| Miniproposals | ||||||||||
|
| Operators | |
| Session leader(s): | Ron Parker |
| Physics operator(s): | Ian Hutchinson |
| Engineering operator(s): | Gary Dekow |
| Engineering Operator Run Comment |
| MP#307 High bootstrap regimes; SL: Parker; PO:Hutch; EO: Dekow/Fitz |
| Session Leader Plans |
| Physics Operators Plans |
| Session Leader Summaries |
| Entered: Jul 7 2004 03:49:31:803PM |
| Author: To Be Determined |
| The idea of the run was to produce density barriers at low currents in order to maximize the bootstrap current fraction. Unfortuately the run was plagued by both discharge initiation problems and high radiation levels in the discharge. Thus, when barriers were produced the radiation became centrally peaked and strongly cooled the core of the discharge. As the current was lowered, the density at which the temperature collapse occured was reduced; therefore, there was likely no gain in bootstrap fraction at lower currents (lower than the standard 800 kA), although this needs to be confirmed by TRANSP runs. It appears that central heating is needed to sustain the barrier modes at high density. The mini-proposal envisioned having two-frequency ICRF available, but this was not the case for this run as all transmitters were essentially operating at the same frequency. An interesting postcript is that in a subsequent run after boronization the radiated power was lower than on this run and the quality of the ITB's was improved. Thus, while this run was unsuccessful in establishing good density ITB's, we have found that boronization is useful, at least in delaying the core collapse. One can conjecture that boronization coupled with some centrally deposited power would be effective. Trying this approach at higher field, e.g., ~7 T with He3, would be interesting even with all transmitters operating at 80 MHz since the central Ohmic heating would be increased significcantly relative to that at 4.6 T. |
| Physics Operator Summaries |
| Entered: Jul 7 2004 04:37:16:770PM |
| Author: To Be Determined |
| Physop 1021101 PO Hutch SL Parker MP 307 High Bootstrap Fraction ITBs Summary _______ Today was a bad physop day. Starting from a 4.5T initiation we ran into duds. Therefore we loaded a 5.3T initiation from the shot we started at 1021010. This also gave duds. An attempt to adjust it led to a totally silly field evolution, apparently because the shots from that day (and others) are subtly corrupted, but this problem only shows up when you try to change them. Then we loaded shot 20 from yesterday, which had had very reliable startup. This also ran into duds. Tweaks of fields, gas, and ECDC led to a fizzle state. Eventually the shot was reloaded again and then ran reliably until the final shot, 31 which was, appropriately for the day, a fizzle. Radiation was very severe in the off-axis modes we were pursuing. It was reportedly Mo. In most plasmas during H-mode, radiation rose quite rapidly to equal the injected heating power and then self regulate at that level. A new phenomenon was observed mostly at high ICRF power off-axis. After an ITB forms and collapses, the central Te drops to a very low value, e.g. 300eV. These plasmas have hollow Te and very low stored energy. The sawteeth disappear. This appears to be a radiative collapse of the plasma core, reminiscent of the PLT tungsten limiter plasmas. Practically no progress was made on the proposal. But it is pretty clear that we are not going to access high-beta through these conditions without some drastic improvements. Scorecard _________ Shot,Duration(s),Ipmax(MA) Shot,Duration(s),Ipmax 1 1.331 0.831 2 1.940 0.815 3 0.000 0.025 4 1.953 0.793 5 1.951 0.794 6 0.000 0.019 7 0.000 0.019 8 1.956 0.796 9 0.000 0.027 10 1.618 0.796 11 1.954 0.716 12 0.000 0.053 13 0.000 0.050 14 0.000 0.030 15 1.956 0.723 16 0.000 0.027 17 1.953 0.721 18 0.000 0.028 19 0.000 0.030 20 0.000 0.031 21 0.000 0.031 22 0.000 0.031 23 1.957 0.795 24 1.957 0.776 25 1.956 0.774 26 1.954 0.776 27 1.953 0.777 28 1.952 0.767 29 1.951 0.777 30 1.938 0.890 31 0.000 0.032 Finished summary for 1021101 Total of 31 shots. 31 shots. 18 plasmas. 7 fizzles. 6 duds. Details _______ 1021101xxx hutch PHYSICS_OPERATOR Nov 1 2002 8:03:41:443AM . . . . . . . . . . . . . . . . . . . . MP 307 High Bootstrap Fraction Regimes. SL Parker PO Hutch Load from 1021022013 the lower field initiation of Marmar. ---------------------------------------------------------------------------- 1021101xxx hutch PHYSICS_OPERATOR Nov 1 2002 9:07:52:016AM . . . . . . . . . . . . . . . . . . . . Segment 3 preparation. Load from 1020820024 an early EF1 crowbar shaping shot. Copy segment 2 TF to segment 3. Actually, offsets on current may be different on this earlier shot. Probably better just to copy the EF1 programming across. ---------------------------------------------------------------------------- 1021101001 hutch PHYSICS_OPERATOR Nov 1 2002 9:30:05:403AM . . . . . . . . . . . . . . . . . . . . Plasma. Got about 2MW but H-mode is elm-free. Disrupts at 1.3s. Big thrash in startup. Some hard x-rays. Problem with hybrid camac. Increase nl04 to 1e20. ---------------------------------------------------------------------------- 1021101002 hutch PHYSICS_OPERATOR Nov 1 2002 9:48:27:156AM . . . . . . . . . . . . . . . . . . . . Argon to 20ms from 40ms before this shot. Plasma. Not an ITB Load from 1021010005 segment 2. That's nl04 of .85 and slightly different shape. ---------------------------------------------------------------------------- 1021101002 hutch PHYSICS_OPERATOR Nov 1 2002 9:56:58:710AM . . . . . . . . . . . . . . . . . . . . Reboot all linux boxes for mds. ---------------------------------------------------------------------------- 1021101003 hutch PHYSICS_OPERATOR Nov 1 2002 10:16:16:606AM . . . . . . . . . . . . . . . . . . . . Dud. Raise gas to 29ms. ---------------------------------------------------------------------------- 1021101004 hutch PHYSICS_OPERATOR Nov 1 2002 10:26:56:586AM . . . . . . . . . . . . . . . . . . . . Plasma. Signs of ITB at the end of the H-modes but radiation is sufficiently high that we don't get very far. Argon dropped to 30ms from 40ms. ---------------------------------------------------------------------------- 1021101005 hutch PHYSICS_OPERATOR Nov 1 2002 10:42:08:253AM . . . . . . . . . . . . . . . . . . . . Plasma. TF current to 123 from 124kA. Argon to 1ms (basically off). RXU to -.025 from -.02 ---------------------------------------------------------------------------- 1021101006 hutch PHYSICS_OPERATOR Nov 1 2002 10:52:38:343AM . . . . . . . . . . . . . . . . . . . . ICEF4 to 1310 from -1315 before this shot. Dud. Br offset to .0025 from .002 ---------------------------------------------------------------------------- 1021101007 hutch PHYSICS_OPERATOR Nov 1 2002 11:10:40:346AM . . . . . . . . . . . . . . . . . . . . Dud undo the field tweaks. raise fill puff to 31ms. ---------------------------------------------------------------------------- 1021101008 hutch PHYSICS_OPERATOR Nov 1 2002 11:29:02:363AM . . . . . . . . . . . . . . . . . . . . Plasma. ---------------------------------------------------------------------------- 1021101009 hutch PHYSICS_OPERATOR Nov 1 2002 11:37:18:700AM . . . . . . . . . . . . . . . . . . . . Dud Give up on this startup. Load the entire shot 1021010005. Turn off argon. ---------------------------------------------------------------------------- 1021101010 hutch PHYSICS_OPERATOR Nov 1 2002 11:58:08:286AM . . . . . . . . . . . . . . . . . . . . Plasma. Some density peaking. Lower Ip to .7MA. ---------------------------------------------------------------------------- 1021101011 hutch PHYSICS_OPERATOR Nov 1 2002 12:14:32:410PM . . . . . . . . . . . . . . . . . . . . Plasma. Still very radiative. Move plasma in 3mm. RCUR to .68 at 1ms. ---------------------------------------------------------------------------- 1021101012 hutch PHYSICS_OPERATOR Nov 1 2002 12:27:44:850PM . . . . . . . . . . . . . . . . . . . . Fizzle. There is something strange about what happened to the rcur predictor in segment 1. It came up with a message saying that all the predictor weights are zero and then it called the predictor. That should not have happened. This shot behaves as if there really is no feedback. There does not seem to be a controller algorithm in this place. Put one in and called it. Looks sort of sensible. Load and hope. This is an interesting breakdown in which the plasma current seems to reach 30kA even though Bz is negative and never swings positive. ---------------------------------------------------------------------------- 1021101013 hutch PHYSICS_OPERATOR Nov 1 2002 12:43:02:593PM . . . . . . . . . . . . . . . . . . . . Fizzle. Same as last one. These are really broken. There is no field ramp. Interesting blips as the field goes slightly positive. Bring the 1ms point way down, to .63m. ---------------------------------------------------------------------------- 1021101014 hutch PHYSICS_OPERATOR Nov 1 2002 12:56:30:286PM . . . . . . . . . . . . . . . . . . . . Dud. No TF. Load segment 1 from 1021031020 ---------------------------------------------------------------------------- 1021101015 hutch PHYSICS_OPERATOR Nov 1 2002 1:14:28:646PM . . . . . . . . . . . . . . . . . . . . Plasma. Wolfe informs me that days 1008 to 1016 have some subtle corruption in segment 1 that was caused by hitting the algs button. Now we have loaded an OK shot. This is a hollow Te shot with ghastly radiation. Move rcur out again by 2mm. ---------------------------------------------------------------------------- 1021101016 hutch PHYSICS_OPERATOR Nov 1 2002 1:28:03:966PM . . . . . . . . . . . . . . . . . . . . Dud. No obvious reason. No changes. ---------------------------------------------------------------------------- 1021101017 hutch PHYSICS_OPERATOR Nov 1 2002 1:46:24:140PM . . . . . . . . . . . . . . . . . . . . Plasma. Cold cores again. Install a current ramp from 800 to 600kA. ---------------------------------------------------------------------------- 1021101018 hutch PHYSICS_OPERATOR Nov 1 2002 2:16:06:266PM . . . . . . . . . . . . . . . . . . . . Dud. Do 5 minutes ECDC to see if we can break this dud problem. Fill puff to 30ms from 35ms. ---------------------------------------------------------------------------- 1021101019 hutch PHYSICS_OPERATOR Nov 1 2002 2:22:26:656PM . . . . . . . . . . . . . . . . . . . . Fizzle. At least it is not a dud! ---------------------------------------------------------------------------- 1021101020 hutch PHYSICS_OPERATOR Nov 1 2002 2:29:22:630PM . . . . . . . . . . . . . . . . . . . . Fizzle. Fill puff back to 35ms. Br offset to 1.5mT ---------------------------------------------------------------------------- 1021101021 hutch PHYSICS_OPERATOR Nov 1 2002 2:47:06:770PM . . . . . . . . . . . . . . . . . . . . Fizzle Br offset to 1.8mT Rcur point at 1ms to .67m from .66m. ---------------------------------------------------------------------------- 1021101022 hutch PHYSICS_OPERATOR Nov 1 2002 3:13:55:140PM . . . . . . . . . . . . . . . . . . . . Fizzle. Load segment 1 from 1021031020 in desperation. I think there is something here I don't understand. ---------------------------------------------------------------------------- 1021101023 hutch PHYSICS_OPERATOR Nov 1 2002 3:26:57:926PM . . . . . . . . . . . . . . . . . . . . Plasma. This is a truly hollow 300eV central Te. Load segment 2 from 1021010007. ---------------------------------------------------------------------------- 1021101024 hutch PHYSICS_OPERATOR Nov 1 2002 3:36:04:530PM . . . . . . . . . . . . . . . . . . . . Plasma. TF to 130kA (4.7T). ---------------------------------------------------------------------------- 1021101025 hutch PHYSICS_OPERATOR Nov 1 2002 3:49:49:596PM . . . . . . . . . . . . . . . . . . . . Plasma. No central cooling. TF to 127kA. 4.6T. ---------------------------------------------------------------------------- 1021101026 hutch PHYSICS_OPERATOR Nov 1 2002 4:22:20:590PM . . . . . . . . . . . . . . . . . . . . Plasma. TF to 124kA. ---------------------------------------------------------------------------- 1021101027 hutch PHYSICS_OPERATOR Nov 1 2002 4:22:42:293PM . . . . . . . . . . . . . . . . . . . . Plasma No PCS changes. Lower power for next shot. ---------------------------------------------------------------------------- 1021101028 hutch PHYSICS_OPERATOR Nov 1 2002 4:34:55:560PM . . . . . . . . . . . . . . . . . . . . Plasma. With 1.7MW the hollow temperature recovers. ---------------------------------------------------------------------------- 1021101029 hutch PHYSICS_OPERATOR Nov 1 2002 4:44:15:460PM . . . . . . . . . . . . . . . . . . . . Plasma. 1.4MW does not recover. Ip to 0.9MA. ---------------------------------------------------------------------------- 1021101030 hutch PHYSICS_OPERATOR Nov 1 2002 5:00:40:120PM . . . . . . . . . . . . . . . . . . . . Plasma. Raise Bt to 150kA. ---------------------------------------------------------------------------- 1021101031 hutch PHYSICS_OPERATOR Nov 1 2002 5:00:50:700PM . . . . . . . . . . . . . . . . . . . . Fizzle. |
| Session Leader Comments |
| Physics Operator Comments | |||
| Nov 1 2002 08:03:41:443AM | Ian Hutchinson | MP 307 High Bootstrap Fraction Regimes. SL Parker PO Hutch Load from 1021022013 the lower field initiation of Marmar. | |
| Nov 1 2002 09:07:52:017AM | Ian Hutchinson | Segment 3 preparation. Load from 1020820024 an early EF1 crowbar shaping shot. Copy segment 2 TF to segment 3. Actually, offsets on current may be different on this earlier shot. Probably better just to copy the EF1 programming across. | |
| Nov 1 2002 09:30:05:403AM | 1021101001 | Ian Hutchinson | Plasma. Got about 2MW but H-mode is elm-free. Disrupts at 1.3s. Big thrash in startup. Some hard x-rays. Problem with hybrid camac. Increase nl04 to 1e20. |
| Nov 1 2002 09:48:27:157AM | 1021101002 | Ian Hutchinson | Argon to 20ms from 40ms before this shot. Plasma. Not an ITB Load from 1021010005 segment 2. That's nl04 of .85 and slightly different shape. |
| Nov 1 2002 09:56:58:710AM | 1021101002 | Ian Hutchinson | Reboot all linux boxes for mds. |
| Nov 1 2002 10:16:16:607AM | 1021101003 | Ian Hutchinson | Dud. Raise gas to 29ms. |
| Nov 1 2002 10:26:56:587AM | 1021101004 | Ian Hutchinson | Plasma. Signs of ITB at the end of the H-modes but radiation is sufficiently high that we don't get very far. Argon dropped to 30ms from 40ms. |
| Nov 1 2002 10:42:08:253AM | 1021101005 | Ian Hutchinson | Plasma. TF current to 123 from 124kA. Argon to 1ms (basically off). RXU to -.025 from -.02 |
| Nov 1 2002 10:52:38:343AM | 1021101006 | Ian Hutchinson | ICEF4 to 1310 from -1315 before this shot. Dud. Br offset to .0025 from .002 |
| Nov 1 2002 11:10:40:347AM | 1021101007 | Ian Hutchinson | Dud undo the field tweaks. raise fill puff to 31ms. |
| Nov 1 2002 11:29:02:363AM | 1021101008 | Ian Hutchinson | Plasma. |
| Nov 1 2002 11:37:18:700AM | 1021101009 | Ian Hutchinson | Dud Give up on this startup. Load the entire shot 1021010005. Turn off argon. |
| Nov 1 2002 11:58:08:287AM | 1021101010 | Ian Hutchinson | Plasma. Some density peaking. Lower Ip to .7MA. |
| Nov 1 2002 12:14:32:410PM | 1021101011 | Ian Hutchinson | Plasma. Still very radiative. Move plasma in 3mm. RCUR to .68 at 1ms. |
| Nov 1 2002 12:27:44:850PM | 1021101012 | Ian Hutchinson | Fizzle. There is something strange about what happened to the rcur predictor in segment 1. It came up with a message saying that all the predictor weights are zero and then it called the predictor. That should not have happened. This shot behaves as if there really is no feedback. There does not seem to be a controller algorithm in this place. Put one in and called it. Looks sort of sensible. Load and hope. This is an interesting breakdown in which the plasma current seems to reach 30kA even though Bz is negative and never swings positive. |
| Nov 1 2002 12:43:02:593PM | 1021101013 | Ian Hutchinson | Fizzle. Same as last one. These are really broken. There is no field ramp. Interesting blips as the field goes slightly positive. Bring the 1ms point way down, to .63m. |
| Nov 1 2002 12:56:30:287PM | 1021101014 | Ian Hutchinson | Dud. No TF. Load segment 1 from 1021031020 |
| Nov 1 2002 01:14:28:647PM | 1021101015 | Ian Hutchinson | Plasma. Wolfe informs me that days 1008 to 1016 have some subtle corruption in segment 1 that was caused by hitting the algs button. Now we have loaded an OK shot. This is a hollow Te shot with ghastly radiation. Move rcur out again by 2mm. |
| Nov 1 2002 01:28:03:967PM | 1021101016 | Ian Hutchinson | Dud. No obvious reason. No changes. |
| Nov 1 2002 01:46:24:140PM | 1021101017 | Ian Hutchinson | Plasma. Cold cores again. Install a current ramp from 800 to 600kA. |
| Nov 1 2002 02:16:06:267PM | 1021101018 | Ian Hutchinson | Dud. Do 5 minutes ECDC to see if we can break this dud problem. Fill puff to 30ms from 35ms. |
| Nov 1 2002 02:22:26:657PM | 1021101019 | Ian Hutchinson | Fizzle. At least it is not a dud! |
| Nov 1 2002 02:29:22:630PM | 1021101020 | Ian Hutchinson | Fizzle. Fill puff back to 35ms. Br offset to 1.5mT |
| Nov 1 2002 02:47:06:770PM | 1021101021 | Ian Hutchinson | Fizzle Br offset to 1.8mT Rcur point at 1ms to .67m from .66m. |
| Nov 1 2002 03:13:55:140PM | 1021101022 | Ian Hutchinson | Fizzle. Load segment 1 from 1021031020 in desperation. I think there is something here I don't understand. |
| Nov 1 2002 03:26:57:927PM | 1021101023 | Ian Hutchinson | Plasma. This is a truly hollow 300eV central Te. Load segment 2 from 1021010007. |
| Nov 1 2002 03:36:04:530PM | 1021101024 | Ian Hutchinson | Plasma. TF to 130kA (4.7T). |
| Nov 1 2002 03:49:49:597PM | 1021101025 | Ian Hutchinson | Plasma. No central cooling. TF to 127kA. 4.6T. |
| Nov 1 2002 04:22:20:590PM | 1021101026 | Ian Hutchinson | Plasma. TF to 124kA. |
| Nov 1 2002 04:22:42:293PM | 1021101027 | Ian Hutchinson | Plasma No PCS changes. Lower power for next shot. |
| Nov 1 2002 04:34:55:560PM | 1021101028 | Ian Hutchinson | Plasma. With 1.7MW the hollow temperature recovers. |
| Nov 1 2002 04:44:15:460PM | 1021101029 | Ian Hutchinson | Plasma. 1.4MW does not recover. Ip to 0.9MA. |
| Nov 1 2002 05:00:40:120PM | 1021101030 | Ian Hutchinson | Plasma. Raise Bt to 150kA. |
| Nov 1 2002 05:00:50:700PM | 1021101031 | Ian Hutchinson | Fizzle. |
| Engineering Operator Comments | ||||
| Shot | Time | Type | Status | Comment |
| 1 | 09:00:53:810AM | Plasma | Ok | |
| 2 | 09:31:51:080AM | Plasma | Ok | |
| 3 | 09:59:04:230AM | Plasma | Ok | |
| 4 | 10:14:14:663AM | Plasma | Ok | |
| 5 | 10:27:24:560AM | Plasma | Ok | |
| 6 | 10:47:49:770AM | Plasma | Ok | |
| 7 | 11:01:02:070AM | Plasma | Ok | |
| 8 | 11:14:15:793AM | Plasma | Ok | |
| 9 | 11:27:19:030AM | Plasma | Ok | |
| 10 | 11:41:21:333AM | Plasma | Ok | |
| 11 | 11:54:46:777AM | Plasma | Ok | |
| 12 | 12:13:00:467PM | Plasma | Ok | |
| 13 | 12:27:10:300PM | Plasma | Ok | |
| 14 | 12:40:32:633PM | Plasma | Ok | |
| 15 | 12:53:29:497PM | Plasma | Ok | |
| 16 | 01:12:35:800PM | Plasma | Ok | |
| 17 | 01:25:42:757PM | Plasma | Ok | |
| 18 | 01:43:53:850PM | Plasma | Ok | |
| 19 | 02:04:50:533PM | Plasma | Ok | |
| 20 | 02:23:00:283PM | Plasma | Ok | |
| 21 | 02:37:16:073PM | Plasma | Ok | |
| 22 | 02:50:12:577PM | Plasma | Ok | |
| 23 | 03:03:16:783PM | Plasma | Ok | |
| 24 | 03:20:29:347PM | Plasma | Ok | |
| 25 | 03:33:43:600PM | Plasma | Ok | |
| 26 | 03:47:58:543PM | Plasma | Ok | |
| 27 | 04:02:38:490PM | Plasma | Ok | |
| 28 | 04:17:06:623PM | Plasma | Ok | |
| 29 | 04:30:18:750PM | Plasma | Ok | |
| 30 | 04:43:33:927PM | Plasma | Ok | |
| 31 | 04:57:52:880PM | Plasma | Ok | |