| Miniproposals | ||||||||||
|
| Operators | |
| Session leader(s): | Steve Golovato |
| Physics operator(s): | Steve Horne |
| Engineering operator(s): | Frank Silva,Vinny Bertolino |
| Engineering Operator Run Comment |
| Bertolino/Silva/Horne |
| Session Leader Plans |
| Physics Operators Plans |
| Session Leader Summaries |
| Entered: Jul 7 2004 03:49:12:180PM |
| Author: To Be Determined |
| run summary - 950203 --------------------- SL: golovato PO: horne EO: silva/bertolino Goals- (1) hydrogen minority scan 5% H (mixture in plenum) 10% H 20% H use H/D from pcx, watch for wall equilibration over several shots at each mixture. two densities at each mixture (nl_04 = 1.1 and 0.8e20 cm-2). (2) outer gap scan at fixed conditions. go from 5 to 30 mm. We started by loading shot 950201032, which had breakdown on the Bt ramp, and got plasma on shot 3. We accomplished most of the first goal but did not get to the second goal at all. The actual hydrogen concentrations in the gas puffing plenum were 7.3%H, 12.8%, and 22.3%. The two densities we used at each concentration were nl_04= 1,1e20 cm-2 and 0.7e20 cm-2. Which shots had which condition are indicated in the table below with the best shot(s) at each condition in parentheses: 7.3% 12.8% 22.3% ----- ----- ----- 1.1e20 cm-2 ==> 3-12,15 16-19 25-27 (15) (17,19) (27) 0.7e20 cm-2 ==> 13-14 20-22 28-29, 31-35 (13) (20) (34,35) Generally it can be said that the heating, as measured by the increase in stored energy, decreased with increasing concentration and with increased density. There was also a significant increase in the interaction between the antennas as the H concentration was increased. This may be due to changes in heating and changes in wave propagation. For example, the cut-off and resonance in the plasma core become more separated as the minority cncentration is increased. This may account for weaker heating and for standing waves between the antenna and the cutoff, increasing the interaction between the antennas. Sawteeth were lower frequency and clearly visible in the rf power signals at higher concentration. They could be in phase with core sawteeth or inverted, sometimes the antennas showed opposite sawtooth phases, sometimes one antenna showed both phases on the same shot. It was very strange. Shot 18 had E-port only and shots 21,25,26,27,28,31,32 had D-port only. Many shots had one interruping (usually E-port) when the other came on. We did manage, barely, to get a good shot above 2 MW at each density and concentration. H-modes were clearly seen at both densities for the lowest concentration, but were less clear at higher concentrations. There appeared to be some dithering on some shots when we managed to have both antennas running and power above 2.5 MW. It seemed this was around the threshold and if we hit it, we would pop into H-mode (see shot 8 for example). Shot 27 had a moly blowoff experiment at 1 sec. It did seem that having breakdown on the TF ramp reduces the cooldown time between shots and we get more shots per day. The session leader shot-to-shot summary can be found in the logbook under the session_leader topic. Details on technical difficulties can be found in the physics operator summary. The shot summary was: 30 plasmas 5 fizzles 1 dud |
| Physics Operator Summaries |
| Entered: Jul 7 2004 04:36:53:100PM |
| Author: To Be Determined |
| Run 950203, RF heating, MP59? Golovato, Horne, Silva, Bertlino. Plan was to take data with both transmitters, at various H/D ratios, at "high" and "low" density. This was done, with moderate success. The RF data is complicated; see the session leader log for details. From the wirehead point of view the run was interesting. We used Ian's latest startup, on the TF ramp. This startup seems to be at least as robust as our earlier startup; the decreased TF heating probably gives us an extra shot or two per run. The two fizzles in the middle of the run were probably related to increasing h/d ratio; there is some evidence that if h/d increases, fill should be reduced. The RF feedback signal was put on wire 12; the RF group needs to do a little more work before we can test it. I tried the segment 3 rampdown but wasn't terribly successful. The problem of matching up segments needs to be thought about more. The main difficulty is with the density feedback; we seem to tolerate positional mismatches. Low density rampdowns seem to require extra gas; high densities require that the gas be turned off. ==== Statistics -- Earl's record still stands. One wonders why he was logged into physop. 36 attempts, 30 plasmas, 5 fizzles, one dud. ======= Log ======= Load shot 950201032, change commutation resistors and timing appropriately. 1 fill at 2.2 e -5 fizzle 2 fill 1.4 Fizzle 3 try scatterplot against Ian's shots 31 - end. br looks too positive. Reduce by -.5 mt. PLASMa 4 repeat,plasma move x point 2 mm down, 2 mm out to correct inner strike point for shot 5. 5 xpoint moved, but not enough. Do that change again for 6. 6 That worked 7. Repeat; Xpoint not perfect yet. Do another (2,2) mm tweak 8. Plasma. (10:30) RF, HMODES 9 PLASMA Hmodes again. 10 Ho Hum. See the session leader log for all the exciting RF results. X-point looks better now. Could still be moved down a tad. The RF feedback signal begins to look real. We added a signal rf_load_e to wire 13, but didn't load it yet. Signal name appeared in PCS in lower case, implying no gain. This is right. The p-to-v expression in the hybrid is a gross estimate based on shot 9; looks like -10. ohms/volt, roughly. 11 Plasma. Mike F can't tweak the offset out of the rf loading signal -- the bira is either broken or misconnected. 12 Plasma. Lower density next shot -- 8.e19 nl_04. 13 Disrupted late? ef1 lower is sick -- crowbarred. Nice RF shot. Lots of moly -- low density cause it? rf loading signal does appear on aout scope. 14 disrupted on rampdown; raise density for next shot -- back to 12. 15 Raising density fixed the disruption. For next shot, change ratio to 2 lb H/18 lb D 16 Plasma. There's early moly. Fill has been at 1.4 till now. Next shot try 2.0 17 That seems to have worked -- less moly early. good rf shot. There is an unesthetic z oscillation from .35 to .45 sec. Drop Z fast P gain to 4 there. 18 Low rf power. The z gain tweak worked; move it to .35 next shot. 19 The z oscillation is gone. Next shot, density back to 7.e19. Extend density flattop to 1 sec; hope that cures the rampdown disruption. Disrupted at 1.1 sec. Try Really holding the denssity up. 20 Nice RF shot. Disruption still there; it trips oh2L. Try holding rcur out, clearin out at rampdown. Also reduce slow Z gain at t=1 sec to protect oh2 supplies. 21 That worked -- no disruption. Lot's of moly injections. Looks like th inner str4ike point is on the floor early -- move rxl more negative then. The equiblirium is nearly double diverted; raise zxu two cm. Don't load these till after shot 22. For shot 22, just raise the fill to 2.2e-5. 22 Plasma. Much less moly. Load the above changes for 22. change plenum to 4 lb h2, 16 lh d2. Raise density back to 1.1e20. Drop fill back to 2.0e-5 23 fizzle. Try raising the fill to 2.3e-5 24 Fizzle. It turns out that Earl Marmar is logged onto Physop. Is this a coincidence? Try 1.5 e-5 on fill. 25 That worked. No changes for next. 26 ok. Try switching in the diverted rampdown. Make no effort to match the boundary -- don't even look at it. 27 Worked; shot has deliberate moly injection at 1.0 sec. Next shot -- .7 e20. 28 Problems at the start of segment 3 -- otherwise ok. Make these changes in segment 3 -- (diverted rampdown) slow zcur gain to .5 draw zcur to zero 29 Nasty disruption at 1.0 sec + change. Need to rethink segment 3 rampdown. Turn it off for now. 30 Fizzle. h-alpha says it bounced. Rcur says inside; the ece scope sees something -- 3'rd harmonic? moving in. Drop the fill to 1.2e-5. 31 Plasma, disrupted at rampdown. Try Raising density first, then dropping it. Also adjust early gas to deal with moly injections. 32 Looks ok. Got the rampdown. 33 Also ok. Try making density changes in segment 3 as in segment 2 for next. 34 Disruption again. Segment 3 off for next. 35 Ramps down ok. 36 Dud. BR is screwy. No obvious reason except it's the last shot of the day. ========== done. Golovato contributes beer. ======== |
| Session Leader Comments | |||
| Feb 3 1995 08:52:07:270AM | Steve Golovato | run 950203 - icrf heating
goals: (1) hydrogen minority scan 5% H (mixture in plenum) 10% H 20% H use H/D from pcx, watch for wall equilibration over several shots at each mixture. two densities at each mixture (nl_04 = 1.1 and 0.8e20 cm-2). (2) outer gap scan at fixed conditions. go from 5 to 30 mm. starting with shot 950201032, which had breakdown on Bt ramp. | |
| Feb 3 1995 08:52:35:390AM | 950203001 | Steve Golovato | 950203001 - fizzle.
|
| Feb 3 1995 08:52:44:500AM | 950203002 | Steve Golovato | 950203002 - fizzle.
|
| Feb 3 1995 09:15:39:500AM | 950203003 | Steve Golovato | 950203003 - plasma. plenum filled to 1.44# H, 18.32# D => 7.3% H
1.2MW on D , E still mistuned. |
| Feb 3 1995 09:31:42:640AM | 950203004 | Steve Golovato | 950203004 - plasma. 1.25MW-D, E still mistuned.
|
| Feb 3 1995 09:47:23:320AM | 950203005 | Steve Golovato | 950203005 - plasma. 1.4MW-D , 0.6MW-E
|
| Feb 3 1995 10:01:51:940AM | 950203006 | Steve Golovato | 950203006 - plasma. 1.3MW-D, 1MW-E. rf running from .7-.9 sec.
something flew off e-port antenna, both transmitters interrupted. |
| Feb 3 1995 10:23:08:190AM | 950203007 | Steve Golovato | 950203007 - plasma. 1.3MW-D, .85MW-E. sawteeth showing up strongly
on rf power signals at higher H concentration. |
| Feb 3 1995 10:40:06:090AM | 950203008 | Steve Golovato | 950203008 - plasma. 1.3MW-D and interrupting. 1.65MW-E with peaks
up to 2MW. Antennas seem to be interating strongly today. |
| Feb 3 1995 10:40:41:880AM | 950203008 | Steve Golovato | 950203008 - 3 H-modes, d interrupts at each.
|
| Feb 3 1995 10:54:04:690AM | 950203009 | Steve Golovato | 950203009 - plasma. D-port ran at 1.4MW, tuned intermediate between
L and H- mode, ran throughout. Eport crowbarred at beginning of H-mode when power at first dropped and then shot up to 2MW, was programmed for roughly 1,5MW. |
| Feb 3 1995 11:12:21:400AM | 950203010 | Steve Golovato | 950203010 - plasma. much like shot 9, E lost at h-mode transition.
E power starts lower but rises in h-mode then interrupts. D-1.4MW. |
| Feb 3 1995 11:28:06:090AM | 950203011 | Steve Golovato | 950203011 - plasma. E-port ran a little in t h-mode this time before
interrupting. power varies substantially although programming is flat. loading varies by about 1 ohm (5.3 to 4.3), power almost doubles increasing as loading decreases. loading drops an additional ohm in h-mode. |
| Feb 3 1995 11:41:58:000AM | 950203012 | Steve Golovato | 950203012 - plasma. both interrupted during h-mode. d-port ran at
1.4MW, e-port ran from 0.8-2MW. |
| Feb 3 1995 12:05:19:650PM | 950203013 | Steve Golovato | 950203013 - plasma. density programming reduce from 1.1 to .7e20.
clean rf shot, 1.3MW on D and 1MW on E. dithering H-mode. |
| Feb 3 1995 12:27:40:180PM | 950203014 | Steve Golovato | 950203014 - plasma. d-port 1.3MW drops to .84 in h-mode. e-port at
1.3, rises to 1.8 in h-mode (net power constant), then trips. |
| Feb 3 1995 12:35:28:470PM | 950203015 | Steve Golovato | 950203015 - plasma. density back to 1.1e20. rf ran cleanly,
one interupt on d-port. d-port 1.35MW, e-port 1.1MW ran up to 1.6 at begining of h-mode but did not trip. |
| Feb 3 1995 12:51:30:370PM | 950203016 | Steve Golovato | 950203016 - plasma. raised H fraction to 12.8%, still at 1.1e20.
d-port 1.3MW, e-port .7MW. both tripped early. no h-modes. d-port had fpa screen overcurrent trip. |
| Feb 3 1995 01:06:28:660PM | 950203017 | Steve Golovato | 950203017 - plasma. good rf shot, d-port 1.3MW, e-port about 1MW.
d-port screen trip after programmed step up to about 1.5MW. no h-modes at this higher H concentrations, heating weaker.. |
| Feb 3 1995 01:21:47:400PM | 950203018 | Steve Golovato | 950203018 - plasma. no d-port power, wasn;t reset from last shot.
e-port power on;y .6-.7MW. |
| Feb 3 1995 01:25:09:770PM | 950203019 | Steve Golovato | 950203019 - plasma. good rf shot. d-port 1.3MW stepping to 1.45 MW.
e-port 0.9 to 1.2 MW. no h-mode. |
| Feb 3 1995 01:40:04:330PM | 950203020 | Steve Golovato | 950203020 - plasma. lower density, 0.7e20 from 1.1e20.
d-port 1.25 to 1.35 MW, e-port .9 tp 1.1MW. e-port pulse up in power at each sawtooth crash and we pop in to h-mode. casue and effect unclear but we are clearly sitting close to threshold. heatng better. |
| Feb 3 1995 01:48:15:270PM | 950203021 | Steve Golovato | 950203021 - plasma. ragged, lots of injections, e-port tripped out.
|
| Feb 3 1995 02:02:08:590PM | 950203022 | Steve Golovato | 950203022 - plasma. both transmitters tripped out early.
|
| Feb 3 1995 02:10:43:670PM | 950203023 | Steve Golovato | 950203023 - higher H concentration, about 20%. back to nl04=1.1e20.
fizzle. |
| Feb 3 1995 02:30:17:600PM | 950203024 | Steve Golovato | 950203024 - another fizzle.
|
| Feb 3 1995 02:42:56:690PM | 950203025 | Steve Golovato | 950203025 - H/(H+D) in plenum 22.3%. plasma again. trick was lower
fill with high H concentration. d-port ran well, 1.2 to 1.3MW. e-port tripped out early. |
| Feb 3 1995 02:52:06:820PM | 950203026 | Steve Golovato | 950203026 - moly blow-off (on purpose) at 1 sec, no moly monitor
this shot. actually will be next shot, jt forgot to open gatevalve. plasma. d-port only again. |
| Feb 3 1995 03:01:25:300PM | 950203027 | Steve Golovato | 950203027 - moly blow-off (on purpose) at 1 sec, no moly monitor
this shot. plasma, good rf shot. d-port 1.2MW, e-port 1.3 to 1.9 MW. may be dithering. |
| Feb 3 1995 03:16:05:580PM | 950203028 | Steve Golovato | 950203028 - plasma. d-port 1.05-1.5MW, e-port crowbarred early.
|
| Feb 3 1995 03:36:30:430PM | 950203029 | Steve Golovato | 950203029 - plasma. no e-port again.
|
| Feb 3 1995 03:51:38:890PM | 950203030 | Steve Golovato | 950203030 - fizzle.
|
| Feb 3 1995 04:05:29:110PM | 950203031 | Steve Golovato | 950203031 - plasma. no e-port again.
|
| Feb 3 1995 04:13:34:490PM | 950203032 | Steve Golovato | 950203032 - plasma. no e-port again, seems to trip out when d-port
utrns on. try delaying d-port turn on till 800ms. |
| Feb 3 1995 04:24:34:530PM | 950203033 | Steve Golovato | 950203033 - plasma. e-port again ran till d-port came on, ran
together for 30ms at high power. antennas seem to be influenced by each other in some perverse way. adding attenuation to e-port RP to reduce sensitivity of arc detector. |
| Feb 3 1995 04:47:47:620PM | 950203034 | Steve Golovato | 950203034 - plasma. e-port ran better but there's still interactions
between the antennas. |
| Feb 3 1995 04:50:57:560PM | 950203035 | Steve Golovato | 950203035 - plasma. e-port ran, d-port tripped early. next
shot we'll get them both. we better, it's the last shot. |
| Feb 3 1995 05:02:24:110PM | 950203036 | Steve Golovato | 950203036 - dud.
|
| Physics Operator Comments |
| Engineering Operator Comments | ||||
| Shot | Time | Type | Status | Comment |
| 1 | 08:27:31:660AM | Plasma | Ok | no faults first shot 08:30 no plasma |
| 2 | 08:39:15:840AM | Plasma | Ok | no faults no plasma |
| 3 | 09:00:32:270AM | Plasma | Ok | no faults plasma |
| 4 | 09:19:08:000AM | Plasma | Ok | no faults plasma |
| 5 | 09:33:40:030AM | Plasma | Ok | no faults, plasma |
| 6 | 09:54:06:980AM | Plasma | Ok | no faults |
| 7 | 10:09:43:210AM | Plasma | Ok | no faults, plasma |
| 8 | 10:26:27:230AM | Plasma | Ok | no faults, plasma |
| 9 | 10:42:42:460AM | Plasma | Ok | no faults, plasma |
| 10 | 10:57:08:070AM | Plasma | Ok | no faults, plasma |
| 11 | 11:12:01:800AM | Plasma | Ok | no faults, plasma |
| 12 | 11:28:07:340AM | Plasma | Ok | no faults, plasma |
| 13 | 11:45:45:300AM | Plasma | Ok | comm fault ef1L, before plasma disruption |
| 14 | 12:04:24:790PM | Plasma | Ok | no faults, plasma |
| 15 | 12:21:07:060PM | Plasma | Ok | no faults, plasma |
| 16 | 12:36:23:440PM | Plasma | Ok | no faults, plasma |
| 17 | 12:49:33:010PM | Plasma | Ok | no faults, plasma |
| 18 | 01:00:50:510PM | Plasma | Ok | no faults |
| 19 | 01:13:06:400PM | Plasma | Ok | no faults |
| 20 | 01:27:19:800PM | Plasma | Ok | disruption induced comm faults |
| 21 | 01:40:21:420PM | Plasma | Ok | no faults |
| 22 | 01:54:17:450PM | Plasma | Ok | no faults |
| 23 | 02:09:03:930PM | Plasma | Ok | no faults |
| 24 | 02:20:13:820PM | Plasma | Ok | no faults |
| 25 | 02:30:43:710PM | Plasma | Ok | no faults |
| 26 | 02:42:11:330PM | Plasma | Ok | no faults |
| 27 | 02:54:47:590PM | Plasma | Ok | no faults |
| 28 | 03:09:22:900PM | Plasma | Ok | no faults |
| 29 | 03:21:15:110PM | Plasma | Ok | no faults |
| 30 | 03:34:03:460PM | Plasma | Ok | no faults |
| 31 | 03:49:06:760PM | Plasma | Ok | no faults |
| 32 | 04:03:52:080PM | Plasma | Ok | no faults |
| 33 | 04:14:39:650PM | Plasma | Ok | no faults |
| 34 | 04:30:08:830PM | Plasma | Ok | no faults |
| 35 | 04:45:28:630PM | Plasma | Ok | no faults |
| 36 | 04:59:11:340PM | Plasma | Ok | no faults |