| Miniproposals | ||||||||||
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| Operators | |
| Session leader(s): | Yuichi Takase |
| Physics operator(s): | Steve Golovato |
| Engineering operator(s): | Joe Daigle |
| Engineering Operator Run Comment |
| RF run |
| Session Leader Plans |
| Physics Operators Plans |
| Session Leader Summaries |
| Entered: Jul 7 2004 03:49:09:290PM |
| Author: To Be Determined |
| 931020 SL: Takase PO: Golovato EO: Daigle RF run Major objective is to push power. We will be searching for a condition in which the impurity release is minimized. We will be scanning the density, moving the limiter/antenna positions, etc. Start with R_lim=92cm, R_ant=94cm, D puff from A-side only. Halpha filter on tangential TV. Shot 001 dud (diamagnetic baseline shot) 002 good shot, 140kW, nel ramps to 9e19 003 good shot, 230kW 004 good shot, 320kW, nel ramps to 8e19 005 disrupted @.78sec, P_max=450kW (something fell from the antenna) small H puff from B-side-upper 006 good shot, 300kW, nel ramps to 8e19 007 good shot, 700kW peak, nel ramps to 8e19 008 good shot, 750kW peak, higher baseline (>250kW for .5sec) 009 good shot, 750kW peak, disrupted at 1.1sec 010 disrupted at .87sec, 750kW peak H puff (H wasn't getting in on previous shots) 011 disrupted at .28sec 012 disrupted at .88sec, 750kW peak 013 disrupted at .88sec, 800kW peak 014 disrupted at .55sec, 900kW peak 015 disrupted at .86sec, 700kW peak 016 disrupted at .39sec, 900kW peak 017 disrupted at .81sec, 700kW peak 018 disrupted at .71sec, 1000kW peak 019 disrupted at .34sec, 500kW peak 020 R_lim=93cm, R_ant=94cm, disrupted at .80sec, 600kW peak 021 disrupted at .21sec 022 disrupted at .28sec 023 disrupted at .43sec, 750kW peak 024 R_lim=93cm, R_ant=95cm, disrupted at .95sec, 450kW peak 025 good shot, disrupted at .97sec, 450kW peak 026 good shot, disrupted at .96sec, 500kW peak transmitter problem 027 no rf shot, good shot 028 TF baseline shot We have made good progress in raising the injected rf power. By shot 008, 750kW peak power has been injected with over 250kW maintained for over .5sec, and without disruption. Progress beyond this power level for longer pulses was made difficult by the change in tuning as the plasma evolves during a shot. The tuning change results in a sudden increase of injected power, followed by a disruption. On shot 018, the injected power momentarily exceeded 1MW, but ended in a disruption. Later in the run, approximately 0.5MW was injected for 0.4sec. These shots did not disrupt until the current ramp-down phase, which is well after the rf pulse. The rf transmitter developed a major problem (the bypass capacitor in the final cavity shorted) after shot 026, and the run was aborted at 5:00pm, after taking a no-rf shot and a TF-only baseline shot (today's run was scheduled to last till 7:00pm). The radiated power was well behaved throughout the rf pulse, except immediately before a disruption. A clear sign of heating has not been observed so far, and it is not clear where the rf power is going. We will continue to explore heating next week after the transmitter has been fixed. |
| Physics Operator Summaries |
| Entered: Jul 7 2004 04:36:50:520PM |
| Author: To Be Determined |
Physics Operator Log - 931020 - Golovato ---------------------------------------- 2 hrs ecdc in d2 before run. Starting with shot 14 of yesterday. Plasma shape matches antenna better than shot 1, gas is all from a-side. Start fill at 1.3e-5, as yesterday. Limiter at 92cm, antenna at 94cm. H_alpha filter on tv view of antenna and limiter gives bright, clear look at them during shot. RF "assisted" startup enabled. Shot Log: 1 - Dud. No obvious problems. 2 - Raised fill to 1.4e-5. Pretty shot, no disruption, 850ka, ran to 1.3s. 3 - Another beauty. Raising rf power each shot. Peak about 200kw this shot. 4 - Good shot. Peak rf 300kw. 5 - Adding H2 puff, 50ms, 40v at 400ms (with quick initial peak at 60v). UFO blew off of antenna, came from upper right tile, could be from a probe mounted behind tile at this location. Otherwise good looking shot, until disruption at 750ms, rf near 400kw. 6 - Repeat. Moving TF inversion from 1s to 0.8s to speed recool. TF is the slowest to recool, determines the shot cycle. Good clean shot now that we've removed an imperfection from the antenna. 7 - Tweaked pulsed D2 raising slightly between 100-300ms, nl flattening more and more each shot just before OH zero crossing, where it always jumps up and continues ramping until 1s. 700kw peak rf power. 8 - Extended H2 puff to 100ms. Another good shot, peak power about 600kw, 280kw pedestal for 500ms. 9 - Enabled Ar puff. Increased H2 puff to 60v from 400-500ms. CX still doesn't see H signal. Disrupted a little early, at 1.1s. 10 - H2 puff was at the wrong voltage, never really puffed. Now hav 100v from 400-420ms (Goetz reminded me that the last time we ran, we could just see a 15ms, 100v puff). Good but disrupted at 870ms. Problems brewing, density ramping up fast at beginning, then falling back at 200ms, then rising again to end of shot, used to be montonic. Also, current is falling off, not reaching programmed value and falling once rf power is above 400kw, eventually disrupting early. No changes made yet but we may have to deal with this soon. 11 - Increased H2 puff to 40ms. Disrupted very early. Density ramped fast to 1e20, current didn't ramp normally, was only around 450ka disrupted at 280ms. Shot looked bad from start. Zmeter digitizer did not init, lost data for several spectroscopy diagnostics. 12 - Fill to 1.3e-5, some trivial tweaks to D2 puff. Disrupted at 880ms. 13 - H2 puff 400-700ms at 30v with 100v turnon pulse. CX sees H2 but mainly during puff. Looked the same, disrupted at 880ms. 14 - Disrupted at 550ms. rf hit 1MW for about 2ms. 15 - Raised H2 puff to 35v. Disrupted at 850ms. 480ms, 500-600kw rf pulse. 16 - Raised H2 puff to 40v. This may be too much. We'll turn it off for for a few shots and see how the levels decay. Disrupted early at 380ms. rf came on hard at 330ms, current stopped ramping. 17 - Ran longer, disrupted at 830ms. 500-600ms for 0.5s. 18 - Turned off H2 for a few shots to see effect on CX signals. Fill to 1.4e-5. Trying to reduce knee in current rise at 80ms. Disrupted at 700ms. OH1 not following demand near end just before disruption, getting to negative current limit of 16ka. Current ramp better with higher fill. 19 - Lowered early puff from 40v to 38v to reduce fast early density ramp. Early disruption, 350ms. Move rf start later to let current reach flattop. 20 - Limiter moved back 1cm to 93cm, rf start 50ms later, early gas increased but not all the way to previous setting. Better shot, disrupted at 800ms. 21 - Increased OH1 limits to -18ka/+21ka from -16ka/+20ka. Disrupted very early, 200ms. 22 - Lowered fill to 1.3e-5, fiddled with early puff, but no important change. Another early disruption at 270ms, during OH1 crossover. 23 - Lower fill to 1.2e-5. Also lower early gas. Better, longer, but dirupted right after rf came on, at 425ms. 24 - Moved antenna out to 95cm from 94cm, lowered power. Also tweaked early gas up. Better shot, disrupted at 940ms, after rf pulse. 25 - Raised rf power. Disrupted at 940ms again, may be OH1 current limit again. Remember negative is positive and vice versa. Seeing evidence of heating of D on CX and neutron data!!!!! 26 - Raised OH1 limit to -20ka from -18ka. Disrupted at 960ms. 27 - Dropped off puff after 500ms to 0 at 800ms, bringing down density both to get scan and increase CX flux. Also supposedly small divertor He puff at 500ms should show up at about 700ms. No rf shot. Good shot ran to 1.3s. Transmitter FPA grid bypass capacitor shorted. Requires removal of cavity to repair. Run rf is over. 28 - Baseline shot for diamagnetic loop. No fill, no plasma, TF only. Post-run Comments ----------------- Scorecard: 28 shots - 1 dud, 1 baseline shot, 26 plasmas 3 plasma shots (11,21,22) disrupted early (<300 ms), before rf came on at high power. TF inversion was moved from 1 sec to 800 ms after shot 5 to speed up the shot cycle. TF cooling is generally the pacing item. We did no careful analysis to see if it had the desired effect but my impression was that it did. That is, either IGOR or I seemed to set the cycle time thereafter. We were apparently getting a sharkfin (detached plasma) very early in the shots which caused the density behavior seen shot 10 for example, where nel rises fast and the falls off at 200 ms, then rises again after OH1 crossover. The sharkfin appears to be killed when the plasma moves out and limits on the outboard limiter during crossover. Goetz says that by tweaking the early gas the density ramp can be made monotonic and smooth, if it's important to you. Early shots today had monotonic density ramps, though they all slowed around OH1 crossover. ECE saw evidence of nonthermal behavior early in the shot, on shot 17 in particular, which correlates with a fast initial rise and then a knee in the current ramp at about 100 ms. This was "corrected" by raising the fill from 1.3e-5 to 1.4e-5. The very early disruptions, which also had slow current ramps (maybe almost a fizzle) were corrected by lowering the fill, as after shot 11 and after shots 21 and 22. The fill was down to 1.2e-5 after shot 22 and good plasmas were obtained thereafter. The early gas was played with and ended up a little lower than we started with. Potential Future Problem: The outboard limiters were not designed to be the main limiter. We may get into trouble if it has to be on every shot for 50-70 ms during OH1 crossover. I don't know if this will always be there, but when the stored energy in the plasma gets substantially higher in the future, the limiters (there will be two of them with the two-strap antennas) may not take it. |
| Session Leader Comments | |||
| Oct 20 1993 09:20:45:840AM | Yuichi Takase | RF run
Push power We will search for a condition in which plasma can take high injected rf power. We will probably be scanning density and moving the antenna and limiter positions. | |
| Oct 20 1993 09:25:35:330AM | 931020001 | Yuichi Takase | Shot 001
Dud (diamagnetic baseline shot). |
| Oct 20 1993 09:26:47:350AM | 931020002 | Yuichi Takase | Shot 002
Good shot (140kW). |
| Oct 20 1993 09:39:47:460AM | 931020003 | Yuichi Takase | Shot 003
Good shot (230kW). nel = 6e19 - 9e19 (t = 0.3 - 0.9sec). Currently puffing D only from A side. R_lim=92cm, R_ant=94cm. |
| Oct 20 1993 09:58:11:520AM | 931020004 | Yuichi Takase | Shot 004
Good shot (320kW). nel = 6e19 - 8e19 (t = 0.3 - 0.9sec). Currently puffing D only from A side. |
| Oct 20 1993 10:35:13:980AM | 931020005 | Yuichi Takase | Shot 005
Disrupted @ 0.78sec (450kW). Something fell from the antenna. H puff from B-side-upper. |
| Oct 20 1993 10:36:07:130AM | 931020006 | Yuichi Takase | Shot 006
Good shot (300kW). TF ramp-down moved to 0.8sec. |
| Oct 20 1993 11:00:57:560AM | 931020007 | Yuichi Takase | Shot 007
Good shot (700kW peak). |
| Oct 20 1993 11:53:09:190AM | 931020008 | Yuichi Takase | Shot 008
Good shot (750kW peak). |
| Oct 20 1993 11:53:42:500AM | 931020009 | Yuichi Takase | Shot 009
Good shot (750kW peak). Disrupted at 1.1sec. |
| Oct 20 1993 11:54:26:730AM | 931020010 | Yuichi Takase | Shot 010
Disrupted at .87sec (750kW peak). |
| Oct 20 1993 11:55:21:120AM | 931020010 | Yuichi Takase | Shot 010
Fixed H puff programming (H wasn't getting in on previous shots). |
| Oct 20 1993 12:13:16:010PM | 931020011 | Yuichi Takase | Shot 011
Disrupted early at .28sec |
| Oct 20 1993 12:37:24:950PM | 931020012 | Yuichi Takase | Shot 012
Disrupted at .88sec, 750kW peak power. |
| Oct 20 1993 01:12:16:910PM | 931020013 | Yuichi Takase | Shot 013
Disrupted at .88sec, 800kW peak power. |
| Oct 20 1993 01:12:38:440PM | 931020014 | Yuichi Takase | Shot 014
Disrupted at .55sec, 900kW peak power. |
| Oct 20 1993 01:39:31:220PM | 931020015 | Yuichi Takase | Shot 015
Disrupted at .86sec, 700kW peak power. |
| Oct 20 1993 01:39:49:280PM | 931020016 | Yuichi Takase | Shot 016
Disrupted at .39sec, 800kW peak power. |
| Oct 20 1993 01:52:57:220PM | 931020017 | Yuichi Takase | Shot 017
Disrupted at .81sec, 700kW peak power. Disruption being caused by power variation due to loading variation. |
| Oct 20 1993 02:13:28:350PM | 931020018 | Yuichi Takase | Shot 018
Disrupted at .71sec, 800kW peak power. |
| Oct 20 1993 02:28:26:750PM | 931020019 | Yuichi Takase | Shot 019
Disrupted at .34sec, 500kW peak power. |
| Oct 20 1993 03:03:21:040PM | 931020020 | Yuichi Takase | Shot 020
R_lim=93cm (1cm back), R_ant=94cm (same). 600kW peak. |
| Oct 20 1993 03:17:50:470PM | 931020021 | Yuichi Takase | Shot 021
Disrupted at .21sec |
| Oct 20 1993 03:18:07:110PM | 931020022 | Yuichi Takase | Shot 022
Disrupted at .28sec |
| Oct 20 1993 03:34:17:770PM | 931020023 | Yuichi Takase | Shot 023
Disrupted at .43sec, 750kW peak |
| Oct 20 1993 04:02:20:780PM | 931020024 | Yuichi Takase | Shot 024
Good shot, disrupted at .95sec, 450kW peak. R_lim=93cm (same), R_ant=95cm (1cm back). |
| Oct 20 1993 05:07:25:950PM | 931020025 | Yuichi Takase | Shot 025
Good shot, disrupted at .97sec, 450kW peak. |
| Oct 20 1993 05:08:53:680PM | 931020026 | Yuichi Takase | Shot 026
Good shot, disrupted at .96sec, 500kW peak. Transmitter problem, needs to be repaired. No more rf today. |
| Oct 20 1993 05:09:32:640PM | 931020027 | Yuichi Takase | Shot 027
Good shot (no rf). |
| Oct 20 1993 05:10:02:360PM | 931020028 | Yuichi Takase | Shot 028
TF baseline shot. |
| Physics Operator Comments | |||
| Oct 21 1993 09:30:49:850AM | Steve Golovato | 2 hrs ecdc in d2 before run.
Starting with shot 14 of yesterday. Plasma shape matches antenna better than shot 1, gas is all from a-side. Start fill at 1.3e-5, as yesterday. Limiter at 92cm, antenna at 94cm. H_alpha filter on tv view of antenna and limiter gives bright, clear look at them during shot. | |
| Oct 21 1993 09:32:32:390AM | 931020001 | Steve Golovato | Dud. No obvious problems.
|
| Oct 21 1993 10:24:55:560AM | 931020002 | Steve Golovato | Raised fill to 1.4e-5. Pretty shot, no disruption, 850ka, ran to 1.3s.
|
| Oct 21 1993 09:45:39:090AM | 931020003 | Steve Golovato | Another beauty. Raising rf power each shot. Peak about 200kw this shot.
|
| Oct 21 1993 10:25:22:850AM | 931020003 | Steve Golovato | Another beauty. Raising rf power each shot. Peak about 200kw this shot.
|
| Oct 21 1993 09:52:51:770AM | 931020004 | Steve Golovato | Good shot. Peak rf 300kw.
|
| Oct 21 1993 09:53:17:520AM | 931020005 | Steve Golovato | 5 - Adding H2 puff, 50ms, 40v at 400ms (with quick initial peak at 60v).
UFO blew off of antenna, came from upper right tile, could be from a probe mounted behind tile at this location. Otherwise good looking shot, until disruption at 750ms, rf near 400kw. |
| Oct 21 1993 09:53:52:310AM | 931020006 | Steve Golovato | 6 - Repeat. Moving TF inversion from 1s to 0.8s to speed recool. TF is
the slowest to recool, determines the shot cycle. Good clean shot now that we've removed an imperfection from the antenna. |
| Oct 21 1993 09:54:38:970AM | 931020007 | Steve Golovato | Tweaked pulsed D2 raising slightly between 100-300ms, nl flattening
more and more each shot just before OH zero crossing, where it always jumps up and continues ramping until 1s. 700kw peak rf power. |
| Oct 21 1993 09:55:35:600AM | 931020008 | Steve Golovato | Extended H2 puff to 100ms. Another good shot, peak power about 600kw,
280kw pedestal for 500ms. |
| Oct 21 1993 09:56:02:960AM | 931020009 | Steve Golovato | Enabled Ar puff. Increased H2 puff to 60v from 400-500ms. CX still
doesn't see H signal. Disrupted a little early, at 1.1s. |
| Oct 21 1993 09:56:43:850AM | 931020010 | Steve Golovato | H2 puff was at the wrong voltage, never really puffed. Now hav
100v from 400-420ms (Goetz reminded me that the last time we ran, we could just see a 15ms, 100v puff). Good but disrupted at 870ms. Problems brewing, density ramping up fast at beginning, then falling back at 200ms, then rising again to end of shot, used to be montonic. Also, current is falling off, not reaching programmed value and falling once rf power is above 400kw, eventually disrupting early. No changes made yet but we may have to deal with this soon. |
| Oct 21 1993 09:57:10:910AM | 931020011 | Steve Golovato | Increased H2 puff to 40ms. Disrupted very early. Density ramped
fast to 1e20, current didn't ramp normally, was only around 450ka disrupted at 280ms. Shot looked bad from start. Zmeter digitizer did not init, lost data for several spectroscopy diagnostics. |
| Oct 21 1993 10:04:22:620AM | 931020012 | Steve Golovato | Fill to 1.3e-5, some trivial tweaks to D2 puff. Disrupted at 880ms.
|
| Oct 21 1993 10:06:36:330AM | 931020013 | Steve Golovato | H2 puff 400-700ms at 30v with 100v turnon pulse. CX sees H2 but
mainly during puff. Looked the same, disrupted at 880ms. |
| Oct 21 1993 10:07:08:410AM | 931020014 | Steve Golovato | Disrupted at 550ms. rf hit 1MW for about 2ms.
|
| Oct 21 1993 10:07:39:020AM | 931020015 | Steve Golovato | Raised H2 puff to 35v. Disrupted at 850ms. 480ms, 500-600kw rf pulse.
|
| Oct 21 1993 10:08:28:300AM | 931020016 | Steve Golovato | Raised H2 puff to 35v. Disrupted at 850ms. 480ms, 500-600kw rf pulse. Raised H2 puff to 40v. This may be too much. We'll turn it off for
for a few shots and see how the levels decay. Disrupted early at 380ms. rf came on hard at 330ms, current stopped ramping. |
| Oct 21 1993 10:08:59:320AM | 931020017 | Steve Golovato | Ran longer, disrupted at 830ms. 500-600ms for 0.5s.
|
| Oct 21 1993 10:09:29:670AM | 931020018 | Steve Golovato | Turned off H2 for a few shots to see effect on CX signals.
Fill to 1.4e-5. Trying to reduce knee in current rise at 80ms. Disrupted at 700ms. OH1 not following demand near end just before disruption, getting to negative current limit of 16ka. Current ramp better with higher fill. |
| Oct 21 1993 10:09:59:340AM | 931020019 | Steve Golovato | 19 - Lowered early puff from 40v to 38v to reduce fast early density
ramp. Early disruption, 350ms. Move rf start later to let current reach flattop. |
| Oct 21 1993 10:10:26:530AM | 931020020 | Steve Golovato | Limiter moved back 1cm to 93cm, rf start 50ms later, early gas increased
but not all the way to previous setting. Better shot, disrupted at 800ms. |
| Oct 21 1993 10:10:46:590AM | 931020021 | Steve Golovato | Increased OH1 limits to -18ka/+21ka from -16ka/+20ka. Disrupted
very early, 200ms. |
| Oct 21 1993 10:11:16:120AM | 931020022 | Steve Golovato | Lowered fill to 1.3e-5, fiddled with early puff, but no important
change. Another early disruption at 270ms, during OH1 crossover. |
| Oct 21 1993 10:11:41:600AM | 931020023 | Steve Golovato | Lower fill to 1.2e-5. Also lower early gas. Better, longer, but
dirupted right after rf came on, at 425ms. |
| Oct 21 1993 10:12:38:220AM | 931020024 | Steve Golovato | Moved antenna out to 95cm from 94cm, lowered power. Also tweaked
early gas up. Better shot, disrupted at 940ms, after rf pulse. |
| Oct 21 1993 10:13:02:930AM | 931020025 | Steve Golovato | Raised rf power. Disrupted at 940ms again, may be OH1 current limit
again. Remember negative is positive and vice versa. Seeing evidence of heating of D on CX and neutron data!!!!! |
| Oct 21 1993 10:13:23:180AM | 931020026 | Steve Golovato | Raised OH1 limit to -20ka from -18ka. Disrupted at 960ms.
|
| Oct 21 1993 10:22:26:130AM | 931020027 | Steve Golovato | Dropped off puff after 500ms to 0 at 800ms, bringing down density
both to get scan and increase CX flux. Also supposedly small divertor He puff at 500ms should show up at about 700ms. Transmitter FPA grid bypass capacitor shorted. Requires removal of cavity to repair. RF run is over. This is a no rf shot, plasma ran out to 1.3s. |
| Oct 21 1993 10:23:03:270AM | 931020028 | Steve Golovato | Baseline shot for diamagnetic loop. No fill, no plasma, TF only.
|
| Engineering Operator Comments | ||||
| Shot | Time | Type | Status | Comment |
| 1 | 08:54:42:570AM | Plasma | Ok | No faults. |
| 2 | 09:12:36:280AM | Plasma | Ok | Plasma shot O.K. |
| 3 | 09:28:29:030AM | Plasma | Ok | Plasma shot No faults |
| 4 | 09:45:21:480AM | Plasma | Ok | Plasma shot O.K. |
| 5 | 10:02:56:390AM | Plasma | Ok | Plasma shot ok |
| 6 | 10:22:55:120AM | Plasma | Ok | Plasma shot O.K. |
| 7 | 10:42:30:700AM | Plasma | Ok | Plasma shot O.K. |
| 8 | 11:01:24:030AM | Plasma | Ok | Plasma shot O.K. |
| 9 | 11:19:18:480AM | Plasma | Ok | Plasma shot O.K. |
| 10 | 11:39:57:890AM | Plasma | Ok | no faults |
| 11 | 12:02:38:650PM | Plasma | Ok | no faults |
| 12 | 12:28:26:620PM | Plasma | Ok | no faults |
| 13 | 12:45:44:800PM | Plasma | Ok | Plasma shot O.K. |
| 14 | 12:59:25:070PM | Plasma | Ok | Plasma shot O.K. |
| 15 | 01:12:57:700PM | Plasma | Ok | no faults |
| 16 | 01:27:36:170PM | Plasma | Ok | Plasma shot O.K. |
| 17 | 01:41:13:050PM | Plasma | Ok | Plasma shot. O.K. |
| 18 | 02:01:47:500PM | Plasma | Ok | Plasma shot O.K. |
| 19 | 02:20:49:240PM | Plasma | Ok | Plasma shot O.K. |
| 20 | 02:35:01:400PM | Plasma | Ok | Plasma shot O.K. |
| 21 | 02:51:05:370PM | Plasma | Ok | Plasma shot O.K. |
| 22 | 03:06:22:440PM | Plasma | Ok | Plasma shot O.K. |
| 23 | 03:23:19:630PM | Plasma | Ok | Plasma shot O.K. |
| 24 | 03:39:28:250PM | Plasma | Ok | Plasma shot no faults. |
| 25 | 03:57:41:820PM | Plasma | Ok | Plasma shot No faults. |
| 26 | 04:15:55:290PM | Plasma | Ok | no faults |
| 27 | 04:52:01:710PM | Plasma | Ok | no faults |
| 28 | 05:07:46:760PM | Test | Ok | TF base line shot |