:07:08:560PM | 1000511016 | Robert Granetz | Shot 16 -- Plasma. Disrupted at t=0.56 s. Looks the same as the previous shot. EFIT n/ncrit --> 1.35 on this one, even though the left gap was supposed to be smaller. The x-ray centroid looks like a classic VDE, but EFC current did not rail on either shot. Strange. Next shot: reload shot 13 (20 mm inner gap, 20 mm outer gap) |
| May 11 2000 02:08:05:607PM | 1000511016 | Robert Granetz | Wolfe returns to Physop before shot 17 (but after it was loaded) |
| May 11 2000 02:39:20:840PM | 1000511017 | Steve Wolfe | shot#17: reload of 13 disrupts at 0.53, pf breaker pulled after. n/nc peaks around that time on shot 13 as well, ~1.2 next shot: delay clearin max and make right gap smaller before .6sec Josh is working on a computer hang. |
| May 11 2000 02:55:31:140PM | 1000511018 | Steve Wolfe | shot#18: delay clearin max and make right gap smaller (hold rcur out longer) before .6sec delay rf by 200msec plasma, h-mode at 1.06sec inner=20mm, outer=19mm next shot, another 6mm on inner |
| May 11 2000 03:17:06:687PM | 1000511019 | Steve Wolfe | shot#19: another 6mm on clearin, to -.002, 3mm on rcur, to .669 plasma h-mode at 1.02sec, left=24mm, right=17mm, overcompensating on rcur. n/nc=1.17 next shot: another 6mm on clearin, 1.5mm on rcur |
| May 11 2000 03:26:47:983PM | 1000511020 | Steve Wolfe | shot#20: another 6mm on clearin, to +.004, 1.5mm on rcur, to .6705, 3cm or bust! Busted! disrupted at .80, strong vertical instability next shot back to 19, reduce height to drop elongation. |
| May 11 2000 03:54:32:577PM | 1000511021 | Steve Wolfe | shot#21:back to 19, reduce height to drop elongation. zxu from .058->.078, also drop rcur back .669->.667 to increase right gap back to 20mm disrupted at .87sec, with n/nc=1.24, left=25mm, right=20mm, kappa=1.68 probably should have left the right gap alone, but while we're here, next shot: increase zxu to .098,drop zcur by .005 |
| May 11 2000 04:05:32:420PM | 1000511022 | Steve Wolfe | shot#22: change of plan, reload 18 and drop the height: zxu from .058->.088 fizzle. probably disruption effect; CII light is up. Br may have drifted up a tad. next shot: just go again. |
| May 11 2000 04:25:43:200PM | 1000511023 | Steve Wolfe | shot#23: change of plan, reload 18 and drop the height: zxu from .058->.088 another fizzle, should have tweaked something br dropped .5mT by itself, that's what I would have tweaked. cii is still at .003 (was .004 last shot). next shot: drop fill by 2msec |
| May 11 2000 04:31:58:793PM | 1000511024 | Steve Wolfe | shot#24: change of plan, reload 18 and drop the height: zxu from .058->.088 drop fill by 2msec where has my plasma gone? drop br by .5mT |
| May 11 2000 04:43:20:640PM | 1000511025 | Steve Wolfe | shot#25: drop br by .5mT NO TF!*)(&)#%*&#*$(@(O One more try |
| May 11 2000 05:15:10:653PM | 1000511026 | Steve Wolfe | shot#26: One more try long delay while we scratch our heads about why the tf didn't go. plasma, disrupts at 1.6sec, h-mode at .92sec, prf=.88MW eda at 1.02s, .95MW, good fast current rise, good cii burnout. left gap=20m, right=19mm, kappa=1.65 |
| Engineering Operator Comments | ||||
| Shot | Time | Type | Status | Comment |
| 1 | 08:56:31:920AM | Plasma | Ok | |
| 2 | 09:10:57:060AM | Plasma | Ok | |
| 3 | 09:36:57:653AM | Plasma | Ok | |
| 4 | 09:56:57:153AM | Plasma | Ok | |
| 5 | 10:15:59:110AM | Plasma | Ok | |
| 6 | 10:36:58:780AM | Plasma | Ok | |
| 7 | 10:58:47:903AM | Plasma | Ok | |
| 8 | 11:20:02:030AM | Plasma | Ok | |
| 9 | 11:40:34:780AM | Plasma | Ok | |
| 10 | 11:59:28:810AM | Plasma | Ok | |
| 11 | 12:18:26:903PM | Plasma | Ok | |
| 12 | 12:38:17:810PM | Plasma | Ok | |
| 13 | 12:57:03:530PM | Plasma | Ok | |
| 14 | 01:15:54:687PM | Plasma | Ok | |
| 15 | 01:30:18:733PM | Plasma | Ok | |
| 16 | 01:49:15:233PM | Plasma | Ok | |
| 17 | 02:08:33:873PM | Plasma | Ok | OH2U,L and EF1L converter commutation faults |
| 18 | 02:45:24:093PM | Plasma | Ok | |
| 19 | 03:02:57:903PM | Plasma | Ok | |
| 20 | 03:22:08:140PM | Plasma | Ok | |
| 21 | 03:42:19:013PM | Plasma | Ok | |
| 22 | 04:00:04:420PM | Plasma | Ok | |
| 23 | 04:13:43:403PM | Plasma | Ok | |
| 24 | 04:27:34:030PM | Plasma | Ok | |
| 25 | 04:40:43:497PM | Plasma | Bad | No TF |
| 26 | 05:06:55:153PM | Plasma | Ok | |