Miniproposals

Miniproposal: 161 Date Filed: 7/18/1996 Title: JET/C-Mod Dimensionless Identity Experiments First Author: Ian Hutchinson Session Leader: Ian Hutchinson (shots 1-32)

Engineering Operator Run Comment

MP161/Hutch, Goetz,Silva

Session Leader Plans

Physics Operators Plans

Session Leader Summaries

Entered: Jul 7 2004 03:49:17:477PM

Author: To Be Determined

Session Leader 971216 Nominally JET similarity. MP 161. Actually, post-boronization fiducials. SL Hutch PO Goetz. Boronized at higher pressure for 120 psi worth of diborane over the week-end then a day of ECDC in Helium. The morning was a severe trial. A late start because of alternator and several mds sequence problems. Fizzles were frequent all day. In the end we did little more than run a lot of 0.8MA fiducials. However some very encouraging results were obtained from the point of view of plasma clean-up and radiation control. On shot 16 the RF pulled the plasma hard onto the limiter for about 200ms. The next plasma, shot 21, obtained a reasonable H-mode at 1MW RF. ELMs. This shot has a big marfe like emission during the first 300ms, which seems to be a _good_ thing for keeping the plasma clean. The Argon was disabled because it was very obvious that there was a strong rise in X-ray emission following the time of the puff. The next plasma, 23, had a very obvious EDA H-mode at 1MW. Shots 24,26,27 were like it, with the Argon off. Shot 29 was the next with Argon on (lower level). The H-modes are NOT EDA. Shot 31 has Ar off nice EDA. All of the above proves beyond doubt that the Ar levels that we inherited were sufficient to prevent EDA H-modes being obtained. The Ar seems to have been raising the x-ray signals, which are characteristic of core radiation, by about a factor of 2. The Ar plenum pressure was at 5 psi, which is too high.With Ar off, we are getting the EDA characteristics at power levels lower than were typically needed in 1996. On the last two shots before the network fell over and could not get up, RF at 2MW showed clear impurity injections associated with dramatic flashes on the Los Alamos fast camera. This might be a useful way to diagnose any improvements (or otherwise) in RF antenna conditioning and/or performance. Summary _______ Two independent things were good for cleaning up the plasma: 1) Enough of an early gas puff to cause a marfe-like D-alpha episode prior to diversion. 2) Turning off the Argon. Good EDA H-modes were obtained at 1 MW RF, 0.8MA. The RF antennas still need some conditioning.

Physics Operator Summaries

Entered: Jul 7 2004 04:36:58:190PM

Author: To Be Determined

Physics operator summary for 971216 EO: Silva/Bertolino PO: Goetz SL: Hutchinson Run 971216 was in support of MiniProposal 161 - Dimensionless Similarity (JET). The goals for today were to 1) start with fiducials and evaluate operating conditions after the weekend boronization and 2) match the JET equilibrium, ala' that done on 960904035 and then do an RF scan to measure the L->H threshold. The machine was boronized over the weekend at 'high' pressure and a non-outboard sweep. Helium ECDC was done on 971215 and 971215-16. Goal 1 was passed with flying colors. Goal 2 was not attempted. A difficult beginning today. Breakdowns were readily achieved over a wide range of prefill puff lengths and twiddles in Br and Bz. However, current rises and density rises were pratically nonexistent. (One Bz twiddle went too far and resulted in a dud). Prefill puff was scanned up to 24msec in width and ended up at 13msec. The sparker supply was not connected to the sparker until after shot 14. Then, it arced for quite a few shots. It is not at all clear if the sparker makes any difference in getting a current rise. The previous experience of the sparker moving the breakdown time was not evident today. Eventually, somewhat reliable current rises were achieved. Eight of the last twelve attempts produced full length plasma shots today. See the session leader summary for discussion of the EDA H-modes and low radiated powers produced today. The most important thing learned today is that after a heavy boronization, exhibit some patience. It takes a while to get the machine back up and going. Don't wander around in the magnetics wilderness for too long. Engineering, computing, and diagnostics today: Run started late because of the cold weather - the alternator needed some extra time to warm up. A problem with the MDSPlus scope application program that inhibited x-axis evaluation was fixed before the run. The sparker supply was not connected to the sparker - the connection was made between shots 14 and 15. Computer network hang caused the last 45 minutes to be lost. No diagnostic problems today. Scorecard: 32 shots = 11 plasmas + 18 fizzles + 1 dud + 1 eng. duds + 1 test Shot summary for Run 971216: Load 971212036, a fiducial remove voltage from PG3 after 0.4sec coldstart hybrid - all matrices respond Shot change result ____ _____ ______ 1 OH test shot o.k. 2 see above plasma - fiducial - 2 H-modes - early hards 3 PG4=18ms; more PG3 before 0.3; no power to reset shot cycle BR_0=.0072 4 PG4=18ms; more PG3 before 0.3; fizzle - b.d. @ .007 - Br a bit positive BR_0=.0072 5 PG4=17ms; BR_0=.0069 fizzle - b.d. @ .009 - not enough Bz 6 IC_EF4=-1325A fizzle - b.d. @ .007 - not enough Bz 7 IC_EF4=-1300A dud - Bz 2mT positive 8 IC_EF4=-1320A fizzle - fields o.k., must be gas 9 IC_EF4=-1330A; PG4=19msec fizzle - weak - fields o.k. 10 load 971216002 and try again plasma - b.d. @ .005 - fields look the same as 9 11 no changes fizzle - b.d. @ .0065 - Br and Bz too negative because the supply currents are different 12 no changes fizzle - b.d. @ .006 - Bz too negative 13 IC_EF4 = -1325A fizzle - b.d. @ .007 - fields o.k. 14 PG4=24msec fizzle - b.d. @ .006 - fields o.k. 15 PG4=18msec; connect sparker fizzle - b.d. @ .007 - no sparker - a bouncer 16 PG4=16msec plasma - b.d. @ .007 - good current rise 17 RCUR=.669; RF_LOAD_E=0. fizzle - b.d. @ .006 - fields o.k. 18 PG4=19msec fizzle - b.d. @ .006 - fields o.k. 19 RCUR offset = 6700 to slow fizzle - b.d. @ .006 - fields o.k. down Bz; PG4=17msec 20 IC_EF4=-1335A; PG4=16msec fizzle - b.d. @ .006 - almost went 21 PG4=15msec; RCUR offset = plasma - fiducialicious 6500 in segment 1 22 more PG3 after 0.1sec fizzle - b.d. @ .006 23 no changes plasma - nice shot - EDA H-mode 24 RXL=+.004; ZXL=-.011 plasma - nice shot - EDA H-mode 25 RXL=+.006; ZXL=-.015 fizzle - b.d. @ .006 - weak 26 no changes plasma - EDA H-mode 27 no changes plasma - EDA H-mode 28 12msec Ar puff fizzle - b.d. @ .006 - weak 29 no changes plasma - 6 ELMfree H-modes 30 no argon puff fizzle - b.d. @ .006 - weak 31 PG4=14msec plasma - EDA - nice shot - injection 32 PG4=13msec plasma - EDA - nice shot - injection

Session Leader Comments

Physics Operator Comments
Dec 16 1997 08:53:19:200AM		John Goetz	Run 971216 MiniProposal 161 - Dimensionless Similarity (JET) Start with fiducials and evaluate operating conditions Match JET equilibrium, ala' that done on 960904035 and then do an RF scan to measure the L->H threshold. Engineering: Start with setup 971212036 TF under hybrid control K-side with 30PSI deuterium and enable B-top with 5PSI deuterium and enable B-side-lower with 4PSI argon and enable Gate valves: ECE if vacuum status o.k. Coldstart hybrid - all matrices respond
Dec 16 1997 09:39:23:830AM	971216001	John Goetz	Shot 971216001 standard first run of the week OH test shot - o.k. For 971216002 load 971212036 remove voltage from PG3 after 0.4sec
Dec 16 1997 10:08:20:940AM	971216002	John Goetz	Shot 971216002 Plasma; fiducial; 2 H-modes; hard x-rays early too much RF For 971216003 PG4 = 18msec (was 16) increase PG3 before 0.3sec
Dec 16 1997 10:25:04:430AM	971216003	John Goetz	Shot 971216003 no power shot to get the cycle back in order For 971216004 PG4 = 18msec (was 16) increase PG3 before 0.3sec
Dec 16 1997 10:39:38:010AM	971216004	John Goetz	Shot 971216004 Fizzle breakdown @ .007; Br a little positive For 971216005 PG4 = 17msec BR_0 offset = .0069
Dec 16 1997 10:48:00:040AM	971216005	John Goetz	Shot 971216005 Fizzle breakdown @ .009; not enough Bz For 971216006 IC_EF4 = -1325A (was -1340A)
Dec 16 1997 11:11:18:860AM	971216007	John Goetz	Shot 971216007 Dud Bz 2mT too positive For 971216008 IC_EF4 = -1320A (was -1300A)
Dec 16 1997 11:20:17:990AM	971216008	John Goetz	Shot 971216008 Fizzle Bz maybe a bit too positive, but not bad. Must be the gas For 971216009 IC_EF4 = -1330A (was -1320A) PG4 = 19msec (was 17)
Dec 16 1997 11:29:24:680AM	971216009	John Goetz	Shot 971216009 Fizzle - very weak one - breakdown @ .010 Fields are fine - what is going on?! For 971216010 reload 971216002 and watch
Dec 16 1997 11:40:48:740AM	971216010	John Goetz	Shot 971216010 Plasma - breakdown @ .005, right where it needs to be Br is now oscillating around +0, maybe this is the difference RF has gain troubles, need to work them out before this is a fiducial For 971216011 no changes
Dec 16 1997 11:54:17:800AM	971216011	John Goetz	Shot 971216011 Fizzle - breakdown @ .0065 power supply currents have changed between shots 10 and 11 Bz is now too negative and Br too negative For 971216012 no changes
Dec 16 1997 12:03:53:420PM	971216012	John Goetz	Shot 971216012 Fizzle - breakdown @ .006 Br too negative - supply currents are the same as 11, but different than 10 For 971216013 IC_EF4 = -1325A (was -1340A)
Dec 16 1997 12:11:32:020PM	971216013	John Goetz	Shot 971216013 Fizzle - breakdown @ .007 fields look o.k. For 971216014 PG4 = 24msec (was 16msec)
Dec 16 1997 12:33:05:720PM	971216014	John Goetz	Shot 971216014 Fizzle - breakdown @ .006 fields look o.k. cell access to check on sparker - sparker supply not connected to sparker For 971216015 PG4 = 18msec (was 24msec) and hopefully spark away.
Dec 16 1997 12:47:26:120PM	971216015	John Goetz	Shot 971216015 Fizzle - breakdown @ .007 - a bouncer fields look o.k. sparker arced at -1.5sec For 971216016 PG4 = 16msec
Dec 16 1997 01:00:05:600PM	971216016	John Goetz	Shot 971216016 Plasma - breakdown @ .007 - nice current rise still not an acceptable fiducial RF feedback pulled the plasma onto the limiter at 1.0sec For 971216017 RF_LOAD_E=0. RCUR = .669 (was .670)
Dec 16 1997 01:12:37:520PM	971216017	John Goetz	Shot 971216017 Fizzle - breakdown @ .006 - fields look o.k. For 971216018 PG4 = 19msec (was 16)
Dec 16 1997 01:25:16:320PM	971216018	John Goetz	Shot 971216018 Fizzle - breakdown @ .006 - fields look o.k. For 971216019 PG4 = 17msec (was 19) RCUR offset = 6700 (was 7000) to slow down the Bz ramp rate
Dec 16 1997 01:29:37:930PM	971216019	John Goetz	Shot 971216019 Fizzle - breakdown @ .006 - fields look o.k. For 971216020 PG4 = 16msec (was 17) IC_EF4 = -1335A (was -1325A)
Dec 16 1997 01:38:00:950PM	971216020	John Goetz	Shot 971216020 Fizzle - breakdown @ .006 - fields look o.k. - almost a bouncer For 971216021 PG4 = 15msec (was 16) RCUR offset = 6500 in segment 1
Dec 16 1997 01:50:58:840PM	971216021	John Goetz	Shot 971216021 Plasma - breakdown @ .006 - slight hesitation fiducialicious For 971216022 disable argon puff through PG1
Dec 16 1997 02:02:47:810PM	971216022	John Goetz	Shot 971216022 fizzle - b.d. @ .006 - a weak one For 971216023 no changes
Dec 16 1997 02:15:52:820PM	971216023	John Goetz	Shot 971216023 plasma - nice shot - EDA H-mode outer and inner strike points are not in the correct place - too much curvature in the lower divertor region For 971216024 RXL = +.004 (was -.001) ZXL = -.011 @ .65 to -.014 @ 1.1 (was -.006)
Dec 16 1997 02:30:19:250PM	971216024	John Goetz	Shot 971216024 plasma - nice shot - EDA H-mode got the strike points in position, but not until 0.8sec For 971216025 RXL = +.006 @ 0.45sec (was +.004) ZXL = -.015 @ .45 (was -.011)
Dec 16 1997 02:36:16:100PM	971216025	John Goetz	Shot 971216025 fizzle - b.d. @ .006 - fields look o.k. For 971216026 no changes [RXL = +.006 @ 0.45sec (was +.004)] [ZXL = -.015 @ .45 (was -.011)]
Dec 16 1997 02:55:00:330PM	971216026	John Goetz	Shot 971216026 plasma - nice shot - EDA H-mode a good fiducial For 971216027 let RF fiddle D- to E- balance
Dec 16 1997 03:04:47:660PM	971216027	John Goetz	Shot 971216027 plasma - nice shot - EDA H-mode a good fiducial For 971216028 enable B_side_lower and give PG1 a 12msec argon puff
Dec 16 1997 03:21:42:790PM	971216028	John Goetz	Shot 971216028 fizzle - breakdown @ .006 - high Dalpha - weak For 971216029 no changes [enable B_side_lower and give PG1 a 12msec argon puff]
Dec 16 1997 03:33:58:200PM	971216029	John Goetz	Shot 971216029 plasma - 6 ELMfree H-modes For 971216030 disable B_side_lower (no argon)
Dec 16 1997 03:41:16:560PM	971216030	John Goetz	Shot 971216030 fizzle - breakdown @ .006 - weak For 971216031 PG4 = 14msec
Dec 16 1997 03:53:26:810PM	971216031	John Goetz	Shot 971216031 plasma nice EDA - injection kills it - but it is resurrected For 971216032 PG4 = 13msec

Engineering Operator Comments
Shot	Time	Type	Status	Comment
1	09:31:12:620AM	Test	Ok	OH1, OH2 Test OK
2	09:50:19:070AM	Plasma	Ok	no faults/ plasma
3	10:23:10:620AM	Test	Ok	no power state cycle
4	10:30:34:750AM	Plasma	Ok	no faults/ fizzel
5	10:39:57:050AM	Plasma	Ok	no faults/fizzel
6	10:49:31:110AM	Plasma	Ok	no faults fizzel
7	10:59:16:130AM	Plasma	Ok	no faults
8	11:10:56:900AM	Plasma	Ok	no faults fizzel
9	11:21:29:360AM	Plasma	Ok	no faults fizzel
10	11:29:58:460AM	Plasma	Ok	no faults plasma
11	11:42:00:550AM	Plasma	Ok	no faults
12	11:53:39:220AM	Plasma	Ok	no faults fizzel
13	12:05:04:130PM	Plasma	Ok	no faults
14	12:13:33:770PM	Plasma	Ok	no faults
15	12:36:04:880PM	Plasma	Ok	no faults/ shots 1 thru 12 sparker probe was not connected
16	12:49:36:950PM	Plasma	Ok	no faults plasma
17	01:04:20:400PM	Plasma	Ok	no faults
18	01:13:16:290PM	Plasma	Ok	no faults
19	01:24:38:300PM	Plasma	Ok
20	01:32:23:740PM	Plasma	Ok
21	01:40:15:840PM	Plasma	Ok
22	01:53:23:850PM	Plasma	Ok
23	02:03:46:900PM	Plasma	Ok
24	02:16:00:310PM	Plasma	Ok
25	02:30:43:680PM	Plasma	Ok
26	02:42:43:860PM	Plasma	Ok
27	02:54:46:290PM	Plasma	Ok
28	03:15:37:640PM	Plasma	Ok
29	03:26:12:700PM	Plasma	Ok
30	03:37:34:650PM	Plasma	Ok
31	03:46:08:680PM	Plasma	Ok
32	03:59:40:670PM	Plasma	Ok