| Miniproposals | ||||||||||||
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| Operators | |
| Session leader(s): | Bruce Lipschultz,Earl Marmar |
| Physics operator(s): | Steve Wolfe |
| Engineering operator(s): | Bill Cochran,Bill Byford |
| Engineering Operator Run Comment |
| MP430 - Between shot boronization |
| Session Leader Plans |
| Entered: Aug 8 2005 06:06:05:953PM |
| Author: Bruce Lipschultz |
| MP430 - Between shot boronization
Normal overnight cleaning procedure: I am not sure whether we are doing ECDC or not in the am, no preference on my part. Assume 15 minute boronization length to start with. Pressure 5 mT (standard?). Pause at center of each scan. Note - We will be using the new 20% diborane 80% He mixture which has twice the amount of diborane as usual. Dream up different ways to reduce fizzles after boronization (e.g. wait longer, ECDC in He after the diboarne....) 1) Take 1-2 shots - 1050805019 is fine. Basically our 1 MA standard shot. This will be the un-boronized background 2) Boronize between shots with scan width of 25 cm (inner edge 70 cm). Take 2 shots to ascertain the effect. Make sure the last shot returns to shot in step 1. 3) Boronize between shots with scan width of 25 cm (inner edge 45 cm). Take 2 shots to ascertain the effect. Make sure the last shot returns to shot in step 1. 4) Decide which of the above scan regions is better and go to next step. 5) Boronize sequence (1 shot to measure effect, 2nd shot to determine if it has worn off) using 10 cm wide scans to cover the better 25 cm region selected above. Work from outer major radius inward in 5 cm steps. (10 shots minimum not including fizzles) 6) Once done with the scan, return to the most effective location. Vary the pressure during the boronization below the usual value to 1 mTorr and 0.5 mTorr. If there is an effect explore it (4 shots min, not including fizzles). 7) Compare the usual boronization including pulsed ECDC with leaving the ECDC on steadily during the period. 8) If not done earlier then reduce the length of boronizations now to 10 and 5 minutes length (4 shots min. if not including fizzles). |
| Physics Operators Plans |
| Entered: Aug 8 2005 05:30:47:263PM |
| Author: Steve Wolfe |
Engineering setup and Physop plan for Tuesday, August 9, 2005 MP#430 Localization of the effect of boronization SL: Lipschultz PO: wolfe Run begins 09:00 and ends 17:00 (with option to extend to 19:00) No overnight ECDC, bake at 60C Depending on results, we may decide either to extend the run to 19:00 or to do an overnight boronization after completing the run at 17:00. **************************************************************************** This run will use between-shot boronization. No Non-emergency access to cell or power room once the diborane bottle is opened. **************************************************************************** We will want one successful data system cycle before the diborane bottle is opened, in case a crate needs to be power-cycled in the cell or power room. The test cycle should probably be done as early as possible, before lockup. At the request of the SL, I will need to turn on his calibration lamp in the cell before lockup. Engineering setup: ------------------- Power systems as on 1050705022 A-coil in standard configuration: +Dtop -Dbot -Jtop +Jbot, C-coil Start=0.3sec, Invert=2.0sec ICRF in Run-on by 08:30AM Gas Setup: ---------- fill B-top 6psi D2 Hybrid Enabled (PG4) fill B-side lower 1psi Argon+2psi neon Hybrid Disabled (PG1) leave B-side Upper alone (15psi He3) Hybrid Enabled (PG2) fill B-main 40psi D2 Hybrid Enabled (PG3) NINJA: 10psi D2 Boronization system set up for between-shot boronization Enable ECE, VUV, Z-bolo shutter for all plasma shots; these must be disabled for between-shot boronization The A-Side TV camera shutter must be CLOSED before the start of the run, and remain closed throughout the day. The wide1 TV view will not be available for this run. The MSE shutter must be CLOSED before the start of the run, and remain closed throughout the day. PCS Setup: --------- Load Seg2 from 1050705018 (Best shot of 1050705) and set He3 puff (PG2) to 100ms starting at 0.2 sec. Tweak startup to taste. Run Plan: --------- Follow SL's instructions on boronization times and scans. The present plan is 1) We'll be starting with one or two shots with no boronization. 2) Boronize at standard pressure for 15 minutes with scan 70/83/95, then take two shots 3) Boronize at standard pressure for 15 minutes with scan 45/56/70, then take two shots 4) Boronization sequence with 10cm wide scans at 5cm intervals to test for best location. 5) At best location found, vary boronization pressure and try to optimize. 6) If time permits, vary boronization duration (reduce) and optimize. After each boronization, try allowing torus pressure to come down to 2e-6 before INIT to see if it helps prevent fizzles. Other tweaks to try include RCUR offset to 1000 and IC_EF4 up and down by 15 amps or so. RF should try for 0.9sec (0.6 to 1.5sec) pulse at Prf~3MW (combined J and E), unless SL_PLAN says something different. |
| Session Leader Summaries |
| Entered: Aug 9 2005 02:45:54:340PM |
| Author: Bruce Lipschultz |
| MP430 - optimization of between shot boronization
Very little of the plan was accomplished. The run was plagued by problems right from the beginning - problems with the boronization scan limits, the Thomson, the McPherson spectrometer.. We had more difficulty than the previous day dedicated to this study (1050705) with the fact that we had 2 fizzles after each boronization (except for the last try). Lastly we lost the E antenna transmitter and that left us with inadequate heating. My impression is that we did not reach stored energy levels equivalent to 1050705. This could be due to differences in boronization (15 minutes as opposed to 30 minutes, 20% as opposed 10% diborane in the boronization gas), or differences in the heating efficiency of J with 50 MHz. Based on shot 14 where the plasma did not enter H-mode until almost the end of the RF pulse at 2.5 MW it appears that the RF heating efficiency is the reason. We did find that after the inner scan (45-70 cm, shot 14) the midplane and divertor pressures pre-H-mode and during H-mode were higher by 30-50% than earlier shots (e.g. 11). These pressures came back down on the following shot. This is either due to the boronization scan range or the fact that we only had 1 fizzle before the shot. Since the last sequence of shots after a boronization resulted in only one fizzle it is hoped that we can reproduce this tomorrow. We could also try to ECDC with He after the boronization (before a shot) with either a complete scan of the chamber 44-106 cm) or just near the inner wall. We did complete the outer 35 cm scan (70-95 cm). In the continuation of today's run (tomorrow if E antenna transmitter is fixed) we will redo the inner scan (45-70 cm) and continue with the remainder of the shot plan posted for today. |
| Entered: Aug 9 2005 02:52:18:827PM |
| Author: Earl Marmar |
| MP430 Localization of boronization
SL: Lipschultz PO: Wolfe Asst SL: Marmar Today we are using the GA diborane bottle, which has 20% D_2B_6/80%He. We got started on the MP, completing the 15 minute boronization in the outer radii (ECDC scan from 70 to 95 cm, dwell at 83) after shot 8, followed by 2 fizzles. Shot 11 had a decent EDA H-mode, with confinement and neutron production similar to the better shots from 1050705 that were preceded by only 10 minutes of boronization with the lower concentration diborane (10%). A good comparison shot is 1050705016. After this, E-port ran into a crowbar problem. Attempts to get 3 MW from J alone were tried, but because of faulting, we decided to stop the run early to repair E-port. |
| Physics Operator Summaries |
| Entered: Aug 9 2005 03:09:58:373PM |
| Author: Steve Wolfe |
We only got up to step #3 of the run plan before we lost
E-port with a crowbar problem that could not be reset. After
a few attempts to run with J-port only, we shut down the run
so the engineers could work on FMIT#2. We found that the 20%
diborane mix was useable for boronization, and may be more
time-effective, although this is not definite. The main goals
of the run, to identify the optimum location for ecdc boronization
and to solve the problem of fizzles after the between-shot
boronization, were not accomplished. This MP has been tentatively
rescheduled for Wednesday, if the E-port transmitter can be fixed
by then.
The initial boronization (before shot#5) was inadvertently set up
for 44 to 103cm rather than 70 to 95cm. After a couple of fizzles
and two shots, the first of which disrupted, we did the outer half
boronization (70/83/95) before shot#9. We again had to wait through
two fizzles before getting a successful shot with ~165kJ at 3MW on
shot#11. There was some indication that the boronization was degrading
during the shot, and shot#12 was clearly worse, although comparison
is complicated by the fact that FMIT#2 failed before this shot.
We went ahead with the inner boronization (44/56/70), but with only
J-port we could not make a good comparison. Heating efficiency
from J-port did not seem to be as good today as it was last
Thursday.
There was no improvement in the fizzle problem following between
shot boronization today. Waiting for the base pressure to reach
2e-6 did not help, and neither did decreasing the RCUR offset.
Probably not reducing the pre-puff enough was responsible for
the fact that we had two fizzles following each of the first
two boronizations instead of one. Following the fizzle on shot#13,
after the third boronization, I dropped the pre-puff from
21 to 19msec and got a good plasma. Even lower pre-puffs
could be tried, but that was not successful on 1050705.
The one remaining trick that did not get tried today is to ECDC
in Helium after the boronization. I suggest this be tried tomorrow.
We continued to have baseline offsets on BP16_DE, up to .064V. These
do not seem correlated with disruptions. This loop is used in the
control system and not in the equilibrium reconstruction. The only
available replacement is bp16_jk, which is used in EFIT. So far
we have no indication that the offset has caused any control
problems, but it is a concern.
Shortly after the decision was made to shut down the run we
experienced a power glitch which knocked out a number of
systems in the control room and cell. Pcdaqmhd1 was offline
and had to be rebooted. Other crates may have also been affected,
and should be checked.
Scorecard:
----------
Tests 1
Duds 1
Fizzles 5
Plasmas 9
======== ==
Shots 16
|
| Session Leader Comments | |||
| Aug 9 2005 09:12:47:057AM | 1050809002 | Bruce Lipschultz | dud |
| Aug 9 2005 09:34:59:210AM | 1050809003 | Bruce Lipschultz | Plasma 1MA nl04 slightly less than 1 before the RF pulse.
RF trips out quickly but the plasma continues to go into H-mode Ohmically (H~1.4). Must be a very clean plasma. Repeat to get the RF tuned up. |
| Aug 9 2005 10:11:26:543AM | 1050809004 | Earl Marmar | 3 MW RF, ELM-free H-modes, radiated power rising almost linearly to back transitions
H/(H+D) = .04 to .045 Total neutrons (.7 < t < 1.2) = 1.86e12 |
| Aug 9 2005 10:11:42:933AM | 1050809004 | Bruce Lipschultz | Good background shot. RF lasted the prescribed time.
Stored energy 95-100 kJ, RF power 3 MW. dPrad/dt = 7-10 MW/s (based on 2Pi diode without multiplicative factor). H~1. 15 minute between shot boronization started with scan from 70-95 cm, pause at 83 cm. Mistake - new PLC system setup meant they needed to enable the changes. So we got 44-105 scan, pause at 45 cm for 12 minutes. They corrected it then and we got a ferw minutes of the scan we asked for. |
| Aug 9 2005 10:53:30:013AM | 1050809005 | Bruce Lipschultz | Fizzle |
| Aug 9 2005 10:53:58:090AM | 1050809006 | Bruce Lipschultz | delay for resetting the Thomson computer.
fizzle |
| Aug 9 2005 11:15:18:950AM | 1050809007 | Earl Marmar | looked promising during the early H-mode, then big increase in radiated power and disruption
d(Prad)/dt started quite low H/(H+D) ~ .05 to .055 |
| Aug 9 2005 11:18:16:920AM | 1050809007 | Bruce Lipschultz | shot disrupted at 0.95 seconds after a very large 'brick' dropped in. McPherson was off so the brick material is unknown.
Before the disruption the plasma was doing pretty well: dPrad/dt ~ 3.5 Wtot ~ 150 kJ H ~ 1.6 |
| Aug 9 2005 11:26:20:997AM | 1050809008 | Bruce Lipschultz | Full length shot. Boronization mostly worn off. Not as bad as shot 4, but far from shot 7.
Characteristics: dPrad/dt ~ 5-10 MW/s Wtot ~ 111 kJ H ~ 1.1 |
| Aug 9 2005 11:39:28:763AM | 1050809008 | Earl Marmar | full length plasma
Prad is up on entry to first H-mode (compared to shot 7), but lower than on shot 4 3 MW RF, 2 trips H/(H+D) = .045 Total neutrons (.7 < t < 1.2) = 4.0e12 |
| Aug 9 2005 12:04:41:263PM | 1050809009 | Bruce Lipschultz | fizzle |
| Aug 9 2005 12:04:46:543PM | 1050809010 | Bruce Lipschultz | fizzle |
| Aug 9 2005 12:27:43:200PM | 1050809011 | Bruce Lipschultz | shot fine.
boronization seemed to wear off before the end of the RF pulse as the radiated power was increasing. dPrad/dt ~ 2.0 Wtot ~ 163 kJ H ~ 1.5 Neut rate max - 30e12 take another to make sure it is worn off |
| Aug 9 2005 12:54:43:560PM | 1050809012 | Bruce Lipschultz | 2nd shot after the boronization (70-95 cm).
E antenna did not fire so only 2 MW dPrad/dt ~ 2.2 (note only 2MW of RF, not to mention the Ohmic power) Wtot ~ 116 kJ H ~ 1.3 Neut rate max - 7e12 Next, on to boronize 50-75 cm with pause at 63 cm. |
| Aug 9 2005 05:26:53:170PM | 1050809014 | Bruce Lipschultz | 1st shot after the boronization (45-70 cm).
No E Antenna Trouble gettting into H-mode even with 2.5 MW out of J port dPrad/dt ~ 5 Wtot not useful because RF only on for 30 ms of H-mode H ~ 1.2 Neut rate max - 2e12 try again and see if we can get 3 MW |
| Aug 9 2005 02:02:24:183PM | 1050809016 | Bruce Lipschultz | 3rd shot after the boronization (50-75 cm).
No E Antenna 3.0 MW out of J port - faulting most of the time. Entered H-mode around 2.0 MW. Pressures in divertor and at midplane seemed closer to normal levels Run scrubbed to fix E port transmitter. We don't have enough power and/or efficiency out of J to make up for the loss of E. |
| Physics Operator Comments | |||
| Aug 9 2005 06:46:28:413AM | Steve Wolfe | Bruce's calibration lamp turned on. | |
| Aug 9 2005 07:03:53:993AM | Steve Wolfe | Load from 1050705018 In seg2, program PG2 to 100V starting at 0.2sec Import Seg1 from 1050525002; leave pg4 at 21ms Load at 9-Aug-2005 07:02:55.00 Open tree /home/wolfe/pcs_scratch -1 Open tree done | |
| Aug 9 2005 08:13:57:633AM | 1050809001 | Steve Wolfe | Shot#1: Data system test Took a little longer than normal in INIT, Got gas ok. Got data. Ratiomatic was off, have to remember to turn it on before first plasma shot. Store complete in 6:18. |
| Aug 9 2005 09:04:31:900AM | 1050809002 | Steve Wolfe | Shot#2: First plasma attempt, no previous boronization. This is the baseline. At RF request, change TF to 144kA (5.2T) Base pressure 3.3e-8 Torr Dud. Needs more gas. Bz is a little negative too. |
| Aug 9 2005 09:32:02:337AM | 1050809003 | Steve Wolfe | Shot#3: Pg4 from 21ms to 28ms 2nd try at baseline shot. Purge B-side lower and fill with He4 for possible ECDC in He after boronizations. I should probably be sure to zero the waveform on PG1, just in case it's accidentally enabled later. Base pressure at INIT=4.6e-8 plasma with multiple H-modes. Lots of runaways. breakdown at 5.3ms, bouncy startup. RF faults out early, J4 retries, J3 doesn't. Second and third H-modes are ohmic. Next shot: turn off pg1 pulse, repeat for better RF |
| Aug 9 2005 09:45:44:727AM | 1050809004 | Steve Wolfe | Shot#4: turn off pg1 pulse, repeat for better RF Base pressure at INIT=8.5e-7 plasma, multiple H-modes, full length Getting baseline offset on BP16_DE of .06V; should have replaced that, but too late now. RF stayed on pretty well, runaways down, but not gone. Still a bounce on startup. Next shot: boronize 15min, 70/83/95 PG4 from 28 to 23ms |
| Aug 9 2005 10:28:34:637AM | 1050809005 | Steve Wolfe | Shot#5:boronize 15min, 70/83/95 Actually, the first ~10minutes was 44/45/103, it turns out you have to enable the change on the PLC screen! PG4 from 28 to 23ms Wait for base pressure down to 2.0e-6, time since boronization off=12 minutes time in recool=42:45 fizzle. So much for just waiting. Breakdown at 12msec, no current rise. Next shot: pg4 back to 28ms |
| Aug 9 2005 10:53:04:903AM | 1050809006 | Steve Wolfe | Shot#6: pg4 back to 28ms Long delay for TS and a gasfill fault. Base pressure at INIT=8.5e-7 fizzle. breakdown is back to 5.7ms, still no current rise, snuffs next shot: repeat |
| Aug 9 2005 11:07:29:730AM | 1050809007 | Steve Wolfe | Shot#7: repeat, still at 28msec Base pressure at INIT=7.5e-7 plasma disruption at .95sec bounce in startup, long hesitation. Got to 145kJ before something killed it. next shot: repeat, hope for no injection |
| Aug 9 2005 11:19:19:730AM | 1050809008 | Steve Wolfe | Shot#8: pg4 from 28 to 26msec plasma, another late breakdown (11ms) but it made it. Bz went negative again. 3 H-modes, Prad around 2MW next shot: boronize for 15minutes, with 70/83/95 ic_ef4 more positive |
| Aug 9 2005 11:50:53:450AM | 1050809009 | Steve Wolfe |
Shot#9: boronize for 15minutes, with 70/83/95
ic_ef4 from -1310 to -1300, pg4 still at 26msec
Don't wait so long this time.
Base pressure at INIT=4e-6
" at count =3.1e-6
fizzle. breakdown at 5.6ms, still no current rise.
next: rcur offset to 1000
|
| Aug 9 2005 12:04:24:903PM | 1050809010 | Steve Wolfe | Shot#10: rcur offset from 1500 to 1000, pg4 still at 26 Base pressure at INIT=1.7e-6 at countdown=1.5e-6 fizzle. Very similar to 9, a little more current. next:rcur back to 1500, pg4 to 24ms |
| Aug 9 2005 12:19:06:887PM | 1050809011 | Steve Wolfe | Shot#11: rcur back to 1500, pg4 form 26 to 24ms Base pressure at INIT=1.2e-6, 1.1e-6 at countdown plasma full length breakdown at 5.0msec Wmhd=164kJ, Prad~1MW+, a couple of early injections next shot: repeat |
| Aug 9 2005 12:35:33:793PM | 1050809012 | Steve Wolfe | Shot#12: repeat Didn't get E-port, 2 H-modes,prad>1.3MW next: boronize 45/56/70 for 15minutes Drop pg4 from 24 to 21msec |
| Aug 9 2005 01:11:26:560PM | 1050809013 | Steve Wolfe | Shot#13: boronize 45/56/70 for 15minutes Drop pg4 from 24 to 21msec Brief power room access in SCBA to reset FMIT#2 It won't reset. We'll try to see how much we can get out of J. Base=2.5e-6 at INIT, 2.1e-6 at countdown. fizzle. breakdown at 5ms, no current rise. next: Pg4 to 19msec |
| Aug 9 2005 01:32:30:717PM | 1050809014 | Steve Wolfe | Shot#14: Pg4 from 21 to 19msec 1.5e-6 at INIT plasma full length, 2.5MW from J alone H-mode is at the end of the RF pulse next: pg4 to 23msec |
| Aug 9 2005 01:51:36:263PM | 1050809015 | Steve Wolfe | Shot#15: pg4 from 19 to 23msec Try for more power from J plasma full length H-mode is earlier, peak Wmhd=122kJ J is faulting early, then recovers. Prad reaches 1.4MW. |
| Aug 9 2005 01:56:26:887PM | 1050809016 | Steve Wolfe | Shot#16: Take another shot while waiting for a decision on stopping the run to fix FMIT#2. plasma full length. J still faulting at this power level. We will shut down the run so the engineers can work on fixing FMIT#2. |
| Engineering Operator Comments | ||||
| Shot | Time | Type | Status | Comment |
| 1 | 08:05:04:900AM | Test | Ok | cycle test |
| 2 | 09:01:08:883AM | Plasma | Ok | |
| 3 | 09:23:42:977AM | Plasma | Ok | |
| 4 | 09:37:36:727AM | Plasma | Ok | |
| 5 | 10:24:08:683AM | Plasma | Ok | |
| 6 | 10:47:25:230AM | Plasma | Ok | |
| 7 | 11:00:32:513AM | Plasma | Ok | |
| 8 | 11:13:11:120AM | Plasma | Ok | |
| 9 | 11:47:45:780AM | Plasma | Ok | |
| 10 | 12:00:49:577PM | Plasma | Ok | |
| 11 | 12:13:23:780PM | Plasma | Ok | |
| 12 | 12:28:48:467PM | Plasma | Ok | |
| 13 | 01:08:15:730PM | Plasma | Ok | |
| 14 | 01:21:07:450PM | Plasma | Ok | |
| 15 | 01:35:11:263PM | Plasma | Ok | |
| 16 | 01:52:16:933PM | Plasma | Ok | |