| Miniproposals | ||||||||||
|
| Operators | |
| Session leader(s): | Earl Marmar |
| Physics operator(s): | Steve Wukitch |
| Engineering operator(s): | Gary Dekow,Andy Pfeiffer,Ed Fitzgerald |
| Engineering Operator Run Comment |
| PO-plan: MP643 Optimization of I-mode in normal field, USN |
| Session Leader Plans |
| Entered: Jul 13 2012 08:54:55:570AM |
| Author: Earl Marmar |
| MP643 Optimization of I-mode in normal field, USN
SL: Marmar/Hubbard PO: Wukitch Shot sequence plan 1) Use 1101209026 as starting equilibrium, but lower Ip to 1.1 MA, raise Bt to 5.8 T 2) Post-boron ICRF recovery, until reliable 4 MW (6-8 shots) 3) Evaluate post-boron I-mode with target shot 1101209024/26, 4.5 MW ICRF, but reduce ICRF flattop time to 0.3 seconds, to reduce upper divertor energy deposition, as in figure 3. (3 shots) 4) Reduce density shot to shot, evaluating I-mode access, radiation, H-mode access (if reached). Densities (nl04) should be 1.0, 0.7, 0.5, 0.4e20. Watch for significant moly/radiated power and adjust neon as required. If flat-top runaways or locked modes become too problematic, stop the density scan and don't go lower. (8-10 shots). 5) From step 4, choose the lowest density with good I-mode performance. Assuming there was no transition to H-mode, repeat these conditions with 0.5 s ICRF flattop (2 shots). 6) If H-mode still not seen, apply maximum available ICRF power for these conditions (4 shots). 7) Do the high density scan (nl_04=1.5, 2.0, 2.25, 2.5 e20), 4.5 MW, 0.3 s ICRF flattop. If ICRF reaches high density limit (neutral pressure), truncate the scan. If there appears to be an L-mode target density limit for accessing I-mode (even with good RF), try fueling to higher density after getting into I-mode at lower target density. For these higher density cryopumped shots, additional fueling from the high field side with NINJA will probably be required; this has also been shown to be helpful with the ICRF density limit. (10 shots) 8) Using the highest density shot with good I-mode from step 7, increase ICRF flattop to 0.5 s, and, then, if no transition to H-mode seen, increase power in subsequent shots to max available (as in step 6). (6 shots) The MP plan is based on a 10 hour run-day. Since we are planning for 8 hours today, we'll need to cut back on the later parts of the sequence. The low density shots, steps 4-6, are the highest priority. |
| Physics Operators Plans |
| Entered: Jul 12 2012 04:58:37:580PM |
| Author: Steve Wukitch |
| -----------------
Engineering Setup ----------------- PO-plan: MP643 Optimization of I-mode in normal field, USN Run begins at 09:00 and ends at 17:00 Power systems as on: 1101209026 Acoil: +Dtop -Dbot -Jtop +Jbot (standard) Hybrid Enabled Gas setup: Fill B-Top with 6 psi D2 Hybrid enabled (PG4) fill B-side lower with 1 psi Ar Hybrid DISABLED (PG1) leave B-side upper as is Hybrid DISABLED (PG2) fill B-main (C-side) with 40 psi D2 Hybrid enabled (PG3) fill NINJA with 10 psi D2 DISABLED fill H-bottom with 3 psi Ne Hybrid DISABLED (PG5) Enable gate-valves and shutters: ECE, VUV, HiREX Sr, Xeus/LoWEUS Leave z-bolo shutter as is (should be open) Torvac gatevalve toggle (yes/no): no Boronization(yes/no): no Overnight ECDC (yes/no): yes ICRF(yes/no): yes LH(yes/no): allowable Cryopump (yes/no): yes DNB (yes/no): allowable Vessel temperature: 35/35/35 ------------------------------ ECDC Parameters (if requested) ------------------------------ gas and pressure: D2 at 2e-4 Torr sweep: 44/45/103 cm scan: 20/120 s ------------------------------ Physop Plan ------------------------------ Startup will be from 1120711023 with modification to prepuff due to cryopump Start with 1101209026 BT=5.6T, Ip=1.2 MA, nl04=1.1 which has lower delta_upper than desired: kappa=1.7, delta_upper 0.7 to â?¥0.8 delta_lower .25 to â?¥.3 We chose Ne for low Z seeding: allows Churchill to piggyback (N interfers with CXR signals) easier to switch to N2 Seeding parameters will start with PG5 0.4-0.55s at 60 V follow Session Leader plan ------------------------------ |
| Session Leader Summaries |
| Entered: Jul 16 2012 01:56:39:333PM |
| Author: Earl Marmar |
| While there were a number of shots with early disruptions, we were able to make good progress on the miniproposal, particularly with respect to the density scan portion of the plan. Discharges of interest were at 1.1 MA (from the first part of the run) and 1.2 MA. Attempts to run 1.1 MA and 1.0 MA ran into difficulties later in the day (disruptions, impurity issues, poor heating, possible locked modes in some cases). Line average density was scanned from 1.5e20 to 2.8e20; most shots had ICRF power at or above 4 MW, and many had 5.0 or 5.5. I-mode access was clearly sensitive to density, and in no case was H98 larger than 0.8. Shots for further analysis: 1, 3, 6, 7, 10, 13, 16, 17, 18, 19, 22, 24, 30, 31. Shot 30 had the only clear I to H transition during the day.
There were a number of shots that exhibited mildly enhanced H98 (above 0.5) and high central Te, but did not show clear signs of an edge temperature barrier or obvious changes to fluctuations. Perhaps the best example is shot 10. Raising the density gave I-mode (see e.g. shots 17 and 19). Shot 19 had a density ramp-up, with the transition to I-mode occurring when nel reached about 1.3e20. |
| Physics Operator Summaries |
| Entered: Jul 13 2012 05:15:24:783PM |
| Author: Steve Wukitch |
| Run Summary
Run was plagued by disruptions which complicated the run plan. We had a few disruptions ~0.45 s that appeared to be cured by changing the IP gain at 0.32 s to 4 from 5. Plasmas were diverting near cross over and we lost control at a critical time. We were unable to run a good plasma at 1.1 MA in USN. We were either disrupting or experiencing lock modes. I-modes that were obtained were not of particularly high quality. Startup was fairly robust and we needed only to pay attention to prefill pressure to control run aways. attempts 31 disruptions 13 fizzles 1 plasmas 30 |
| Session Leader Comments | |||
| Jul 13 2012 09:17:55:070AM | 1120713001 | Earl Marmar | step 1/2 - 1.1 MA, 5.9 T (will adjust to 5.8 for next shot)
density above target at start of RF, and then rises further looks like a significant MARFE; very large signals on H/D spectrometer not much heating; solidly L-mode (or below) |
| Jul 13 2012 09:27:55:273AM | 1120713002 | Earl Marmar | nl_04 target to 0.9e20
good 2 MW ICRF shot (J-port faulting) no MARFE this time, better heating, L-mode or slightly above modest density rise during RF |
| Jul 13 2012 09:44:43:350AM | 1120713003 | Earl Marmar | good 4 MW ICRF shot
H98 is starting to creep up above 0.5, at least until the density increases during the RF NINJA also contributes some fueling after 1 second (helium) |
| Jul 13 2012 10:01:46:850AM | 1120713004 | Earl Marmar | disrupt at very start of RF pulse
big increase in Prad just prior to the disruption |
| Jul 13 2012 10:32:43:770AM | 1120713005 | Earl Marmar | early disruption (200 msec) |
| Jul 13 2012 10:33:30:730AM | 1120713006 | Earl Marmar | good 4 MW shot
still a bit of fueling with ICRF, but not much might be getting close, but no clear I-mode |
| Jul 13 2012 10:39:32:480AM | 1120713007 | Earl Marmar | 4 MW shot
disrupt right after RF turnoff |
| Jul 13 2012 11:09:03:253AM | 1120713009 | Amanda Hubbard |
Filling in for Earl. Disrupts 0.45 s, vertical instability. Going to try going back to the lower B and Ip, but more power to see if we get I-mode that way. |
| Jul 13 2012 11:35:07:520AM | 1120713010 | Amanda Hubbard | Got full shot, 4.5 MW, (5.8 T, 1.1 MA).
Very high Te and big sawteeth, but not an evident edge barrier. Next: Reduce Bt to 5.6 T to put ICRF more on axis, and try to reduce density which has been at nel 10^20, nebar 1.5, on the high side for I-modes at this current. Also request another 0.5 MW. Radiation is fairly high, but Matt reports it is mostly Moly. First, catch our I-mode. Then try to reduce density further as per run plan... |
| Jul 13 2012 11:48:23:073AM | 1120713011 | Amanda Hubbard | Disrupts - x-ray centroid indicates vertical instability at 0.4 secs. Try again. |
| Jul 13 2012 11:51:39:993AM | 1120713012 | Amanda Hubbard | Disruption at exactly the same time, unfortunately. |
| Jul 13 2012 04:36:05:577PM | 1120713024 | Earl Marmar | repeat 22 (1.2 MA) but add PG3 from 0.8 to 0.9 s
very small density increase, RF trips, briefly I-mode'ish and then never recovers after the trips |
| Jul 13 2012 04:35:34:653PM | 1120713029 | Earl Marmar | repeat 24 (1.2 MA) but increase magnitude of PG3 puff (still from 0.8 to 0.9 s)
I-mode'ish, then RF trips |
| Jul 13 2012 04:48:54:217PM | 1120713030 | Earl Marmar | PG3 puff now from 0.8 to 0.95 s
Possible H-mode transition, RF trip |
| Physics Operator Comments | |||
| Jul 13 2012 09:20:56:317AM | 1120713001 | Steve Wukitch | 001 request: BT=5.8 T, Ip=1.1 MA, nl_04~1
H-bottom (PG5) enabled - 0.4-0.55s at 60 V loaded seg1 startup from 11207011023 loaded seg2 from 1101209026 Load at 13-Jul-2012 08:55:04.00 result: plasma - BT=5.9 T, nl_04 ramping - too much neon? next: reduce Ne to 25 V reduce BT from 5.9 (163.6) to 5.8 T (161) reduce nl04 to 0.9 Load at 13-Jul-2012 09:17:14.00 |
| Jul 13 2012 09:28:20:890AM | 1120713002 | Steve Wukitch | 002 request: BT=5.8 T, Ip=1.1 MA, nl_04~0.9
result: plasma - BT~5.8 T, Ip~1.1, nl04~1 at RF turn on J failed? next: Ne to 50 V Load at 13-Jul-2012 09:27:48.00 |
| Jul 13 2012 09:40:48:300AM | 1120713003 | Steve Wukitch | 003 request: BT=5.8 T, Ip=1.1 MA, nl_04~0.9
result: plasma - RF fueling next: lower nl04~0.8 Load at 13-Jul-2012 09:39:51.00 |
| Jul 13 2012 10:02:22:003AM | 1120713004 | Steve Wukitch | 004 request: BT=5.8 T, Ip=1.1 MA, nl_04~0.8
result: plasma - disruption ~0.7 s killer Fe injection next: raise nl04~0.9 lower prepuff to 47 ms from 52 ms move Ar puff to 0.3-0.4 s at 100 V (PG1) Load at 13-Jul-2012 10:00:43.00 |
| Jul 13 2012 10:15:21:500AM | 1120713005 | Steve Wukitch | 005 request: BT=5.8 T, Ip=1.1 MA, nl_04~0.8
result: plasma - disruption ~0.2 s higher fill pressure - result next: leave prepuff fix Ar pulse Load at 13-Jul-2012 10:13:55.00 |
| Jul 13 2012 10:27:36:387AM | 1120713006 | Steve Wukitch | 006 request: BT=5.8 T, Ip=1.1 MA, nl_04~0.8
result: plasma - startup is back prefill pressure is still higher than 003 next: Ne to 30 V (PG5) leave prepuff |
| Jul 13 2012 10:30:06:427AM | 1120713006 | Steve Wukitch | 006 request: BT=5.8 T, Ip=1.1 MA, nl_04~0.8
result: plasma - startup is back prefill pressure is still higher than 003 next: Ne to 30 V (PG5) leave prepuff as is Load at 13-Jul-2012 10:29:37.00 |
| Jul 13 2012 10:42:57:850AM | 1120713007 | Steve Wukitch | 007 request: BT=5.8 T, Ip=1.1 MA, nl_04~0.9
result: plasma - disruption at 1.26s prefill pressure better but disruption will mess it up again next: reduce prepuff by 3 ms BT to 5.6 T (158 kA) Ip to 1.2 MA Load at 13-Jul-2012 10:41:23.00 |
| Jul 13 2012 10:59:39:943AM | 1120713008 | Steve Wukitch | 008 request: BT=5.6 T, Ip=1.2 MA, nl_04~0.9
result: plasma -remarkably similar to 005 prefill pressure is higher current rise is too slow - need to reduce prepuff lower next: reduce prepuff by 3 ms BT to 5.6 T (158 kA) Ip to 1.2 MA Load at 13-Jul-2012 10:59:18.00 |
| Jul 13 2012 11:19:22:477AM | 1120713009 | Steve Wukitch | 009 request: BT=5.6 T, Ip=1.2 MA, nl_04~0.9
result: plasma - disruption 0.45 s prefill pressure is better TMX breaker - vertically unstable as a result next: reduce prepuff by 3 ms (41 ms) BT to 5.8 T (161 kA) Ip to 1.1 MA Load at 13-Jul-2012 11:10:48.00 |
| Jul 13 2012 11:32:58:940AM | 1120713010 | Steve Wukitch | 010 request: BT=5.8 T, Ip=1.1 MA, nl_04~0.9
result: plasma - better - I-mode looking Prf=4.5 next: increase prepuff by 3 ms (44 ms) BT to 5.6 T (158 kA) nl04~0.8 raise PRF to 5 MW Load at 13-Jul-2012 11:32:22.00 |
| Jul 13 2012 11:51:04:520AM | 1120713011 | Steve Wukitch | 011 request: BT=5.6 T, Ip=1.1 MA, nl_04~0.8
result: plasma - had hards - looks like I should have increased prepuff further disruption vertically unstable next: increase rcur prior to 0.4 s from 0.656 to 0.659 Load at 13-Jul-2012 11:47:36.00 |
| Jul 13 2012 12:03:52:893PM | 1120713012 | Steve Wukitch | 012 request: BT=5.6 T, Ip=1.1 MA, nl_04~0.8
result: plasma - disruption vertically unstable? prefill pressure is low next: increase prefill by 4 ms (45 ms) ZXU reduced at 0.4 s to 0.005 from 0.01 Load at 13-Jul-2012 12:03:21.00 |
| Jul 13 2012 12:19:18:350PM | 1120713013 | Steve Wukitch | 013 request: BT=5.6 T, Ip=1.1 MA, nl_04~0.8
result: plasma - FL RF faulting next: improve ZXU in rampdown (bring it down with the current) Load at 13-Jul-2012 12:18:03.00 |
| Jul 13 2012 12:34:56:940PM | 1120713014 | Steve Wukitch | 014 request: BT=5.6 T, Ip=1.1 MA, nl_04~0.8
result: plasma - another disruption at 0.45 s vertical instability? next: increase current to 1.2 MA change Ip gain to 4 at 0.32 s instead of 5 Load at 13-Jul-2012 12:32:27.00 |
| Jul 13 2012 12:57:51:123PM | 1120713015 | Steve Wukitch | 015 request: BT=5.7 T, Ip=1.2 MA, nl_04~0.8
result: plasma - rf is faulting less hesitation at OH cross over next: raise Ne to 50 V nl04 to 1 Load at 13-Jul-2012 12:56:40.00 |
| Jul 13 2012 01:12:23:530PM | 1120713016 | Steve Wukitch | 016 request: BT=5.6 T, Ip=1.2 MA, nl_04~1
result: plasma - next: nl04 to 1.2 Load at 13-Jul-2012 13:10:55.00 |
| Jul 13 2012 01:29:16:570PM | 1120713017 | Steve Wukitch | 017 request: BT=5.6 T, Ip=1.2 MA, nl_04~1.2
result: plasma - hards during startup next: nl04 to 1.1 at 0.8 s and ramp to 1.4 at 1.2 s lengthen RF pulse to 1.2 s increase prepuff by 2 ms (47 ms) Load at 13-Jul-2012 13:26:45.00 |
| Jul 13 2012 01:43:08:770PM | 1120713018 | Steve Wukitch | 018 request: BT=5.6 T, Ip=1.2 MA, nl_04~1.1-1.4
result: plasma - disruption at 1.1 s hards during startup next: pre-emptive lowering of prepuff by 5 ms (40 ms) neon to 60 V and delay to 0.5 s |
| Jul 13 2012 02:04:51:250PM | 1120713019 | Steve Wukitch | 019 request: BT=5.6 T, Ip=1.2 MA, nl_04~1.1-1.4
result: plasma - disruption at 1.2 s killer tungsten next: BT~5.55 T Ip~1.1 MA nl04~1.1 shorten Prf to 1 s Load at 13-Jul-2012 14:00:30.00 |
| Jul 13 2012 02:21:39:343PM | 1120713020 | Steve Wukitch | 020 request: BT=5.55 T, Ip=1.1 MA, nl_04~1.1
result: plasma - disruption at 0.95 s ugly - lets not repeat it next: repeat 017 BT=5.5, Ip=1.2, nl04~1.1 Load at 13-Jul-2012 14:21:05.00 |
| Jul 13 2012 02:34:41:397PM | 1120713021 | Steve Wukitch | 021 request: BT=5.5 T, Ip=1.2 MA, nl_04~1.1
result: plasma (fl) next: reload 017 BT=5.5, Ip=1.2, nl04~1.1 Load at 13-Jul-2012 14:34:17.00 |
| Jul 13 2012 02:49:26:127PM | 1120713022 | Steve Wukitch | 022 request: BT=5.5 T, Ip=1.1 MA, nl_04~1.1
result: plasma (fl) keeper next: Ip to 1.1 MA nl04=1.1 Load at 13-Jul-2012 14:48:46 |
| Jul 13 2012 03:25:51:457PM | 1120713024 | Steve Wukitch | 024 request: BT=5.5 T, Ip=1.2 MA, nl_04~1.2
result: plasma (fl) next: recall 023 move upper xpoint to smaller major radius RXU more negative by 5 mm. (from -0.015 to -.020) Load at 13-Jul-2012 15:25:16 |
| Jul 13 2012 03:37:19:567PM | 1120713025 | Steve Wukitch | 025 request: BT=5.5 T, Ip=1.1 MA, nl_04~1.1
result: plasma - disruption 0.7 s next: lower Ip to 1 MA Load at 13-Jul-2012 15:36:36 |
| Jul 13 2012 03:44:50:390PM | 1120713025 | Steve Wukitch | 025 request: BT=5.5 T, Ip=1.1 MA, nl_04~1.1
result: plasma - disruption 0.7 s next: lower Ip to 1 MA Load at 13-Jul-2012 15:44:15 |
| Jul 13 2012 03:55:26:790PM | 1120713026 | Steve Wukitch | 026 request: BT=5.5 T, Ip=1.0 MA, nl_04~1.1
result: plasma - locked mode?!? next: nl04~0.9 |
| Jul 13 2012 04:00:03:583PM | 1120713026 | Steve Wukitch | 026 request: BT=5.5 T, Ip=1.0 MA, nl_04~1.1
result: plasma - locked mode?!? next: nl04~0.9 Load at 13-Jul-2012 15:59:48 |
| Jul 13 2012 04:09:47:983PM | 1120713027 | Steve Wukitch | 027 request: BT=5.5 T, Ip=1.0 MA, nl_04~1
result: fizzle next: raise fill pressure pg4 from 40 to 45 ms Load at 13-Jul-2012 16:08:09 |
| Jul 13 2012 04:50:03:833PM | 1120713030 | Steve Wukitch | 030 request: BT=5.5 T, Ip=1.2 MA, nl_04~1.2
result: plasma next: nl04~0.7 Load at 13-Jul-2012 16:47:55.00 |
| Jul 13 2012 05:05:08:977PM | 1120713031 | Steve Wukitch | 031 request: BT=5.5 T, Ip=1.2 MA, nl_04~0.7
result: plasma next: EoR |
| Engineering Operator Comments | ||||
| Shot | Time | Type | Status | Comment |
| 1 | 09:02:41:290AM | Plasma | Ok | |
| 2 | 09:18:02:180AM | Plasma | Ok | |
| 3 | 09:32:17:090AM | Plasma | Ok | |
| 4 | 09:47:06:470AM | Plasma | Ok | |
| 5 | 10:01:44:193AM | Plasma | Ok | |
| 6 | 10:15:32:430AM | Plasma | Ok | |
| 7 | 10:31:32:243AM | Plasma | Ok | |
| 8 | 10:46:51:097AM | Plasma | Ok | |
| 9 | 11:00:04:737AM | Plasma | Ok | |
| 10 | 11:17:13:630AM | Plasma | Ok | |
| 11 | 11:33:06:860AM | Plasma | Ok | |
| 12 | 11:48:28:317AM | Plasma | Ok | |
| 13 | 12:04:02:120PM | Plasma | Ok | |
| 14 | 12:19:16:147PM | Plasma | Ok | |
| 15 | 12:33:20:980PM | Plasma | Ok | |
| 16 | 01:01:02:897PM | Plasma | Ok | |
| 17 | 01:13:37:577PM | Plasma | Ok | |
| 18 | 01:29:59:960PM | Plasma | Ok | |
| 19 | 01:48:05:910PM | Plasma | Ok | |
| 20 | 02:04:37:893PM | Plasma | Ok | |
| 21 | 02:21:51:720PM | Plasma | Ok | |
| 22 | 02:37:09:243PM | Plasma | Ok | |
| 23 | 02:53:31:280PM | Plasma | Ok | |
| 24 | 03:14:59:040PM | Plasma | Ok | |
| 25 | 03:30:13:200PM | Plasma | Ok | |
| 26 | 03:45:27:970PM | Plasma | Ok | |
| 27 | 04:00:44:847PM | Plasma | Ok | |
| 28 | 04:13:04:190PM | Plasma | Ok | |
| 29 | 04:25:31:793PM | Plasma | Ok | |
| 30 | 04:40:23:897PM | Plasma | Ok | |
| 31 | 04:54:51:920PM | Plasma | Ok | |
| System Availability | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
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