| Miniproposals | ||||||||||
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| Operators | |
| Session leader(s): | Steve Wolfe |
| Physics operator(s): | Ron Parker |
| Engineering operator(s): | Ed Fitzgerald,Gary Dekow |
| Engineering Operator Run Comment |
| Continuation of MP 298A, SL: Wolfe, PO: Parker, EO: Dekow/Fitzgerald |
| Session Leader Plans |
| Physics Operators Plans |
| Session Leader Summaries |
| Physics Operator Summaries |
| Entered: Jul 7 2004 04:37:14:897PM |
| Author: To Be Determined |
| Physop Summary for Run 1020621 Engineering Setup for FRIDAY, JUNE 21, 2002 Continuation of MP 298A SL: Wolfe PO: Parker ECDC in D2 overnight, stopping 2 hours before the run Run Begins at 9:00 and ends at 17:00 Power systems setup the same as for Shot 1020620002 Gas setup: B-Top 6 psi D2 Hybrid Enabled (PG4) B-side lower 1 psi Ar Hybrid Enabled (PG1) B-side upper 10 psi D2 Hybrid DISABLED (PG2, for ECDC) C-Side 30 psi D2 Hybrid Enabled (PG3) J-Bottom leave as is Enable the following gate valves, assuming no vacuum problems: ECE, DNB RF Setup: None RUN PLAN: We'll continue startup/cleanup efforts Run Summary The objective was to continue startup and cleanup discharges. The first shot after two power test shots was loaded from the previous day and it ran perfectly. But then began a series of 9 shots which were either fizzles or duds. As usual, each shot, or non-shot, was followed by a number of small tweaks to the Bv, BR or fill pressure. Finally, Shot 13 again ran perfectly. No obvious cause for the difficulty or for the unexpected success on shot 13 could be identified. Once again there ensued a spate of duds and fizzles. It was suspected that perhaps the shot had to end in 3 in order for it to run, but this did not prove to be the case as shot 23 was a dud. Finally, in desperation, a small amount of argon was added to the prefill, the idea being that this would facilitate breakdown if not startup. Somewhat surprisingly, it worked! Shot 25 again ran perfectly. Unfortunately this was the last shot of the day so the breakdown-startup problem could not be pursued further. Clearly this was a very frustrating run with only 3 shots produced. The other 20 shots were either duds (8) or fizzles (12). Peculiar is that the machine ran very well when the discharge "went". This would suggest that there is nothing fundamentally wrong with the internals. One would expect a certain amount of trouble with succesive shots if the machine is still dirty, which it probably is. But this would not explain the duds, unless some electron attaching gas was produced. Also curious is that the fill pressure for breakdown had to be relatively high,just over 1.e-4 T. The funtioning of the sparker was called into question. It is not clear as of this writing if the sparker was or was not functioning properly. It is in process of being checked and should be available for the next run. Meanwhile, the argon trick could be also exploited as a backup or supplement. The argon injected on shot 25 was quite small, the fill pressure being 1 psi, compared to 6 psi of D2. The same pulse width (40 ms) was used for the two valves. |
| Session Leader Comments | |||
| Jun 21 2002 10:07:40:120AM | 1020621003 | Jim Irby | Very nice shot --- reload from last shot from yesterday Still very high fill H/D less than 30% during most of shot Gas puff required to control density at a higher level than yesterday Next shot Ron will reduce NL04 request to 5e19 from 7e19 /m^2 |
| Jun 21 2002 10:13:58:720AM | 1020621004 | Jim Irby | Fizzle Carbon II level.005 --- not bad |
| Jun 21 2002 10:53:10:200AM | 1020621005 | Jim Irby | 10 minutes of ECDC at 2e-4 Torr D2 before shot --- bp at 1.1e-6 Torr before shot Fizzle |
| Jun 21 2002 11:37:29:860AM | 1020621006 | Jim Irby | No ECDC Dud |
| Jun 21 2002 11:38:03:580AM | 1020621007 | Jim Irby | 10 minutes ECDC Dud |
| Jun 21 2002 11:38:36:470AM | 1020621008 | Jim Irby | ECDC Dud |
| Jun 21 2002 12:47:54:607PM | 1020621011 | Jim Irby | Dud |
| Jun 21 2002 01:47:55:970PM | 1020621012 | Jim Irby | Jim's new camera at f-hor see first light. Very late breakdown, 14 ms, with very little light seen on CII. |
| Jun 21 2002 01:54:54:770PM | 1020621013 | Jim Irby | Nice plasma No density control (at 5e19/m^2 request) H/D 25% CII .006 |
| Jun 21 2002 01:52:38:520PM | 1020621014 | Jim Irby | Fizzle |
| Jun 21 2002 02:17:14:187PM | 1020621015 | Jim Irby | Dud Ron will be going the other way on Bz0 |
| Jun 21 2002 03:07:50:860PM | 1020621017 | Jim Irby | Dud |
| Jun 21 2002 04:13:55:200PM | 1020621018 | Jim Irby | Dud |
| Physics Operator Comments | |||
| Jun 21 2002 09:51:22:867AM | 1020621002 | Ron Parker | Plan for this run is to continue conditioning of machine. Run start was delayed due to repair of OH2 Lower power supply, which had faulted during the 1020620 run. Shots 1 and 2 were test shots. |
| Jun 21 2002 10:12:37:827AM | 1020621003 | Ron Parker | This shot ran well. Due to operator error, the last shot from 1020620 was setup. This was a nearly double null shot. |
| Jun 21 2002 10:35:20:523AM | 1020621004 | Ron Parker | Shot 4 was a fizzle. This shot had been set up the same as shot 1020620009, but with the density programmed waveform set at 0.5e20 m-3. In the next shot, the inital settings will be the same as in shot 1020621003, again with density at 0.5e20 m-3. |
| Jun 21 2002 10:40:38:337AM | 1020621005 | Ron Parker | Shot 5 was also a fizzle. |
| Jun 21 2002 11:05:21:957AM | 1020621006 | Ron Parker | Shot 6 was a dud. The fill pressure will be increased for the next shot. |
| Jun 21 2002 11:21:42:917AM | 1020621007 | Ron Parker | Shot 7 was also a dud. Fill pressure was .09 mT. Stray fields look fine. Next shot: Fill lowered to .07 mT. |
| Jun 21 2002 11:36:52:593AM | 1020621008 | Ron Parker | Shot 8 was another dud. Bz has become slightly positive at 5 ms. For next shot, we'll decrease EF4 current by 20 A (to -1340 A). |
| Jun 21 2002 11:53:55:397AM | 1020621009 | Ron Parker | Shot 9 was another dud. The trimming of EF 4 curent by -20 A had the desired effect -- BZ decreased by 1 mT. Both stray fields are in the good breakdown/ startup range according to Jim's histogram. For the next shot the pressure will be increased, to ~ 0.1 mT. |
| Jun 21 2002 12:19:11:000PM | 1020621010 | Ron Parker | Progress! Shot 10 was a fizzle, with the current reaching about 40 kA. The fill pressure was 0.1 mT, quite high for normal operation. Stray fields still seem to be well within the optimum ranges according to Jim's histogram. JT is installing an H alpha camera to get better view in the machine during ECCD. |
| Jun 21 2002 12:42:20:510PM | 1020621011 | Ron Parker | Shot 11 was a dud, same conditions as 10. ECDC will be turned on to view inside vessel with JT's camera. |
| Jun 21 2002 01:29:46:153PM | 1020621012 | Ron Parker | Shot 12 was a peculiar fizzle, late breakdown ~ 15 ms. No sign of protusions from the camera. Bz at breakdown ~ 3 mT. Next: Repeat shot with BR reduced from 1.5 to 1.0 mT. |
| Jun 21 2002 01:45:03:453PM | 1020621013 | Ron Parker | Shot 13 actually ran! Bz(0) was ~ +1 mT (most shots until this one had slightly negative Bz. Also BR ~ - 1.25 mT (by design) |
| Jun 21 2002 01:55:13:070PM | 1020621014 | Ron Parker | Shot 14 was a fizzle. Bz was slightly less by ~ 1mT than in previous shot. Bz will be increased by 1 mT for shot 15. |
| Jun 21 2002 02:29:10:470PM | 1020621015 | Ron Parker | Shot 15 was a dud -- so much for the higher Bz cure. On the next shot, we'll go the other way on Bz to bracket the range of Bz for which we get breakdown. |
| Jun 21 2002 02:39:20:897PM | 1020621016 | Ron Parker | Shot 16 was a dud. EF 4 was set at 1360. We'll go back to the settings in the last shot that ran, shot 13. |
| Jun 21 2002 02:59:49:077PM | 1020621017 | Ron Parker | Shot 17 was another dud. The stray fields are very nearly identical to those in shot 13, which ran. It doesn't look like the stray fields are the issue. We'll start a pressure scan, beginning at ~ 0.05 mT with shot 18. |
| Jun 21 2002 03:13:45:350PM | 1020621018 | Ron Parker | Shot 18 was a dud. The fill pressure had been reduced to 0.05 mT. For shot 19 the fill pressure will be set at ~ 0.075 mT. |
| Jun 21 2002 03:30:15:480PM | 1020621019 | Ron Parker | Shot 19 was another dud. The pressure will be set back to the value in shot 013, i.e., 0.1 mT. |
| Jun 21 2002 03:49:22:003PM | 1020621020 | Ron Parker | At last, a fizzle! Back to 0.1 mT. For the next shot, we'll continue to increase the pressure. The next setting will be 0.12 mT. |
| Jun 21 2002 04:13:12:307PM | 1020621021 | Ron Parker | Shot 21 was a very late breakdown fizzle. Fill pressure was ~0.12 mT Next shot, fill pressure will be ~0.11 mT |
| Jun 21 2002 04:31:22:840PM | 1020621022 | Ron Parker | Shot 22 again fizzled with late breakdown. For next shot, gas set back to 40 ms and BR(0) set at .0005. |
| Jun 21 2002 04:54:07:917PM | 1020621023 | Ron Parker | Shot 23 was a dud. For the next to last "shot", we'll reload segment 1 from the last successful shot, shot 13. |
| Jun 21 2002 04:58:19:400PM | 1020621024 | Ron Parker | Shot 24 was another dud. We'll try a last shot with Ar added to the prefill to help breakdown. Same waveform for Ar valve as used for the D2 prefill. |
| Jun 21 2002 05:07:00:493PM | 1020621025 | Ron Parker | Shot 25 went! Ar help? Sparker working? ECDC off? Tune in next week! |
| Engineering Operator Comments | ||||
| Shot | Time | Type | Status | Comment |
| 1 | 09:08:28:427AM | Test | Ok | Cycle Test |
| 2 | 09:37:44:987AM | Test | Ok | OH Supplies and Commutation Test |
| 3 | 09:51:31:537AM | Plasma | Ok | |
| 4 | 10:06:42:263AM | Plasma | Ok | |
| 5 | 10:36:18:053AM | Plasma | Ok | |
| 6 | 10:51:47:153AM | Plasma | Ok | |
| 7 | 11:09:07:537AM | Plasma | Ok | |
| 8 | 11:29:06:683AM | Plasma | Ok | |
| 9 | 11:42:18:393AM | Plasma | Ok | |
| 10 | 12:04:43:057PM | Plasma | Ok | |
| 11 | 12:35:00:537PM | Plasma | Ok | |
| 12 | 01:05:20:503PM | Plasma | Ok | |
| 13 | 01:27:36:120PM | Plasma | Ok | |
| 14 | 01:47:54:080PM | Plasma | Ok | |
| 15 | 02:06:56:433PM | Plasma | Ok | |
| 16 | 02:28:40:893PM | Plasma | Ok | |
| 17 | 02:47:23:730PM | Plasma | Ok | |
| 18 | 03:05:53:313PM | Plasma | Ok | |
| 19 | 03:23:21:320PM | Plasma | Ok | |
| 20 | 03:40:58:267PM | Plasma | Ok | |
| 21 | 03:58:53:350PM | Plasma | Ok | |
| 22 | 04:20:22:893PM | Plasma | Ok | |
| 23 | 04:37:59:050PM | Plasma | Ok | |
| 24 | 04:50:30:407PM | Plasma | Ok | |
| 25 | 05:04:03:903PM | Plasma | Ok | |