| Miniproposals | ||||||||||
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| Operators | |
| Session leader(s): | Ken Gentle |
| Physics operator(s): | Earl Marmar |
| Engineering operator(s): | Frank Silva,Bill Cochran,Vinny Bertolino |
| Engineering Operator Run Comment |
| MP186/Marmer |
| Session Leader Plans |
| Physics Operators Plans |
| Session Leader Summaries |
| Entered: Jul 7 2004 03:49:17:757PM |
| Author: To Be Determined |
| MP186 Cold pulse experiments. SL: Ken Gentle PO: Marmar EO: Silva, Cochrane, Bertolino The objective was to produce temperature perturbations by the laser ablation injection of impurities suitable for analysis of thermal transport. The specific goal was to find discharges similar to those in TEXT and TFTR in which edge cooling induced core temperature rises. These were circular limited ohmic discharges, generally at low density. These core temperature rises are particularly difficult to explain and offer a unique set of conditions for testing transport theories. The run plan was to set up circular, inside limited discharges at 5.4 T (for good ECE coverage) at 0.5 MA and as low a density as reasonable. Various impurities -- carbon, scandium, niobium, etc. -- were tested for their ability to induce suitable increases in radiation and edge temperature. If core temperature rises were found, scans in density and shape would be made to determine the range over which the effect would appear. Suitable target discharges at line-average density of 0.6 were obtained. After optimizing the injector, niobium injections were capable of generating great increases in radiation power (several times the plateau level) and good edge temperature perturbations (>50%). These caused cooling at all radii, possibly because niobium penetrates quickly and radiates strongly at all radii. Neither carbon nor scandium injections were capable of inducing strong perturbations; the radiation level was not as much as doubled, and no significant decrease in edge temperature could be found.. To search for the effect under conditions as close to those in which it had been found in TEXT, the current was lowered to 0.3 MA. Neither carbon nor scandium produced significant perturbations, but both iron and niobium did. Core temperature increases were not found under any conditions. Comparison of the injections on these circular, limited discharges with standard 1 MA diverted reference shots on this run and niobium injection from run 971210 suggests that injection efficiency is equivalent for the two configurations. The niobium and iron injections are suitable for electron thermal transport analysis, but the analysis will be complicated by the need to include impurity transport for the space-time profiles of radiation losses. SHOT LIST Shot 004 First attempt at small, limited plasma Shot 005. C injection at 0.7 s shot 006 carbon injection at 0.7 sec. Barely perceptible on 2-pi bolometer, not on edge Te. Shot 007 carbon injection at 0.7 sec not detectable Shot 008 Moly injection at 0.7 see, but 2-PT radiation only increased 35%; no effect on edge Te. Shot 011 Nb injection at 0.7 sec, but only 30% increase in 2-PI radiation; no effect on edge Te. Shot 012 Nb injection at 0.8 sec. Radiated power doubled, but effect on edge Te very small. Shot 013 Return to reference conditions (I MA diverted) Nb injection at 0.8 sec. Radiated power doubled, but effect on edge Te very small. Shot 018 Circular, inside-limited discharge Nb injection at 0.8 sec, but radiated power increased only 60%. No Te effects. Shot 019 Circular, inside-limited discharge. Nb injection at 0.8 sec, Shot 020 Circular, inside-limited discharge. Nb injection at 0.8 sec, Shot 021 Corrected problem with injector. Nb injection at 0.8 sec; increased radiated power by factor of 5. Good edge temperature perturbation, but Te falls everywhere. Shot 023 Nb injection at 0.8 s: increased radiated power (2-PI) from 100 kw to 400 kW (cf. ohmic power ~500 kW) Strong temperature decreases at all radii. Shot 024 C injection at 0.8 sec; Radiated power doubled, but little effect on Te. Shot 025 C injection at 0.8 sec Weaker effect Shot 026 Sc injection at 0.8 see; Weak effect Shot 027 Sc injection at 0.8 sec. Radiated power doubled but no Te effect Shot 031 Sc injection at 0.8 sec. No Te effect Natural injection at 0.62 -- Te drop appears diffusive Shot 037 Fe injection at 0.8 sec. Significant, but slow edge temperature decreases. Shot 038 Nb injection at 0.8. Strong temperature decreases at all radii. Shot 039 Nb injection at 0.8. Strong temperature decreases at all radii. Shot 040. Nb injection at 0.85 to inject at lower ne Shot 041 Nb injection at 0.85. Strong temperature decreases at all radii. Shot 042 Nb injection at 0.8 s |
| Physics Operator Summaries |
| Entered: Jul 7 2004 04:36:58:520PM |
| Author: To Be Determined |
| MP186 Cold pulse experiments. SL: Ken Gentle PO: Marmar EO: Silva, Cochrane, Bertolino Standard ECDC in deuterium for a couple of hours before run. Engineering setup as on 980107031, with TF under hybrid control Gas setup - fill K-side with 30 PSI of D2, hybrid enable fill B-top with 6 PSI of D2, hybrid enable fill B-side-lower with 1 PSI of Ar, hybrid enable J-bottom should be pumped out and hybrid disabled. Start by running a 1 MA shot like 980107031, but with no nitrogen. Then load segment 2 from modified 950606012, inner wall limited, 0.5 MA, near circular discharge. coldstart hybrid; no errors The machine ran well today, and we got the shape (circular, inner wall limited), currents and densities that were desired. On the main MP, injections were made with carbon, scandium, iron, and niobium. No non-local effects were observed. We also got some high power RF, circular, L-mode piggy-backing on many shots. Shot 28 had a Li pellet into an ohmic phase. 42 attempts, 35 plasmas, 7 fizzles. 1) settings from 980107033, no nitrogen, lpi barrel 4 at 0.7 seconds; fizzle, B_r looks a little too negative 2) no changes; no LPI; plasma; rather high density 3) repeat; plasma; better density 4) turn off segment 2; turn on segment 3; 0.5 MA circular, limited plasma; fizzle; got to 50 kA 5) no changes; plasma; .5 MA, kappa=1.05 6) no changes; plasma; nl_04 ~ 4e19; hard burst at 115 ms 7) nl_04 program to 4e19; plasma; a bit of a thrash at .1 sec, with a hards burst 8) nl_04 prog to 3e19; program current to go up to .6 MA and then down to .5 MA; plasma; still thrashing a bit early. 9) tweak the segment 1 gas programming (down); plasma; early hards; disrupt at 0.3 sec; 10) undo early gas tweak; plasma; still disrupt at 0.3; 11) reload segment 1 from 980107031; increase early segment 2 nl_04 and segment 2 gas prog voltage; plasma; no hards; nice shot 12) repeat; plasma 13) turn off seg 3, turn on seg 2; 1 MA diverted; plasma 14) back to shot 12 programming; fizzle; B_R looks slightly positive 15) B_R offset to .0055 from .006; plasma; disrupt at .187; hards early. 16) add 1 msec to prepuff; plasma; disrupt at 0.4; brick? 17) add 1 more msec to prepuff; plasma; disrupt at .3; 18) reload segment 3 from shot 12; plasma; ratty early (no hards); ok after 0.5 s 19) reduce seg 1 gas prog slightly; plasma 20) repeat; plasma; early hards spike 21) repeat; plasma; better impurity injection 22) decrease pulsed gas prog in seg 3; fizzle; 23) repeat; plasma 24) a few rampdown tweaks; plasma 25) repeat; plasma 26) repeat; plasma 27) repeat; plasma 28) LPI fired at 0.9s; plasma; pellet. 29) LPI off; fizzle 30) repeat; plasma 31) extend I_p flattop to 1.2 s, add RF after .9 s; plasma; close to 3 MW RF 32) program for I_p = 400 kA; fizzle 33) B_R offset to .005 from .0055; plasma; got 430 kA 34) program for I_p = 300 kA; plasma; 335 kA at .8 s; 3 MW RF 35) repeat; fizzle 36) B_R offset to .0055 from .005; plasma 37) repeat; plasma 38) repeat; plasma 39) nl_04 program down to 2.0e19; plasma; nl_04 = 3.43 at .8 s 40) lower voltage prog for pulsed gas in both segments 1 and 3; plasma; nl_04 = 3.15 at .85 s 41) program to nl_04 = 4.5e20; increase voltage program on pulsed gas for segs 1 and 3; got 5.6e19 at .85 s; plasma 42) raise nl_04 to 6e19 and raise voltage prog on pulsed gas; plasma; disrupt at .28 s. |
| Session Leader Comments | |||
| Jan 8 1998 09:12:04:730AM | 980108004 | Ken Gentle | First attempt at small, limited plasma |
| Jan 8 1998 09:47:40:790AM | 980108006 | Ken Gentle | Carbon injection at 0.7 sec. Barely perceptible on 2-pi bolometer, not on edge Te. |
| Jan 8 1998 09:52:07:350AM | 980108007 | Ken Gentle | Carbon injection at 0.7 sec not detectable |
| Jan 8 1998 10:07:20:280AM | 980108008 | Ken Gentle | Moly injection at 0.7 sec, but 2-PI radiation only increased 35%; no effect on edge Te. |
| Jan 8 1998 10:39:34:870AM | 980108011 | Ken Gentle | Nb injection at 0.7 sec, but only 30% increase in 2-PI radiation; no effect on edge Te. |
| Jan 8 1998 10:53:10:440AM | 980108012 | Ken Gentle | Nb injection at 0.8 sec. Radiated power doubled, but effect on edge Te very small. |
| Jan 8 1998 11:07:59:410AM | 980108013 | Ken Gentle | Return to refernece conditions (1 MA diverted) Nb injection at 0.8 sec. Radiated power doubled, but effect on edge Te very small. |
| Jan 8 1998 11:52:35:800AM | 980108018 | Ken Gentle | Circular, inside-limited discharge. Nb injection at 0.8 sec, but radiated power increased only 60%. No Te effects. |
| Jan 8 1998 12:43:33:680PM | 980108021 | Ken Gentle | Corrected problem with injector. Nb injection at 0.8 sec; increased radiated power by factor of 5. Good edge temperature perturbation, but Te falls everywhere. |
| Jan 8 1998 12:56:08:060PM | 980108023 | Ken Gentle | Nb injection at 0.8 sec; increased radiated power (2-PI) from 100 kW to 400 kW (cf. ohmic power ~ 500 kW) Strong temperature decreases at all radii. |
| Jan 8 1998 01:14:40:340PM | 980108024 | Ken Gentle | C injection at 0.8 sec; Radiated power doubled, but little effect on Te. |
| Jan 8 1998 01:31:11:230PM | 980108025 | Ken Gentle | C injection at 0.8 sec; Weaker effect |
| Jan 8 1998 01:53:07:720PM | 980108026 | Ken Gentle | Sc injection at 0.8 sec; Weak effect |
| Jan 8 1998 02:05:56:150PM | 980108027 | Ken Gentle | Sc injection at 0.8 sec. Radiated power doubled, but no Te effect |
| Jan 8 1998 02:55:45:950PM | 980108031 | Ken Gentle | Sc injection at 0.8 sec. No Te effect Natural injection at 0.62 -- Te drop appears diffusive |
| Jan 8 1998 04:06:22:790PM | 980108037 | Ken Gentle | Fe injection at 0.8 sec. Significant, but slow edge temperature decreases. |
| Jan 8 1998 04:18:41:530PM | 980108038 | Ken Gentle | Nb injection at 0.8. Strong temperature decreases at all radii. |
| Jan 8 1998 04:51:49:130PM | 980108041 | Ken Gentle | Nb injection at 0.85. Strong temperature decreases at all radii. |
| Physics Operator Comments | |||
| Jan 8 1998 08:20:03:200AM | Earl Marmar | MP186 Cold pulse experiments. Standard ECDC in deuterium for a couple of hours before run. Engineering setup as on 980107031, with TF under hybrid control Gas setup - fill K-side with 30 PSI of D2, hybrid enable fill B-top with 6 PSI of D2, hybrid enable fill B-side-lower with 1 PSI of Ar, hybrid enable J-bottom should be pumped out and hybrid disabled. Start by running a 1 MA shot like 980107031, but with no nitrogen. Then load segment 2 from modified 950606012, inner wall limited, 0.5 MA, near circular discharge. coldstart hybrid; no errors | |
| Jan 8 1998 08:47:45:550AM | 980108001 | Earl Marmar | 1) settings from 980107033, no nitrogen, lpi barrel 4 at 0.7 seconds; fizzle, B_r looks a little too negative |
| Jan 8 1998 08:54:33:930AM | 980108002 | Earl Marmar | repeat with no changes; plasma; marfe'y with high density |
| Jan 8 1998 09:04:19:960AM | 980108003 | Earl Marmar | no changes; plasma; lower density |
| Jan 8 1998 09:13:27:610AM | 980108004 | Earl Marmar | load limited plasma program (now in segment 3); fizzle; got to 50 kA & then hit something |
| Jan 8 1998 09:32:51:700AM | 980108005 | Earl Marmar | no changes; plasma; got the shape and current; density is too high |
| Jan 8 1998 09:38:13:320AM | 980108006 | Earl Marmar | no changes; plasma; nl_04 ~ 4e19; hard burst at 115 ms |
| Jan 8 1998 09:50:49:850AM | 980108007 | Earl Marmar | nl_04 program to 4e19; plasma; a bit of a thrash at .1 sec, with a hards burst. |
| Jan 8 1998 10:03:58:390AM | 980108008 | Earl Marmar | nl_04 prog to 3e19; program current to go up to .6 MA and then down to .5 MA; plasma; still thrashing early; nl_04 ~ 3.5e20 |
| Jan 8 1998 10:15:11:570AM | 980108009 | Earl Marmar | tweak segment 1 gas programming down; plasma; disrupt at .3 s; early hards |
| Jan 8 1998 10:30:43:220AM | 980108010 | Earl Marmar | undo early gas tweak; plasma; still disrupt at .3 s |
| Jan 8 1998 10:33:57:230AM | 980108011 | Earl Marmar | reload segment 1 from 980107031; increase early segment 2 nl_04 and segment 2 gas prog voltage; plasma; nice shot; no hards. |
| Jan 8 1998 10:58:00:740AM | 980108012 | Earl Marmar | repeat; plasma; there is a slight R oscillation which shows up on (mflux) Bz0 & R(m), H-alpha, ECE, etc. |
| Jan 8 1998 11:01:19:080AM | 980108013 | Earl Marmar | turn off seg 3, turn on seg 2; 1 MA diverted; plasma |
| Jan 8 1998 11:11:17:360AM | 980108014 | Earl Marmar | back to programming from shot 12; fizzle; B_R looks a bit positive |
| Jan 8 1998 11:23:09:060AM | 980108015 | Earl Marmar | B_R offset to .0055 from .006; very minor tweak to seg 1 gas prog (earlier by 1 msec); plasma; disrupt at .187; hards early. |
| Jan 8 1998 11:27:44:570AM | 980108016 | Earl Marmar | add 1 msec to prepuff; undo 1 msec shift of seg 1 gas prog; disrupt at .4; brick? |
| Jan 8 1998 11:40:49:940AM | 980108017 | Earl Marmar | add 1 more msec to prepuff; disrupt at .3; still early hards. |
| Jan 8 1998 12:14:31:320PM | 980108018 | Earl Marmar | reload segment 3 from shot 12; plasma; ratty early (no hards); ok after 0.5 s |
| Jan 8 1998 12:14:50:170PM | 980108019 | Earl Marmar | reduce seg 1 gas prog slightly; plasma |
| Jan 8 1998 12:38:06:630PM | 980108020 | Earl Marmar | repeat; plasma |
| Jan 8 1998 12:39:33:140PM | 980108021 | Earl Marmar | repeat; plasma; better impurity injection |
| Jan 8 1998 12:44:39:900PM | 980108022 | Earl Marmar | decrease pulsed gas prog in seg 3; fizzle; 50 kA |
| Jan 8 1998 12:58:51:780PM | 980108023 | Earl Marmar | repeat; plasma |
| Jan 8 1998 01:29:07:560PM | 980108024 | Earl Marmar | a few rampdown tweaks; plasma |
| Jan 8 1998 01:29:21:650PM | 980108025 | Earl Marmar | repeat; plasma |
| Jan 8 1998 02:20:59:410PM | 980108028 | Earl Marmar | LPI fired at 0.9s; plasma; pellet. |
| Jan 8 1998 02:21:15:580PM | 980108029 | Earl Marmar | LPI off; fizzle |
| Jan 8 1998 02:40:18:710PM | 980108030 | Earl Marmar | repeat; plasma |
| Jan 8 1998 03:32:46:260PM | 980108031 | Earl Marmar | extend I_p flattop to 1.2 s, add RF after .9 s; plasma; close to 3 MW RF |
| Jan 8 1998 03:33:01:270PM | 980108032 | Earl Marmar | program for I_p = 400 kA; fizzle |
| Jan 8 1998 03:33:13:600PM | 980108033 | Earl Marmar | B_R offset to .005 from .0055; plasma; got 430 kA |
| Jan 8 1998 03:33:30:160PM | 980108034 | Earl Marmar | program for I_p = 300 kA; plasma; 335 kA at .8 s; 3 MW RF |
| Jan 8 1998 03:33:44:250PM | 980108035 | Earl Marmar | repeat; fizzle |
| Jan 8 1998 05:03:27:200PM | 980108036 | Earl Marmar | B_R offset to .0055 from .005; plasma |
| Jan 8 1998 05:03:43:640PM | 980108037 | Earl Marmar | repeat; plasma |
| Jan 8 1998 05:03:56:010PM | 980108038 | Earl Marmar | repeat; plasma |
| Jan 8 1998 05:04:08:150PM | 980108039 | Earl Marmar | nl_04 program down to 2.0e19; plasma; nl_04 = 3.43 at .8 s |
| Jan 8 1998 05:04:30:270PM | 980108040 | Earl Marmar | lower voltage prog for pulsed gas in both segments 1 and 3; plasma; nl_04 = 3.15 at .85 s |
| Jan 8 1998 05:04:43:070PM | 980108041 | Earl Marmar | program to nl_04 = 4.5e20; increase voltage program on pulsed gas for segs 1 and 3; got 5.6e19 at .85 s; plasma |
| Jan 8 1998 05:04:57:880PM | 980108042 | Earl Marmar | raise nl_04 to 6e19 and raise voltage prog on pulsed gas; plasma; disrupt at .28 s. |
| Engineering Operator Comments | ||||
| Shot | Time | Type | Status | Comment |
| 1 | 08:38:16:120AM | Plasma | Ok | |
| 2 | 08:46:12:730AM | Plasma | Ok | no faults /plasma |
| 3 | 08:58:47:250AM | Plasma | Ok | no faults/plasma |
| 4 | 09:09:08:740AM | Plasma | Ok | no faults/fizzel |
| 5 | 09:17:31:650AM | Plasma | Ok | no faults/plasma |
| 6 | 09:30:32:420AM | Plasma | Ok | no faults/plasma |
| 7 | 09:42:37:260AM | Plasma | Ok | n0o faults/plasma |
| 8 | 09:55:11:150AM | Plasma | Ok | no faults/plasma |
| 9 | 10:08:07:330AM | Plasma | Ok | no faults |
| 10 | 10:17:23:650AM | Plasma | Ok | no faults |
| 11 | 10:27:47:480AM | Plasma | Ok | no faults |
| 12 | 10:39:20:270AM | Plasma | Ok | no faults/plasma |
| 13 | 10:51:43:180AM | Plasma | Ok | |
| 14 | 11:06:26:690AM | Plasma | Ok | |
| 15 | 11:14:05:820AM | Plasma | Ok | |
| 16 | 11:22:38:210AM | Plasma | Ok | |
| 17 | 11:32:26:520AM | Plasma | Ok | |
| 18 | 11:42:23:590AM | Plasma | Ok | |
| 19 | 11:58:15:940AM | Plasma | Ok | |
| 20 | 12:13:42:100PM | Plasma | Ok | |
| 21 | 12:25:46:690PM | Plasma | Ok | |
| 22 | 12:39:23:410PM | Plasma | Ok | |
| 23 | 12:47:54:830PM | Plasma | Ok | |
| 24 | 01:04:51:250PM | Plasma | Ok | |
| 25 | 01:21:40:900PM | Plasma | Ok | |
| 26 | 01:39:51:360PM | Plasma | Ok | |
| 27 | 01:50:28:250PM | Plasma | Ok | |
| 28 | 02:05:47:940PM | Plasma | Ok | |
| 29 | 02:17:10:340PM | Plasma | Ok | |
| 30 | 02:25:55:760PM | Plasma | Ok | |
| 31 | 02:41:00:160PM | Plasma | Ok | |
| 32 | 02:54:00:570PM | Plasma | Ok | |
| 33 | 03:02:36:130PM | Plasma | Ok | |
| 34 | 03:17:45:610PM | Plasma | Ok | |
| 35 | 03:30:33:750PM | Plasma | Ok | |
| 36 | 03:39:26:930PM | Plasma | Ok | |
| 37 | 03:52:44:350PM | Plasma | Ok | |
| 38 | 04:08:42:330PM | Plasma | Ok | |
| 39 | 04:20:56:030PM | Plasma | Ok | |
| 40 | 04:34:39:030PM | Plasma | Ok | |
| 41 | 04:47:17:910PM | Plasma | Ok | |
| 42 | 04:58:35:100PM | Plasma | Ok | |