| Miniproposals | ||||||||||||
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| Operators | |
| Session leader(s): | Steve Golovato,Yuichi Takase |
| Physics operator(s): | Earl Marmar |
| Engineering operator(s): | Joe Daigle,Vinny Bertolino |
| Engineering Operator Run Comment |
| 3He 2'nd harmonic heating at 4T |
| Session Leader Plans |
| Physics Operators Plans |
| Session Leader Summaries |
| Entered: Jul 7 2004 03:49:13:790PM |
| Author: To Be Determined |
| Run 950525 Day 2 of He3 2nd harmonic minority (or majority) heating SL: Takase PO: Marmar EO: Bertolino/Daigle The original objective of demonstrating the He3 2nd harmonic heating was not achieved, but the run was used effectively to obtain useful data on several other topics. He3 2nd harmonic minority (or majority) heating ----------------------------------------------- We have tried to push the H resonance out of the plasma by lowering the toroidal field. Because the breakdown was at 3.5T during the TF ramp we settled for 3.6T which places the H resonance outside the plasma, but still inside the vessel near the inner wall (3.4T would have been better). The plasma was very dirty, which seemed to correlate with the amount of He3 puffed. After shot 09 we abandoned He3 2nd harmonic heating and ran a number of "clean-up" shots at 5.3T. We tried to determine if the problem was with contaminated He3 or with poor single-pass absorption combined with edge H resonance (at 3.5-4T) or edge He3 resonance (at 5.3T). The result was not conclusive, He3 majority H minority heating ------------------------------- After getting the plasma back, we moved to 5.3T breakdown on shot 23. At this field He3 resonance is near the inner wall. We tried to shift the resonance by going up to 5.8T and then down to 5T (5T should be better because it shifts the resonance beyond the inner wall). We observed both electron and ion heating on shot 29, but this shot had mostly D with some He3. The attempt to increase the He3 concentration on shot 30 was unsuccessful, resulting in a huge density rise followed by a disruption (there is still a 2nd harmonic He3 resonance on the low field side). H 2nd harmonic minority heating at 2.6T --------------------------------------- This is the standard heating scenario in JT-60U, and is supposed to work. Without the presence of He3 the resonance geometry is much cleaner. Because it would require serious discharge development, this was achieved by ramping down the TF. We got reasonable heating on shot 36 with 2.7MW of RF power, but the power deposition zone is continuously changing because of the TF ramp. At least we have confirmed that there is a heating scenario at low field with the 80MHz transmitter. At 4T, serious wall conditioning (like boronization) is probably required to make it work. PEP mode -------- The remainder of the run (shots 37-42) was spent exploring the PEP mode. We had both Li pellet problems and RF coupling problems and did not really do better than 950120016 (9X10^13 neuts/sec). Shot 39 was a 0.8 MA H-mode with P_RF = 2.5 MW and W_EFIT = 100kJ. Shot 42 was a 1 MA PEP mode with P_RF = 2.2 MW, 3X10^13 neuts/sec, and W_EFIT = 107 kJ. shot 01 test Starting from shot 950524010. 02 fiz Trying to get plasma at 4T, 0.6MA, nel_04=0.8, very little He3. 03 pla disrupted @ 1.0sec 04 pla 3.6T, 0.6MA, very little He3, E-port transmitter tripped 05 pla 3.6T, 50-50 D-He3 mixture (both on nel feedback) 06 pla more He3 (only voltage prog) 07 pla all He3, disrupted at 0.36s plasma very dirty, trying to clean up over the next few shots 08 pla no He3, disrupted at 0.18s 09 pla no He3, disrupted at 0.53s (ugly shot) 10 pla no He3, no RF, BT=5.3T (breakdown still at 3.5T), better shot 11 pla no He3, RF on, 5.3T, getting better 12 pla He3 on, no RF 13 pla He3 on, disrupt @ 0.63s 14 pla He3 off, RF on 15 dud another cleanup shot, no He3, RF on, gpc retuned to 5.3T, no TF 16 pla no He3, RF on, still cleaning up 17 pla 0.8MA, nel_04=1.0, no He3, RF on 18 fiz He3 on, RF off 19 pla He3 on (100% after 0.5s), RF off, higher dens (nel=1.4) 20 pla repeat, OK He3 majority, H minority 21 fiz He3 on, RF on 22 fiz 23 pla 5.3T breakdown from 950523010, He3 on, RF on, not much heating 24 pla more He3, large density rise, disrupt @ 0.75s He3 resonance is on the inner wall (2nd harmonic near antenna) 25 pla 5.8T 26 pla TF rampdown (want 5.1T @ 0.71s), disrupt @ 0.43s 27 pla lower nel to 1.0, TF rampdown, heating shifts off-axis 28 dud breakdown @ 5.0T, no TF 29 pla 5.0T, He3 resonance pushed out, more D than He3, e & i heating 30 pla same, more He3, density rise and disruption @ 0.78s 31 pla TF rampdown to 2.5T @ 1sec (4T/sec), no He3, enable H puff from B top 32 dud more H puff 33 pla disrupt @ 0.52s 34 pla TF rampdown starting from 5.3T, some heating 35 pla better heating 36 pla 2.7MW, better heating PEP mode with Li pellet (50msec before RF) @ 5.6T, 0.9MA, nel=1.2 37 pla no pellet, no RF 38 pla no pellet, got RF (3 H-modes) 39 pla no pellet, higher power RF, 100kJ 40 pla got pellet, E-port started late 41 pla delay pellet by 20msec, disrupt @ 0.84s 42 pla 1MA E-port tripping, PEP mode (3X10^13 neuts/sec) |
| Physics Operator Summaries |
| Entered: Jul 7 2004 04:36:54:520PM |
| Author: To Be Determined |
| 950525 continuation of MP 115A, 2'nd harmonic 3He heating PO Marmar SL Takase/Golovato EO Bertolino/Daigle We explored a fair amount of territory today. See Takase's run summary for the RF results. We ran into problems with dirt early in the day, similar to some of yesterday's problems. My conclusion is that this was due to "heating" with a resonance at or near the edge of the plasma. All such cases lead to decreases in stored energy, much radiated power, and degradation of the current and density rises on subsequent shots. During ramp down to low field (<2.5T) we consistently disrupted around q_95=2. These shots should be interesting for the disruption data base, since they had large Ihalo/Iplasma ratios. After exploring all the 3He scenarios that the RF group could think of, the last 1.5 hours of the run was devoted to ICRF H-modes and PEP modes. There were two no-TF duds; otherwise the power systems ran well, and the shot cycle was generally limited by PO/SL think time. Note to operators: Steve Wolfe modified the tree so that the pulsed gas voltage waveforms can be programmed negative, if desired; this allows you to turn off the valve that was used for fill at any time during the shot, by programming a negative voltage whose absolute value is greater than the voltage used for fill. Start from 950524010, but .6MA and less He3 1 test 2 Pfill=1.8e-5, fizzle 3 lower B_r offset by .5mT, plasma, disrupt at end of flat-top, just after RF turn-off 4 lower B_T to 100kA (3.63 T), good shot 5 go to ~50/50 3He/D puff, using double feedback on nl_04, plasma, disrupt at .8s, during RF 6 switch to all 3He puff on the feedback, disrupt at .8 s 7 turn off D2 puff at .3 s, ugly shot, disrupt at .33 s 8 much less He3, looks even worse,disrupt at .17 s 9 He3 off, very ugly, but lasted a little longer 10 TF ramp up to 5.4 tesla, still breakdown at 3.5, no RF, better, but still dirty early, decent shot after .4s 11 retry, with RF, still 5.4 T, no He3, good shot, RF heating 12 back to 100% He3 puffing after .5 s, tree modified (by Steve Wolfe) to allow negative voltages on the pulsed gas programming, no RF, good shot, although early density rise was a little ragged. 13 repeat, Argon enabled, RF back on, ugly shot, disrupt at .6 s 14 He3 off, argon off, good shot, still ragged during current rise 15 repeat, no TF, dud 16 lower early pulse gas slightly, good shot, but still a little lumpy on the rise 17 800 kA, 1e20, good shot, h-mode during RF 18 switch to He3 again after .5 s, nl_04=1.2e20, no RF, fizzle 19 P_fill=2e-5, good shot, lumpy during rise, shark fin disrupt on rampdown at 1.3 s, .3MA 20 repeat, good shot, but density rise looks peculiar, also dirty early, disrupt late 21 RF back on, fizzle 22 lower B_R offset by .5 mT, fizzle 23 go to 5.3 tesla breakdown, change resistors, load segment 1 from 950523010, lower B_R offset by .5mT, good shot, poor RF heating 24 switch to He3 at .4 s, disrupt at .75 s, big density rise after RF turn-on 25 raise B_T to 5.8 tesla, disrupt at .75 s 26 back to 5.3 tesla, TF invert at .625, nl_04 1.1e20, disrupt at .44 seconds 27 lower nl_04 to 1e20, move He3 puff to .6 s, made it to .3MA on rampdown 28 5 Tesla, TF invert at 1.0, no TF, dud 29 retry, good plasma, ramped down to .2MA, 30 move He3 to start at .4 s, a little more argon, good 31 TF rampdown start at .375, to get to 2.5 T at 1 second, no He3, D2 majority, H2 puff from B-top (voltage programmed), disrupt at 1.1 s; got 2 T at 1 s, q_95=2 at disruption 32 increase H2 voltage (from 32 to 40V), dud! 33 B_R offset decrease by .5mT, disrupt at .52 34 B_T back up 5.3 T at breakdown, lower H2 valve voltage to 34 V, good 35 repeat, good, halo warning 36 repeat good, halo warning 37 go to 5.6 tesla straight across, PEP mode, no pellet, no RF, good shot 38 RF, but no pellet 39 RF, but no pellet 40 Got pellet(.805) and RF, but E-port came on late 41 delay pellet 20 ms, prompt disruption after pellet, Darren says it was a double pellet 42 Ip 1 MA, nl_04=1.2e20, short pep mode, one antenna tripping, good plasma. Summary: 41 plasma attempts, 34 plasmas, 4 fizzles, 3 duds |
| Session Leader Comments | |||
| May 25 1995 08:39:02:820AM | 950525001 | Yuichi Takase | Day 2 of He3 2nd harmonic minority (or majority) heating
Shot 01 - test |
| May 25 1995 08:44:08:770AM | 950525002 | Yuichi Takase | Starting from shot 950524010.
Trying to get plasma at 4T, 0.6MA, nel_04=0.8, very little He3. Shot 02 - fizzle |
| May 25 1995 12:34:38:080PM | 950525003 | Yuichi Takase | Shot 03 - plasma
disrupted @ 1.0sec |
| May 25 1995 12:34:56:030PM | 950525004 | Yuichi Takase | Shot 04 - plasma
3.6T, 0.6MA, very little He3, E-port transmitter tripped |
| May 25 1995 12:35:14:840PM | 950525005 | Yuichi Takase | Shot 05 - plasma
3.6T, 50-50 D-He3 mixture (both on nel feedback) |
| May 25 1995 12:35:54:860PM | 950525006 | Yuichi Takase | Shot 06 - plasma
more He3 (only voltage prog) |
| May 25 1995 01:16:50:910PM | 950525007 | Yuichi Takase | Shot 07 - plasma
all He3, disrupted at 0.36s plasma very dirty, trying to clean up over the next few shots |
| May 25 1995 01:17:08:540PM | 950525008 | Yuichi Takase | Shot 08 - plasma
no He3, disrupted at 0.18s |
| May 25 1995 01:17:25:380PM | 950525009 | Yuichi Takase | Shot 09 - plasma
no He3, disrupted at 0.53s (ugly shot) |
| May 25 1995 01:17:52:960PM | 950525010 | Yuichi Takase | Shot 10 - plasma
no He3, no RF, BT=5.3T (breakdown still at 3.5T), better shot |
| May 25 1995 01:18:12:190PM | 950525011 | Yuichi Takase | Shot 11 - plasma
no He3, RF on, 5.3T, getting better |
| May 25 1995 01:18:30:470PM | 950525012 | Yuichi Takase | Shot 12 - plasma
He3 on, no RF |
| May 25 1995 01:20:37:250PM | 950525013 | Yuichi Takase | Shot 13 - plasma
He3 on, disrupt @ 0.63s |
| May 25 1995 01:21:00:200PM | 950525014 | Yuichi Takase | Shot 14 - plasma
He3 off, RF on |
| May 25 1995 01:21:30:510PM | 950525015 | Yuichi Takase | Shot 15 - dud
another cleanup shot, no He3, RF on, gpc retuned to 5.3T, no TF |
| May 25 1995 01:24:26:130PM | 950525016 | Yuichi Takase | Shot 16 - plasma
no He3, RF on, still cleaning up |
| May 25 1995 01:24:44:560PM | 950525017 | Yuichi Takase | Shot 17 - plasma
0.8MA, nel_04=1.0, no He3, RF on |
| May 25 1995 01:25:10:850PM | 950525018 | Yuichi Takase | Shot 18 - fizzle
He3 on, RF off |
| May 25 1995 01:25:33:840PM | 950525019 | Yuichi Takase | Shot 19 - plasma
He3 on (100% after 0.5s), RF off, higher dens (nel=1.4) |
| May 25 1995 01:26:00:280PM | 950525020 | Yuichi Takase | Shot 20 - plasma
repeat, OK He3 majority, H minority |
| May 25 1995 01:26:24:190PM | 950525021 | Yuichi Takase | Shot 21 - fizzle
He3 on, RF on |
| May 25 1995 01:26:38:950PM | 950525022 | Yuichi Takase | Shot 22 - fizzle
|
| May 25 1995 01:27:02:200PM | 950525023 | Yuichi Takase | Shot 23 - plasma
5.3T breakdown from 950523010, He3 on, RF on, not much heating |
| May 25 1995 01:27:26:360PM | 950525024 | Yuichi Takase | Shot 24 - plasma
more He3, large density rise, disrupt @ 0.75s He3 resonance is on the inner wall (2nd harmonic near antenna) |
| May 25 1995 01:28:15:130PM | 950525025 | Yuichi Takase | Shot 25 - plasma
5.8T, same, large density rise and disruption |
| May 25 1995 01:28:38:130PM | 950525026 | Yuichi Takase | Shot 26 - plasma
TF rampdown (want 5.1T @ 0.71s), disrupt @ 0.43s |
| May 25 1995 01:43:11:560PM | 950525027 | Yuichi Takase | Shot 27 - plasma
lower nel to 1.0, TF rampdown, heating shifts off-axis |
| May 25 1995 01:43:44:680PM | 950525028 | Yuichi Takase | Shot 28 - dud
breakdown @ 5.0T, no TF |
| May 26 1995 11:13:43:460AM | 950525029 | Yuichi Takase | Shot 29 - plasma
5.0T, He3 resonance pushed out, more D than He3, e & i heating |
| May 26 1995 11:14:49:220AM | 950525030 | Yuichi Takase | Shot 30 - plasma
same, more He3, density rise and disruption @ 0.78s |
| May 26 1995 11:15:08:180AM | 950525031 | Yuichi Takase | Shot 31 - plasma
TF rampdown to 2.5T @ 1sec (4T/sec), no He3, enable H puff from B top |
| May 26 1995 11:15:33:840AM | 950525032 | Yuichi Takase | Shot 32 - dud
more H puff |
| May 26 1995 11:16:33:970AM | 950525033 | Yuichi Takase | Shot 33 - plasma
disrupt @ 0.52s |
| May 26 1995 11:16:52:900AM | 950525034 | Yuichi Takase | Shot 34 - plasma
TF rampdown starting from 5.3T, some heating |
| May 26 1995 11:17:47:790AM | 950525035 | Yuichi Takase | Shot 35 - plasma
better heatin |
| May 26 1995 11:18:08:120AM | 950525036 | Yuichi Takase | Shot 36 - plasma
2.7MW, better heating |
| May 26 1995 11:19:25:760AM | 950525037 | Yuichi Takase | Shot 37 - plasma
PEP mode with Li pellet (50msec before RF) @ 5.6T, 0.9MA, nel=1.2 no pellet, no R |
| May 26 1995 11:19:45:730AM | 950525038 | Yuichi Takase | Shot 38 - plasma
no pellet, got RF (3 H-modes) |
| May 26 1995 11:20:09:990AM | 950525039 | Yuichi Takase | Shot 39 - plasma
no pellet, higher power RF, 100kJ |
| May 26 1995 11:20:49:650AM | 950525040 | Yuichi Takase | Shot 40 - plasma
got pellet, E-port started late |
| May 26 1995 11:21:05:890AM | 950525041 | Yuichi Takase | Shot 41 - plasma
delay pellet by 20msec, disrupt @ 0.84s |
| May 26 1995 11:21:43:320AM | 950525042 | Yuichi Takase | Shot 42 - plasma
1MA E-port tripping PEP mode (3X10^13 neuts/sec) |
| Physics Operator Comments |
| Engineering Operator Comments | ||||
| Shot | Time | Type | Status | Comment |
| 1 | 07:49:28:370AM | Test | Ok | data test |
| 2 | 08:32:49:720AM | Plasma | Ok | |
| 3 | 08:43:32:420AM | Plasma | Ok | |
| 4 | 08:56:01:290AM | Plasma | Ok | |
| 5 | 09:09:17:550AM | Plasma | Ok | |
| 6 | 09:23:52:870AM | Plasma | Ok | |
| 7 | 09:34:41:840AM | Plasma | Ok | |
| 8 | 09:48:37:880AM | Plasma | Ok | |
| 9 | 09:58:48:220AM | Plasma | Ok | oh2u comm fault after fizzle |
| 10 | 10:11:26:640AM | Plasma | Ok | |
| 11 | 10:20:39:350AM | Plasma | Ok | |
| 12 | 10:34:43:140AM | Plasma | Ok | |
| 13 | 10:47:08:490AM | Plasma | Ok | |
| 14 | 10:57:34:030AM | Plasma | Ok | |
| 15 | 11:09:02:700AM | Plasma | Bad | no tf |
| 16 | 11:16:47:340AM | Plasma | Ok | |
| 17 | 11:28:36:670AM | Plasma | Ok | |
| 18 | 11:40:22:060AM | Plasma | Ok | |
| 19 | 11:51:52:290AM | Plasma | Ok | |
| 20 | 12:01:35:430PM | Plasma | Ok | |
| 21 | 12:12:01:440PM | Plasma | Ok | |
| 22 | 12:20:52:000PM | Plasma | Ok | |
| 23 | 12:34:03:870PM | Plasma | Ok | |
| 24 | 12:47:50:860PM | Plasma | Ok | |
| 25 | 01:02:42:540PM | Plasma | Ok | No Faults |
| 26 | 01:16:13:750PM | Plasma | Ok | |
| 27 | 01:27:29:420PM | Plasma | Ok | |
| 28 | 01:41:10:340PM | Plasma | Ok | |
| 29 | 01:49:43:500PM | Plasma | Ok | |
| 30 | 02:05:37:340PM | Plasma | Ok | |
| 31 | 02:34:29:160PM | Plasma | Ok | |
| 32 | 02:45:54:100PM | Plasma | Ok | |
| 33 | 02:55:34:560PM | Plasma | Ok | no faults |
| 34 | 03:05:39:040PM | Plasma | Ok | |
| 35 | 03:18:44:930PM | Plasma | Ok | |
| 36 | 03:29:32:380PM | Plasma | Ok | |
| 37 | 03:45:06:100PM | Plasma | Ok | |
| 38 | 03:57:36:260PM | Plasma | Ok | |
| 39 | 04:15:33:520PM | Plasma | Ok | |
| 40 | 04:27:03:420PM | Plasma | Ok | |
| 41 | 04:40:37:290PM | Plasma | Ok | |
| 42 | 04:55:17:910PM | Plasma | Ok | |