| Miniproposals | ||||||||||
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| Operators | |
| Session leader(s): | Bruce Lipschultz |
| Physics operator(s): | Earl Marmar |
| Engineering operator(s): | Andy Pfeiffer,Gary Dekow,Bill Parkin |
| Engineering Operator Run Comment |
| MP417: Post-boronization evaluation (first half) MP397: Comparison of C- |
| Session Leader Plans |
| Entered: Jun 21 2005 05:03:30:997PM |
| Author: Bruce Lipschultz |
| MP417- 'Plasma performance, boronization and ICRF heating effectiveness with high-Z antenna guards and all-metal walls'
1050622 The purpose of this part of today's run is to evaluate the change in boronization. There should have been a shorter period boronization (60PSI DiBorane) last night, with reduced sweep - 78-103 cm, dwell at 78.5 cm. The intent is to only boronize the antennas and outer limiters and see if that is effective in reducing Mo sources for the usual amount of time. To evaluate the boronization we will bring up the rf power to ~ 3 MW and see how fast the confinement comes up, if at all. Past experience means this is about 10 shots - perhaps to half-day. Then, the run would be passed over to the JFT-2M comparison. |
| Physics Operators Plans |
| Entered: Jun 21 2005 04:59:59:043PM |
| Author: Earl Marmar |
| MP417: Post-boronization evaluation (first half)
MP397: Comparison of C-Mod EDA with JFT2M HRS (second half) Session leaders: B. Lipschultz/Y. Lin (first half) A. Hubbard (second half) Physics operator: E. Marmar Prior to the run, plan overnight boronization with the following parameters: . dP of 60 psi . scan ECDC resonance from 78 cm to 103 cm with dwell at 78.5 cm follow with normal post-boronization ECDC regimen Run begins at 09:00 and ends at 17:00. Power systems as on 1050610001 (1.0 MA, 5.4 T, SNL fiducial) 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 Hybrid DISABLED (PG1) leave B-side upper with whatever Hybrid disabled fill B-main (C-side) with 30 psi D2 Hybrid enabled (PG3) NINJA not used today Enable the following gate valves and shutters, assuming no vacuum problems: ECE, VUV, Z-bolo shutters ------------------------------------------------------------------------------- ICRF Setup: All transmitters in run on at 08:30. |
| Session Leader Summaries |
| Entered: Jun 22 2005 05:51:40:667PM |
| Author: Bruce Lipschultz |
| MP417- 'Plasma performance, boronization and ICRF heating effectiveness with high-Z antenna guards and all-metal walls'
1050622 Mixed results from today's run. The RF did condition up pretty quickly, although steady RF pulses were not achieved too often till later in the run (shots 14-15 for example). The stored energy did achieve reasonable values, similar to 1050610020: 160-170 kJ for 3 MW RF power. However, the radiation was more likely to increases quickly while in H-mode leading to a back L-H transition. So, either the new boronization did not do the job of covering the Mo properly in the right places or, we are running into problems with Mo sources (melting?) in areas different than from 1050610. As an aside - the gate valves were closed from shot 1 onward. In most shots before shot 9 the walls were fueling (14.3 Torr-l on shot 2, 2 on shot 5,6). A series disruptions (up through shot 8). Finally in shot 9 the wall pumping normally seen at these densities (12-14 Torr-l) was observed. Wall pumping as high aaas 19 Torr-l was observed on shot 11. Details are given under the RGA topic. |
| Physics Operator Summaries |
| Entered: Jun 23 2005 11:21:23:410AM |
| Author: Earl Marmar |
| Physop Summary
1050622 MP417 - Boronization evaluation SL - Lipschultz This was a half run, to evaluate the boronization from the previous evening. Because of a problem with ECDC, the run start was delayed until 1:00 pm, in order to have 4 hours of ECDC in He and 1 hour in D2 after boronization and before the run. The machine ran well, with very reliable startup. The only segment 1 changes were to reduce the fill pressure after the first shot, and after a couple of disruptions. On many shots, there appeared to be something heating near the lower divertor, visible on both wide 1 and wide 2. Matt Reinke reported significant Mo levels throughout the day, although a number of shots had decent H-modes (H_89>1,5) at ~3 MW of RF power. On shot 16, we moved the x-point in about 1 cm, to see if this would help with the hot spot; the shot disrupted at .84 s. There was one delay during the run, due to a full computer disk, which also caused a loss of some data from shot 7. Scorecard: Plasmas 16 Fizzles 0 Duds 0 Total cycles 16 |
| Session Leader Comments | |||
| Jun 22 2005 01:07:14:230PM | 1050622001 | Bruce Lipschultz | Shot went fine.
Pre-H-mode density needs to be lowered to 0.8. J port did nto make it. Will also try and fix the ssep dropping to close to DN. |
| Jun 22 2005 01:28:32:077PM | 1050622002 | Bruce Lipschultz | More RF power. L-H transition driven by radiation and then plasma goes back into H-mode (1.04 s) with less radiation and H=1.7.
Pre-H-mode density of 0.8 as requested. SSEP variation fixed. |
| Jun 22 2005 01:40:01:450PM | 1050622003 | Bruce Lipschultz | Disruption shortly after RF comes on - rather large amount of Mo - kills plasma |
| Jun 22 2005 01:52:16:373PM | 1050622004 | Bruce Lipschultz | RF trips on E seemed to knock the plasma out of H-mode. Confinement poor. |
| Jun 22 2005 02:07:21:950PM | 1050622005 | Bruce Lipschultz | Still problems with E tripping. Confinement starts out good but then degrades. Reinke says that Mo appears to be the radiator. |
| Jun 22 2005 02:22:17:717PM | 1050622006 | Bruce Lipschultz | Lowered E power a bit. Stayed on a bit longer. H factors ~ 1.6-1.7 but the radiation keeps rising and tripping the plasma back out of H-mode. |
| Jun 22 2005 02:45:44:887PM | 1050622007 | Bruce Lipschultz | E doing better. But data system problem - disks full. Waiting for that to clear before going on.
What little we can see of the shot indicates that it is pretty similar to shot 6 - radiation increasing killing the H-mode. |
| Jun 22 2005 03:45:40:087PM | 1050622008 | Bruce Lipschultz | E power lowered further. H-modes being killed by radiation.
Shot disrupted at rampdown - maybe due to pellet. |
| Jun 22 2005 03:47:43:790PM | 1050622009 | Bruce Lipschultz | No difference - still getting killed by radiation. |
| Jun 22 2005 03:49:27:573PM | 1050622010 | Bruce Lipschultz | Ar gas turned on - 40 ms pulse.
Steadier RF - still problems with radiation leading to L-H transition. |
| Jun 22 2005 03:50:38:213PM | 1050622010 | Bruce Lipschultz | Ar gas turned on - 40 ms pulse.
Steadier RF - still problems with radiation leading to L-H transition. |
| Jun 22 2005 04:00:06:027PM | 1050622011 | Bruce Lipschultz | J tripped - L-mode.
MHD antenna being used. |
| Jun 22 2005 04:25:30:823PM | 1050622012 | Bruce Lipschultz | Steadier H-mode. H-factor for 1st H-mode high but radiation rising and L-H transition follows. The second H-mode has low radiation but poorer confinement (dropping from 1.7ish to 1.4). |
| Jun 22 2005 04:33:19:883PM | 1050622013 | Bruce Lipschultz | J tripped again - short H-mode at end (essentially Ohmic). |
| Jun 22 2005 04:45:15:713PM | 1050622014 | Bruce Lipschultz | Fairly steady confinement - H=1.4-1.5 with one drop out of H-mode after the radiation rises at 1 second. |
| Jun 22 2005 05:17:59:073PM | 1050622014 | Bruce Lipschultz | Wtot ~ 160 kJ with the nominal 3 MW.
H-factors ~ 1.5 before radiation creeps up. |
| Jun 22 2005 05:20:17:353PM | 1050622015 | Bruce Lipschultz | nl04 ~ 0.85e20.
Wtot ~ 150 - 160 kJ with the nominal 3 MW. H-factors ~ 1.45-1.55 before radiation creeps up. |
| Jun 22 2005 05:24:50:430PM | 1050622016 | Bruce Lipschultz | nl04 ~ 0.85e20.
disruption at 1 second. Had moved the x-point in to get the strike point off of the divertor plate. This was based on the concern that there may be a melted spot on the divertor that was spewing Mo. Unfortunately, this move may have caused more problems (althrough we did this with no problem on Monday). |
| Physics Operator Comments | |||
| Jun 22 2005 01:13:16:200PM | 1050622001 | Earl Marmar | load shot 1050610024
load segment 1 from 1050621003 reduce prepuff to 20 msec plasma |
| Jun 22 2005 01:27:21:747PM | 1050622002 | Earl Marmar | gate valves closed for this shot
reduce prepuff by 2 msec (to 18 msec) tweak zxu and zcur to try to keep ssep from drifting toward DN after 1.2 seconds nl_04 target to 0.8e20 plasma 174 kJ at 3 MW SSEP much steadier |
| Jun 22 2005 01:32:22:653PM | 1050622003 | Earl Marmar | no pcs changes
gate valves closed for this shot plasma big increase in radiated power at .84 s, disrupt at .88 |
| Jun 22 2005 01:57:30:030PM | 1050622004 | Earl Marmar | lower the prepuff by 1 msec
plasma multiple H-modes, some RF trips |
| Jun 22 2005 02:01:21:077PM | 1050622005 | Earl Marmar | no pcs changes
plasma 150 kJ with RF bouncing between 2 and 3 MW |
| Jun 22 2005 02:17:51:260PM | 1050622006 | Earl Marmar | no pcs changes
plasma |
| Jun 22 2005 02:32:38:060PM | 1050622007 | Earl Marmar | increase nl_04 target to .9e20
plasma many DAC problems after the shot |
| Jun 22 2005 03:25:14:123PM | 1050622008 | Earl Marmar | no pcs changes
plasma Interferometer jumped a fringe early, gas turned off Density was lower than we wanted Li pellet at 1.5 s, then disrupted |
| Jun 22 2005 03:39:04:590PM | 1050622009 | Earl Marmar | no pcs changes
plasma |
| Jun 22 2005 03:38:53:307PM | 1050622010 | Earl Marmar | argon on for 40 msec pulse, 1 psi
nl_04 target to 1.05e20 |
| Jun 22 2005 04:02:04:150PM | 1050622010 | Earl Marmar | no pcs changes
plasma L-mode; Prf ~ 0.6 MW |
| Jun 22 2005 04:21:26:463PM | 1050622012 | Earl Marmar | no pcs changes
plasma much steadier RF Decent H-mode |
| Jun 22 2005 04:25:51:650PM | 1050622013 | Earl Marmar | no pcs changes
plasma little RF power H-mode late |
| Jun 22 2005 04:41:19:573PM | 1050622014 | Earl Marmar | nl_04 target to 9.3e19
plasma Much better RF; decent H-mode |
| Jun 22 2005 05:01:14:650PM | 1050622015 | Earl Marmar | no pcs changes
plasma |
| Jun 22 2005 05:03:55:760PM | 1050622016 | Earl Marmar | RXL moved in ~1 cm (intention is to move the strike onto the floor)
plasma early disruption (.83 seconds) |
| Engineering Operator Comments | ||||
| Shot | Time | Type | Status | Comment |
| 1 | 12:57:51:763PM | Plasma | Ok | |
| 2 | 01:14:07:933PM | Plasma | Ok | |
| 3 | 01:27:39:967PM | Plasma | Ok | |
| 4 | 01:40:07:717PM | Plasma | Ok | |
| 5 | 01:52:47:420PM | Plasma | Ok | |
| 6 | 02:11:36:137PM | Plasma | Ok | |
| 7 | 02:24:32:340PM | Plasma | Ok | |
| 8 | 03:16:18:273PM | Plasma | Ok | |
| 9 | 03:29:34:057PM | Plasma | Ok | |
| 10 | 03:42:18:947PM | Plasma | Ok | |
| 11 | 03:55:25:837PM | Plasma | Ok | |
| 12 | 04:08:39:260PM | Plasma | Ok | |
| 13 | 04:21:19:180PM | Plasma | Ok | |
| 14 | 04:34:04:840PM | Plasma | Ok | |
| 15 | 04:47:09:713PM | Plasma | Ok | |
| 16 | 05:02:02:323PM | Plasma | Ok | |