| Miniproposals | ||||||||||
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| Operators | |
| Session leader(s): | Stewart Zweben,Robert Granetz |
| Physics operator(s): | Steve Wolfe |
| Engineering operator(s): | Bill Cochran,Ed Fitzgerald,Gary Dekow |
| Engineering Operator Run Comment |
| MP#429 SOL Turbulence in limiter H-modes MP#424 Gas Jet disruption mitig |
| Session Leader Plans |
| Entered: Aug 24 2005 12:31:10:517PM |
| Author: Robert Granetz |
MP #424 -- Gas jet disruption mitigation at higher plasma thermal energy
and pressure.
Session leaders: R. Granetz
Physics operator: S. Wolfe
Overnight ECDC in D2; Bake at 60 C.
Run begins at 09:00 and ends at 17:00.
*************
NOTE: we will take over the run from S. Zweben's MP sometime during the
day, and hopefully get a half-day for this gas jet MP.
*************
Power systems as on 1050811008 (1.0 MA, 5.2 T, SNL fiducial), except
set Btor at 5.4 T rather than 5.2 T since J-port is now back to 78 MHz.
A-coil configuration: normal [+Dtop -Dbot -Jtop +Jbot] and enabled.
Gas Setup:
fill B-Top with 6 psi D2 Hybrid enabled (PG4)
fill B-side lower with 1 psi Ar + 2 psi Ne Hybrid DISABLED (PG1)
leave B-side upper with whatever Hybrid DISABLED (PG2)
fill B-main (C-side) with 40 psi D2 Hybrid enabled (PG3)
No NINJA for this run.
*************
GAS JET SHOULD HAVE HIGH-PRESSURE (70 BAR) KRYPTON BOTTLE INSTALLED.
*************
Between-shot boronization should be ready to go, although we will not use
it for the start of the run.
Torvac setup: unnecessary diagnostic gate valves (ECE, VUV) should be kept
closed on all gas jet shots.
Enable the following, assuming no vacuum problems:
Z-bolo shutters
Necessary diagnostics:
IR camera
Fast PSI camera on B-horizontal, starting at t=0.800 s and
appropriate filter.
Thomson scattering, with adjustable timing between the two lasers
Bolometry
AXUV array with reduced gain
Halo current Rogowskis
SX arrays with fast sampling window (t=0.795 to 0.820 s)
Mirnov Bp fluctuations
-------------------------------------------------------------------------------
ICRF Setup: All available transmitters in run on at 08:30. We'll want
2.5+ MW at the start of the MP, and possibly 3+ MW later in
the run.
-------------------------------------------------------------------------------
Run plan: Start with krypton at 70 bar, 2 ms. The goal is to get the same
extensive set of measurements, including IR images, as during the
previous gas jet runs, but with krypton. If the ICRF heating is
good, try several shots with 3+ MW of RF power to get 180+ kJ.
|
| Entered: Aug 24 2005 04:28:42:073PM |
| Author: Stewart Zweben |
| Run to measure edge turbulence in SOL of near-circular limited Ohmic plasma
MP #429 1) shots 1-3: establish baseline: I=0.8 MA, B=5.4 MA outer gap = 3 cm inner wall limited near-circular shape kappa=1.0-1.2 check GPI images for quality of signal 2) shots 4-8: optimize outer gap scan outer gap from 2 -4 cm to find optimal image 3) shots 8-11: increase density increase density as much as possible without MARFES or disruption 4) shots 12-15: repeat for good statistics repeat optimal shot 4 times end |
| Physics Operators Plans |
| Entered: Aug 24 2005 05:06:05:433PM |
| Author: Steve Wolfe |
Physop Plan for Thursday 1050825 ----------------------------------- Overnight ECDC in D2, bake at 60C Run starts at 09:00 and ends at 17:00. We may need between-shot boronization, so the diborane bottle should be switched (20% bottle removed, old 6 liter 10% diborane bottle put in its place) in the morning. This should be done as early as possible, and will require locking out access. The bottle should NOT be opened until requested during the run. *** NOTE: Set up for between-shot boronization*** but do not open the diborane bottle for the beginning of the run. Between-shot boronization may be used for the second half of the run. The High-Pressure (70 bar) Krypton bottle must be installed on the gas jet system before the run. The High-Pressure Neon bottle should be available for possible use later in the day. This run is supposed to be divided between two MiniProposals, MP#429 SOL Turbulence in limiter H-modes SL:S. Zweben MP#424 Gas Jet disruption mitigation SL:R. Granetz We will start with MP#429, but may switch early if the results are not promising. Otherwise we will switch experiments around 1:00PM. Engineering setup for MP#429: Power systems as on 1050615025 except OH2U and OH2L current limits should be [-30,30] instead of [-26,30]. Acoil settings should be standard (+Dtop -Dbot -Jtop +Jbot) start time= 0.3sec, stop time=2.0sec, hybrid enabled. Gas Setup: fill B-Top with 6 psi D2 Hybrid enabled (PG4) fill B-side lower with 1 psi Ar plus 2 psi neon Hybrid DISABLED (PG1) leave B-side upper as is He3 Hybrid DISABLED (PG2) fill B-main (C-side) with 40 psi D2 Hybrid enabled (PG3) NINJA setup=15psi D2 Enable the following gate valves and shutters, assuming no vacuum problems: ECE, VUV, Z-bolo shutters (NOTE: the VUV shutter will be closed for the second half of the run). ICRF setup: Ready for RUN-ON by 8:30, but not set to RUN-ON until the second experiment. Physop setup: -------------- MP#429 calls for limited plasmas with kappa~1.0. Start with programming from 1050615025, which had kappa=1.2 Set CLEARIN=-0.06, flatten RCUR=.656, ZXL=-.02,ZXU=+.02 Consider changing RXL=RXU=0.00 Consider IC_EF4U from 2000->1000 to keep EF2's from railing reduce NL04 to 7e19 Setup Acoil feedback. Change TF to 5.4T (-150000) 1)Tweak to get good round plasma SL to evaluate signal and decide whether to proceed 2) Scan outer gap per SL plan 3) Scan density per SL 4) Repeat best condition MP#424 setup: ------------ Gas Jet should have high-pressure (70Bar) Krypton bottle installed before run. Between-shot boronization MAY be used later in this part of the run. Torvac setup: unnecessary diagnostic gate valves (ECE, VUV) should be kept closed on all gas jet shots. Enable the following, assuming no vacuum problems: Z-bolo shutters Power systems as on 1050811008 Start with PCS from 1050811008, except change TF to 5.4T RF should be on at 2.5MW to start, may want more later in run if available. |
| Session Leader Summaries |
| Entered: Aug 25 2005 04:08:08:020PM |
| Author: Stewart Zweben |
| shot 1: Ninja not armed, so no GPI puff
outer gap about 0.5 cm PSI-5 triggered at 0.85 sec, dark - use for background levels shot 2: Ninja puff OK @ 30 psi, see JT diode signals OK outer gap about 1.5 cm PSI-5 triggered at 0.85 sec, data OK but lost due to full disk shot 3: early disruption at 0.2 sec shot 4: Ninja puff OK @ 30 psi, diodes OK outer gap about 2.5 cm PSI-5 triggered at 0.9 sec, image data OK, transferred to tree shot 5: Ninja puff OK at 45 psi; diodes OK outer gap about 2.5 cm PSI-5 triggered at 0.85 sec, image data OK, transferred to tree shot 6: fizzle shot 7: Ninja puff OK at 45 psi; diodes OK outer gap about 2.5 cm PSI-5 triggered at 0.85 sec, image data OK but lost due to full disk shot 8: fizzle shot 9: Ninja puff OK at 45 psi; diodes OK outer gap about 3.2 cm PSI-5 triggered at 0.85 sec, image data OK, did not transfer to tree but maybe saved on PSI-5 PC shot 10: Ninja puff OK at 45 psi; diodes OK outer gap about 3.3 cm PSI-5 triggered at 0.85 sec, image data OK, transferred to tree shot 11: fizzle shot 12: Ninja puff OK at 45 psi; diodes OK outer gap about 3.5 cm PSI-5 triggered at 0.85 sec, image data OK, not transferred to tree but saved on PSI-5 PC shot 13: Ninja puff OK at 45 psi; diodes OK outer gap about 3.6 cm PSI-5 triggered at 0.83 sec, image data OK, not transferred to tree but saved on PSI-5 PC shot 14: short plasma, no data shot 15: short plasma, no data |
| Entered: Aug 25 2005 05:26:34:990PM |
| Author: Robert Granetz |
| Session leader summary for Thursday 25 Aug 2005: MP #424: Gas jet disruption mitigation Session leader: R. Granetz, D. Whyte Physics operator: S. Wolfe Today's 1/2-day run concentrated on krypton gas jets. We were successful at getting a good set of Thomson profiles, IR images, fast images of the gas jet, etcetera. Basic findings are that the radiated energy fraction was marginally higher than with argon (krypton points were comparable to the highest values of the argon points), and halo currents were comparable to the argon values. So it's clear that higher Z is beneficial for these effects, but only marginally at this point. It's doubtful that going higher in Z would give further improvement. Also, the edge density did not rise with krypton, unlike the observations with all the other lower Z gas jet experiments. After we finished with krypton, we decided to switch back to neon. This took an hour to changeover and set up, and then we ran into some problems with plasmas disrupting very early. The last shot (027) was the only neon gas jet shot that worked as planned. |
| Physics Operator Summaries |
| Entered: Aug 25 2005 05:46:27:690PM |
| Author: Steve Wolfe |
Physop summary for Thursday, Aug 25, 2005
Shots 1-15: MP#429 SOL turbulence in circular limiter plasmas SL: Zweben
Shots 15-27: MP#424 gas jet disruption mitigation
SL:Granetz/Whyte
PO: wolfe
We were moderately successful in getting low elongation limiter
plasmas, kappa~1.2, mainly using large negative CLEARIN programming.
I only moved the ZX's out to +/-.03, and it wasn't clear that this
was helpful. Since the CLEARIN observer is really looking at the
flux difference between Z=-.39,R=.56 and Z=0,R=.45, moving the xpoint
location can have unexpected interactions with this control. At any
rate, the SL was satisfied with kappa=1.2. It is probably not possible to
do much better without moving the x-points much farther away, preferably
out of the vessel altogether.
It turns out that the apparent limit on the OH2U noted in the 1050615
run was still present even with the PLC current limit set to -30 and
even -35kA. The problem seems to be a voltage limit (margin angle?)
rather than running into the current rail. This seems to be slightly
different between the oh2u and oh2l supplies. The result is that we
still lost outer gap control late in the pulse, and I ended up shortening
the shot to avoid the high flux swing, since the experiment was essentially
over after 1sec. Shots 6-15 have EOF at 1.2sec. Bill will look into the
power supply behavior when we have a chance.
The outer gap scan was accomplished ok, with maximum gap around 3.5cm
ending up being the one that gave the best view for the camera. The density
scan was not attempted.
The video system had difficulties with its PC, including a full disk and
a problem with ftp'ing results to MdsPlus. These cost some shots and
required one long cell access. There was also some problem with the images
displayed on video_display from the tree not looking as good as the images
on the PC. For the last several shots the data were kept on the PC and
will be transferred to the trees later by hand.
The morning run was plagued by injections and disruptions. There were a number of early injections around .11 - .13 sec, some of which were terminal and
others took a bite out of the current but the shots recovered.
Shots 10, 12, and 13 disrupted just after the fast camera time,
and 14 and 15 disrupted earlier. These seemed to have injections, but
10,12, and 13 may have been made more vulnerable by the fact that they were at q95~3.0. Shots 6, 8, and 11 fizzled.
The gas jet run started out well on shot 16, especially considering that
#15 had been a .13sec disruption. Shots 16-23 were all successful gas jet
disruptions using krypton. No adjustments to the startup or anything else
were required during this sequence. After #23 there was an hour long cell
access to change over to neon injection. Following this delay, the bad
behavior of the morning seemed to come back: On shot#24 the gas jet failed
to fire, but the plasma had an early injection that almost killed it,
followed by a marfe, and ended up disrupting at 1.39sec. Shot 25 had a
terminating injection around .13sec, and shot 26 developed an early marfe
that stopped the current rise and then was apparently killed by an
injection. For the last shot (#27) the density rise was decreased and
programmed current increased to try to ameliorate the marfe, and we got
a final successful gas jet termination with neon.
Scorecard:
-----------
Tests 0
Duds 0
Fizzles 3
Plasmas 24 (5 short disruptions, 19 "useful")
------- --
Shots 27
|
| Session Leader Comments | |||
| Aug 25 2005 01:11:33:710PM | 1050825016 | Robert Granetz | Fill plenum with 57 bar (max supply pressure) of krypton. Turn on fast valve trigger (J221:OTUPUT_12). Enable torus gate valve (GV1). There's an overheating problem with the Hovac pump that we'll have to monitor, because the PLC won't allow system to fire if the "ready" bit is off. |
| Aug 25 2005 01:29:08:443PM | 1050825016 | Robert Granetz | Shot -- Good shot. Krypton gas jet fired. I_halo=117 kA. Current quench starts at t=0.808 s. Current quench duration is about 1 ms. Prf=2.5 MW. Wth=115 kJ Plenum gas: krypton Pulse length (ms): 2.0 Plenum pre -pulse pressure (bar): 57 Plenum post-pulse pressure (bar): 54 Plenum change in pressure (bar): 4 Martin reports that the FRCECE can see the temperature collapse. Next shot: move gas pulse trigger by 2 ms (to 0.802 ms). Increase pulse width to 3 ms (from 2 ms) |
| Aug 25 2005 01:41:48:863PM | 1050825017 | Robert Granetz | Shot -- Good shot. Krypton gas jet fired. I_halo=108 kA. Current quench starts at t=0.810 s. Current quench duration is about 1 ms. Prf=2.3 MW, with faults. Wth=94 kJ. Plenum gas: krypton Pulse length (ms): 3.0 Plenum pre -pulse pressure (bar): 57 Plenum post-pulse pressure (bar): 54 Plenum change in pressure (bar): 3 |
| Aug 25 2005 01:44:38:507PM | 1050825017 | Robert Granetz | Note: no fizzle, so it doesn't seem at first glance that krypton is contaminating things. |
| Aug 25 2005 01:57:44:507PM | 1050825017 | Robert Granetz | IR camera shows very little thermal deposition at the disruption. This would be consistent with krypton being a strong radiator of the plasma energy. |
| Aug 25 2005 01:59:45:460PM | 1050825017 | Dennis Whyte | The SX0 array shows a large increase in SXR emission
after the Krypton injection. This is almost certainly caused by excitation of L-shell radiation from the krypton, which lies in the energy range 1.8 - 2.7 keV, which can be detected by the SXR arrays. This makes the SXR arrays a valuable diagnostic tool for both measuring the presence of Kr atoms/ions and Te> ~ 1 keV. |
| Aug 25 2005 02:07:44:460PM | 1050825017 | Robert Granetz | Jim Terry got fast imaging data of the gas jet (no filter, looking at total light). |
| Aug 25 2005 02:01:29:973PM | 1050825018 | Robert Granetz | Shot -- Good shot. Krypton gas jet fired. I_halo=130 kA. Current quench starts at t=0.813 s. Current quench duration is about 1-1.5 ms. Prf=2.4 MW Wth=103 kJ. Plenum gas: krypton Pulse length (ms): 3.0 Plenum pre -pulse pressure (bar): 57 Plenum post-pulse pressure (bar): 54 Plenum change in pressure (bar): 3 |
| Aug 25 2005 02:18:39:817PM | 1050825019 | Robert Granetz | Shot -- Good shot. Krypton gas jet fired. I_halo=134 kA. Current quench starts at t=0.813 s. Current quench duration is about 1.5 ms. Prf=2.7 MW Wth=104 kJ. Plenum gas: krypton Pulse length (ms): 3.0 Plenum pre -pulse pressure (bar): 57 Plenum post-pulse pressure (bar): 54 Plenum change in pressure (bar): 3 |
| Aug 25 2005 02:23:37:960PM | 1050825020 | Robert Granetz | Shot -- Good shot. Krypton gas jet fired. I_halo=119 kA. Current quench starts at t=0.813 s. Current quench duration is about 1 ms. Prf=2.7 MW Wth=100 kJ. Plenum gas: krypton Pulse length (ms): 3.0 Plenum pre -pulse pressure (bar): 57 Plenum post-pulse pressure (bar): 54 Plenum change in pressure (bar): 3 |
| Aug 25 2005 02:49:41:523PM | 1050825020 | Dennis Whyte | The temporal evolution of the pressure in the
upstream tube shows that about 2/3 of the gas injection is being injected into a vacuum vessel with no plasma! This is one of the issues with Krypton gas flow being so slow due to its high atomic number/mass. |
| Aug 25 2005 02:40:27:723PM | 1050825021 | Robert Granetz | Shot -- Good shot. Krypton gas jet fired. I_halo=96 kA. Current quench starts at t=0.813 s. Current quench duration is about 1 ms. Prf=2.5 MW Wth=104 kJ. Plenum gas: krypton Pulse length (ms): 3.0 Plenum pre -pulse pressure (bar): 58 Plenum post-pulse pressure (bar): 55 Plenum change in pressure (bar): 3 We need a couple more shots like this to complete the Thomson scan. |
| Aug 25 2005 02:54:47:083PM | 1050825022 | Robert Granetz | Shot -- Good shot. Krypton gas jet fired. I_halo=104 kA. Current quench starts at t=0.813 s. Current quench duration is about 1.5 ms. Prf=2.4 MW Wth=104 kJ. Plenum gas: krypton Pulse length (ms): 3.0 Plenum pre -pulse pressure (bar): 57 Plenum post-pulse pressure (bar): 54 Plenum change in pressure (bar): 3 |
| Aug 25 2005 03:07:03:660PM | 1050825023 | Robert Granetz | Shot -- Good shot. Krypton gas jet fired. I_halo=125 kA. Current quench starts at t=0.813 s. Current quench duration is about 1.5 ms. Prf=2.4 MW, faulting Wth=100 kJ. Plenum gas: krypton Pulse length (ms): 3.0 Plenum pre -pulse pressure (bar): 57 Plenum post-pulse pressure (bar): 54 Plenum change in pressure (bar): 3 |
| Aug 25 2005 03:07:38:520PM | 1050825023 | Robert Granetz | Done with krypton. We're going to have a long cell access now to switch over to neon. |
| Aug 25 2005 03:10:55:193PM | 1050825023 | Dennis Whyte | The TS and interferometry agree that at the
time of TQ (TS pulse) .8128 s, that the core density has not increased....yet we are clealry seeing the Te collapse to ~300 eV. Yet the soft x-ray array sees Kr L-shell radiation emanating from the core. This suggests that very small amounts of Kr have provided enough radiation losses to quench the plasma, but without significant increase in free electron density through krypton ionization. We will have to check if this is consistent with a 0-D flux surface radiation calculations in KPRAD. |
| Aug 25 2005 04:19:54:007PM | 1050825024 | Robert Granetz | Shot -- Gas jet didn't fire, but the plasma disrupted at 1.4 s. We don't know what caused the disruption, but it might be a good unmitigated comparison shot. I think the pump "ready" status went off, which prevents the PLC from firing the system. I've turned off the pump to let it cool and to try resetting it. |
| Aug 25 2005 04:37:14:693PM | 1050825025 | Robert Granetz | Shot -- Plasma, but disrupted very early. Neon gas jet fired anyway, well after the plasma ended. Plenum gas: neon Pulse length (ms): 2.0 Plenum pre -pulse pressure (bar): 70 Plenum post-pulse pressure (bar): 62 Plenum change in pressure (bar): 8 |
| Aug 25 2005 04:47:09:053PM | 1050825026 | Robert Granetz | Shot -- Plasma, but another early disruption. Neon gas jet fired anyway, well after the plasma ended. Plenum gas: neon Pulse length (ms): 2.0 Plenum pre -pulse pressure (bar): 70 Plenum post-pulse pressure (bar): 62 Plenum change in pressure (bar): 8 Next shot will be the last one for the day. |
| Aug 25 2005 04:57:01:270PM | 1050825027 | Robert Granetz | Shot -- Good shot. Neon gas jet fired. I_halo=134 kA. Current quench starts at t=0.813 s. Current quench duration is about 1.5-2 ms. Prf=2.5 MW Wth=112 kJ. Plenum gas: neon Pulse length (ms): 2.0 Plenum pre -pulse pressure (bar): 70 Plenum post-pulse pressure (bar): 63 Plenum change in pressure (bar): 7 End of run. |
| Physics Operator Comments | |||
| Aug 25 2005 07:31:41:343AM | Steve Wolfe | Setting up for the morning experiment - MP#429 circular limiter plasmas
Load from 1050615025 (all segs) CLEARIN to -.06, including changing the early point from (.15,-.03) to (.09,-.06); note that the initial error in a normal shot is negative. Also move the 2sec point to -.06 RCUR to .656 from .37sec to 1.5sec ZXL to -.02 from the start of seg2 to the end (this also normally starts with negative error ZXU to +.02 (some of these points were at .03, may go back but want to keep it symmetric) NL04 from 1e20 to 7e19 IC_ef4u from 2000->1000 RXL to +.014, and copy RXL->RXU I probably ought to symmetrize all the gains too, but that seems a bit overboard. Set up acoil feedback per my instructions: 1) Load Wire from wire 9,seg2, 1050722024 onto wire 9 2) Set Integrator Gate C to start at 0.3sec 3) Zero ACOIL_CUR on ALL_V's screen Check on seg1: PG4 at 25msec IC_EF4U at -1295 BR0 from -.0001 to 0.0 Load/Clean and do a PCS_compare; it finds the ef4 and PG4 (old value was 21ms), along with a bunch of points on pg3. Leave it alone. Load at 25-Aug-2005 07:24:27.00 Open tree /home/wolfe/pcs_scratch -1 Open tree done | |
| Aug 25 2005 09:08:37:023AM | 1050825001 | Steve Wolfe | Shot#1: Trying for round plasma, per MP#429 Note: pg4 puff is 26msec, not 25 as claimed in setup plasma full length eout=1.2, nl04=9.1e9 (higher than programmed) outer gap is 0.5 going to 0.0? Seg1 pg3 puff is too early Startup looks ok, maybe a little fast. Three injections in flattop next shot: rcur in, zx's out, clearin to -.065 reduce seg1 and seg2 pg3 |
| Aug 25 2005 09:31:13:787AM | 1050825002 | Steve Wolfe | Shot#2: rcur in to .650, zx's out to +/-.03, clearin to -.065 reduce seg1 and seg2 pg3 plasma, marfe's and disrupts at 1.75sec Big density rise from NINJA at 0.8sec Eout still 1.2, outer gap is 1.5cm, dropping at the end of the shot. OH2U seems to be railing again. Next shot: increase outer gap by 1cm Raise OH2 current limits from -30 to -34kA |
| Aug 25 2005 09:52:12:833AM | 1050825003 | Steve Wolfe | Shot#3: rcur in to .645, Raise OH2 current limits from -30 to -34kA Shot#2 had a late bd, no change made early disruption? Disrupts at .11sec Lots of runaways, startup looks a little funny Could be an injection at .04sec that does it in? Current at 0.1 is only 360kA, vertical position way off, chopper goes berserk. I think this is just a bad startup. Try again |
| Aug 25 2005 10:06:06:880AM | 1050825004 | Steve Wolfe | Shot#4: Try again with rcur in to .645, Raise OH2 current limits from -30 to -34kA plasma to 1.75sec, big bite out of the current around .12sec, looks like an injection. outer gap is now 2.5 cm. OH2U still railing around 1.3sec. Startup looks ok, no changes NINJA pressure will be increased for next shot. |
| Aug 25 2005 10:14:19:630AM | 1050825005 | Steve Wolfe | Shot#5: Increase ip program at .1sec(450->550) and .2sec(700->750) to better match real current rise. NINJA pressure will be increased plasma to 1.8sec, pulled the PF breaker after the disruption. Startup bouncy, with runaways. Next shot: raise pg4 |
| Aug 25 2005 10:34:42:820AM | 1050825006 | Steve Wolfe | Shot#6: raise pg4 to 30msec I think the oh2u problem is that it is just voltage limited. There seems to be a slight asymmetry in the upper and lower supplies. Start current rampdown at 1.2sec and reduce oh2 current limits to -30kA again. fizzle. Bounced again, didn't raise it enough. Next shot: turn on Ar/Ne puff (pg1 40msec), pg4 to 33msec |
| Aug 25 2005 10:52:48:740AM | 1050825007 | Steve Wolfe | Shot#7: turn on Ar/Ne puff (pg1 40msec), pg4 to 33msec plasma to 1.8sec, injection takes a bite at ~.12 sec startup better, no bounce no runaways. Current rise is still fast 580kA at .1sec That injection is suspiciously close to crowbar Next shot: increase outer gap by another 1cm |
| Aug 25 2005 11:04:27:553AM | 1050825008 | Steve Wolfe | Shot#8: RCUR from .645->.640 I had forgotten to ask for B-side lower enable previously Do it now. fizzle. Very late breakdown 13msec! Bz too positive. next shot: ef4 to -1310 |
| Aug 25 2005 11:22:39:083AM | 1050825009 | Steve Wolfe | Shot#9: RCUR=.640 ef4 to -1310 plasma to 1.65sec, outer gap=3.3cm, kappa=1.3 Startup looks good, no runaways no bounce Camera didn't get data, disk full again. try for smaller elongation. |
| Aug 25 2005 11:59:28:677AM | 1050825010 | Steve Wolfe | Shot#10: try for smaller elongation. CLEARIN from -.065 to -.075, no startup changes. 30minute delay to reboot PC in the cell. plasma to .9sec, not sure what killed it. Might have been Brian's probe, but he doesn't see any arcing. late breakdown again, 9msec Could stand a little lower bz still, I guess. |
| Aug 25 2005 12:08:03:350PM | 1050825011 | Steve Wolfe | Shot#11: EF4 to -1325 otherwise repeat. Fizzle. Breakdown time ok, turns inside Drop the fill 2ms |
| Aug 25 2005 12:25:10:130PM | 1050825012 | Steve Wolfe | Shot#12: EF4 at -1325 Drop the fill 33->31ms plasma to .85sec again, so it isn't Brian. q95 is very close to 3.0. We're getting injections at .73 and a big one at .848. next shot: drop pg4 another 2ms |
| Aug 25 2005 12:40:51:083PM | 1050825013 | Steve Wolfe | Shot#13: drop pg4 to 29ms plasma to .87sec again. It's reproducible. This one bounced on startup, so don't drop the pre-puff next time. raise nl4 demand to .9 |
| Aug 25 2005 12:48:05:477PM | 1050825014 | Steve Wolfe | Shot#14:raise nl4 demand to .9 plasma, shorter, .4sec next:nl4 demand to .7, pg4 down to 27ms |
| Aug 25 2005 01:24:45:363PM | 1050825014 | Steve Wolfe | On shot#14 there is a one chop spike on bmain, bside lower and bside upper at 0.010sec. Note that bside upper is not even enabled and there is no corresponding output from dpcs to any of these valves. Seems to be a noise spike, doesn't have any effect that I can see, but I've never seen this behavior before. |
| Aug 25 2005 01:05:47:117PM | 1050825015 | Steve Wolfe | Shot#15:nl4 demand back to .7, pg4 down to 27ms plasma very short. disrupts at .13sec. I don't know what we've done, but the machine is not happy. Changing over to Bob's gas jet run. |
| Aug 25 2005 01:23:34:693PM | 1050825016 | Steve Wolfe | Shot#16: import seg2 from 1040811008 and change tf to -150000 touch wires 2 and 4 to clear the timestamp problem No startup changes. No reason to think we won't have another disruption before Bob's puff. plasma to .805sec, that was Bob. RF ran Prf~2.3MW, Wmhd~120kJ, Rneut~1e13 at the disruption Next shot: PCS repeat |
| Aug 25 2005 01:40:34:787PM | 1050825017 | Steve Wolfe | Shot#17: repeat, Bob delayed puff by 2ms plasma to .810 Lower neuts. RF faulted and dropped out of H-mode before the puff. Startup ok, although there is a large CIII signal. next shot: repeat |
| Aug 25 2005 01:58:36:630PM | 1050825018 | Steve Wolfe | Shot#18: repeat. Bob moves jet puff another 3ms later INIT at 18 minutes, p0=1.4e-6 plasma to .813sec, 103kJ at the disruption Startup still ok, CIII signal still elevated. next: repeat |
| Aug 25 2005 02:12:42:210PM | 1050825019 | Steve Wolfe | Shot#19: repeat, maybe more RF plasma to .813 again. Neuts peak at 1e13, but fall before the killer. Startup not as good, spike at 18ms on Zmeter Next:No changes |
| Aug 25 2005 02:24:45:850PM | 1050825020 | Steve Wolfe | Shot#20: repeat, maybe more RF Sameo same-O. Peak wmhd=116, but down to 100 before the jet. Another spike on the zmeter at 15ms, but it keeps going next shot: repeat |
| Aug 25 2005 02:36:56:117PM | 1050825021 | Steve Wolfe | Shot#21: repeat Disrupted on schedule; I thought it looked shorter on the TV but it's right on the line. Startup still hanging in there. Stewart would have done better if he let Bob disrupt his shots. |
| Aug 25 2005 02:49:18:413PM | 1050825022 | Steve Wolfe | Shot#22: repeat Boring! Neuts~9e12, wmhd~105kJ Startup still looks good. One or two more like this, then they'll change something |
| Aug 25 2005 03:04:57:210PM | 1050825023 | Steve Wolfe | Shot#23: repeat Looks the same to me. TS is considering whether they need more data from the time series. This will be the last Kr shot; next change to Neon There will be a cell access |
| Aug 25 2005 04:24:30:663PM | 1050825024 | Steve Wolfe | Shot#24: Same plasma, neon in the gas jet. After about 70 minutes for the bottle changeover. Gas jet failed, plasma to 1.4sec There was a big marfe in current rise. Also some runaways. Bite out of the current at .1sec or so. Looks like a detachment late in flattop, prior to the disruption next shot: drop pg4 by 2ms |
| Aug 25 2005 04:32:52:570PM | 1050825025 | Steve Wolfe | Shot#25: drop pg4 by 2ms to 25ms short disruption. Something hits at .11, this time it doesn't survive. This looked sort of like #15. Early current rise was very fast, but no runaways. next shot: just repeat and cross your fingers |
| Aug 25 2005 04:46:10:927PM | 1050825026 | Steve Wolfe | just repeat and cross our fingers Another short one. This one bounced,got some runaways. Injection comes around .25sec next shot: increase pg4 2ms and slow down nl04 |
| Aug 25 2005 05:00:10:977PM | 1050825027 | Steve Wolfe | Shot 27:increase pg4 2ms to 27ms and slow down nl04 rise before .5sec also increase the .2sec ip point from 700 to 750ka plasma to the jet time. neuts at 1e13, wmhd=112kJ That's it for the day. |
| Engineering Operator Comments | ||||
| Shot | Time | Type | Status | Comment |
| 1 | 09:01:26:710AM | Plasma | Ok | |
| 2 | 09:17:53:770AM | Plasma | Ok | |
| 3 | 09:41:56:007AM | Plasma | Ok | |
| 4 | 09:57:10:147AM | Plasma | Ok | |
| 5 | 10:10:37:460AM | Plasma | Bad | OH2 type 1 fault |
| 6 | 10:32:29:710AM | Plasma | Ok | |
| 7 | 10:45:58:037AM | Plasma | Ok | |
| 8 | 11:01:10:867AM | Plasma | Ok | |
| 9 | 11:15:20:317AM | Plasma | Ok | |
| 10 | 11:52:12:960AM | Plasma | Ok | |
| 11 | 12:05:26:613PM | Plasma | Ok | |
| 12 | 12:18:33:990PM | Plasma | Ok | |
| 13 | 12:31:01:273PM | Plasma | Ok | |
| 14 | 12:43:32:240PM | Plasma | Ok | |
| 15 | 12:59:53:473PM | Plasma | Ok | |
| 16 | 01:18:34:723PM | Plasma | Ok | |
| 17 | 01:33:54:007PM | Plasma | Ok | |
| 18 | 01:54:47:130PM | Plasma | Ok | |
| 19 | 02:07:14:380PM | Plasma | Ok | |
| 20 | 02:19:37:210PM | Plasma | Ok | |
| 21 | 02:32:55:773PM | Plasma | Ok | |
| 22 | 02:45:59:537PM | Plasma | Ok | |
| 23 | 02:58:32:833PM | Plasma | Ok | |
| 24 | 04:13:42:973PM | Plasma | Ok | |
| 25 | 04:26:57:410PM | Plasma | Ok | |
| 26 | 04:39:19:740PM | Plasma | Ok | |
| 27 | 04:51:48:410PM | Plasma | Ok | |