| Miniproposals | ||||||||||
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| Operators | |
| Session leader(s): | Dmitri Mossessian |
| Physics operator(s): | Robert Granetz |
| Engineering operator(s): | Bill Byford,Gary Dekow |
| Engineering Operator Run Comment |
| MP 315:JET similarity experiment;SL:Mossessian; PO:Granetz; EO:Dekow/Byf |
| Session Leader Plans |
| Physics Operators Plans |
| Session Leader Summaries |
| Entered: Jul 7 2004 03:49:30:413PM |
| Author: To Be Determined |
| Run summary for 1020904 MP315 - Developing shape for JET identity experiment. PO Granetz SL Mossessian Plan: The idea was to develop a C_Mod shape that can be reproduced on JET and attempt to obtain an EDA H-mode in this shape. The shape parameters required for JET are: lower triangularity < 0.45 upper triangularity around 0.35 elongation around 1.6 a/r= 0.3 Besides, 1.2 MA current is required to match JET 0.8 MA discharges. At this current q95 will be around 3.5, which means that achieving EDA may be difficult, although running at high density should help. The main problem in obtaining the required shape on C-Mod is the small inverse aspect ratio. To get epsilon=0.3 we were going to try to increase the inner gap, while keeping the outer gap constant to maintain efficient RF coupling. After obtaining the configuration with minimum possible epsilon and required triangularities and elongation we were going to scan the density up attempting to get an EDA H-mode. Summary of the results: Only D and E antennae were available for on-axis heating, which limited the amount of RF power that can be launched into the plasma to < 3 MW. We were moving ahead just fine up to shot 7, tweaking the shape, getting close to the target epsilon and triangularities. That shot had ELM-free H-modes and the shape was not quite as we need it - when we increased inner gap to get lower epsilon, the elongation went up to 1.7 and upper triangularity was down at 0.32 (improved from shot 5 with upper_delta=0.3). So we decided that we need to increase target density and improve shape control. Unfortunately, things seemed to stop working after shot 7. Shot 8 was a fizzle. On shot 9 EF1U got to its limit early in the shot and some programming was done to improve the situation but was not loaded until shot 12, which did not go because of the power supply failure. Shot 13 was a test, shot 14 went OK but there was only 1 MW of RF available, so there was no H-mode. On shot 15 there seemed to be some density feedback problems, 16 was a fizzle and on shot 17 the K-port gate valve opened and the machine went up to air thus ending the run prematurely. Achievements: (the list is not going to be long) - got ELM-free H-mode with decent pedestal measurements at epsilon=0.31, delta_upper=0.32, delta_lower=0.46, Ip=1.2 MA Still needs to be done: - Attempt better shape control to keep deltas and kappa at target values while getting right epsilon. That seems to be a problem, but some more work can still be done before giving up. - Density scan at high current (1.2 MA) to see what density will produce EDA H-mode and whether we can run the JET shape at this density. Shots to look at: 1020904002, 1020904003 - triangularities close to target, epsilon>=0.31. ELM-free H-modes, nl target 1e20. 1020904005, 1020904007 - increased CLEARIN leads to lower epsilon (0.3 - 0.31), but also lower delta_upper and higher elongation. ELM-free H-modes, same low target nl Logbook details: ---------------------------------------------------------------------------- 1020904001 mossessian SESSION_LEADER Sep 4 2002 9:38:26:006AM . . . . . . . . . . . . . . . . . . . . First shot repeats 1020719014 and has delta_upper of 0.35 and delta_lower 0.45 at 0.8 MA. RF come is at 0.6 s, heats the core to 2.5 keV, but does not produce an H-mode. We will go to 1.2 MA for the next shot, then try to increase the inner and outer gaps in steps to see what is a minimum aspect ratio we can achieve, keeping elongation constant (~ 1.6). When the desired shape is established, we will ramp the density up to achieve an EDA H-mode. ----------------------------------------------------------------------------- 1020904002 mossessian SESSION_LEADER Sep 4 2002 9:55:41:250AM . . . . . . . . . . . . . . . . . . . . 1.2 MA plasma. Triangularities drift a little, but otherwise a fine shape. Disrupts at 1.54 s (vertical instability ?) Next shot - start current rampdown at 1.3 s and decrease elongation somewhat. ----------------------------------------------------------------------------- 1020904003 granetz PHYSICS_OPERATOR Sep 4 2002 10:16:31:846AM . . . . . . . . . . . . . . . . . . . . Shot 03 -- Plasma. Ip=1.16 MA. Disrupted at t=1.35 s, just after rampdown begins. Two elm-free H-modes. Elongation is still 1.66. Low.tri=0.46. Prf=2 MW. H/D=5-7% Next shot: increase ZXU another 2 cm, decrease RXU by 0.5 mm (to keep upp.tri near 0.35), increase CLEARIN by 1 cm. Start 5 minutes of ECDC between shots now. ----------------------------------------------------------------------------- 1020904004 mossessian SESSION_LEADER Sep 4 2002 10:20:37:570AM . . . . . . . . . . . . . . . . . . . . Fizzle. ----------------------------------------------------------------------------- 1020904005 mossessian SESSION_LEADER Sep 4 2002 10:47:17:893AM . . . . . . . . . . . . . . . . . . . . Plasma. Disrupts at 1.3 s. Shape drifts somewhat - upper delta is 0.3 now, left gap is ramping up from 0.5 to 0.7 s to 2.7 cm. Elongation is up to 1.7 Try to improve the shape for the next shot. ----------------------------------------------------------------------------- 1020904005 granetz PHYSICS_OPERATOR Sep 4 2002 10:50:57:163AM . . . . . . . . . . . . . . . . . . . . Shot 05 -- Plasma. 1.15 MA, disrupted at 1.3 s. Inner gap increased to 2.3-2.8 cm, and a/R=0.305, which is getting close. But kappa rose to 1.7, which made it vertically unstable. Outer gap also increased to 1.5 cm. Need to move RCUR out a little for stability and gap. Two elm-free H-modes. H/D=5-6% Next shot: move RCUR out 2 mm (reduce outer gap by 4 mm). Tweak early CLEARIN to make more constant. Reduce pre-fill gas puff by 2 ms since I ECDC'd between shots again. Did 4 minutes of ECDC between shots. ----------------------------------------------------------------------------- 1020904006 mossessian SESSION_LEADER Sep 4 2002 11:23:49:246AM . . . . . . . . . . . . . . . . . . . . Fizzle. ----------------------------------------------------------------------------- 1020904007 mossessian SESSION_LEADER Sep 4 2002 11:25:59:516AM . . . . . . . . . . . . . . . . . . . . Plasma. Upper delta is 0.3 - needs to go up. a/R is close but need a little more adjustment. Elongation went up when we increase CLEARIN, (1.7) - try to bring it down . H-modes are ELM-free. So after the next shot we will try to go to higher density to get EDA. ----------------------------------------------------------------------------- 1020904007 granetz PHYSICS_OPERATOR Sep 4 2002 11:27:38:956AM . . . . . . . . . . . . . . . . . . . . Shot 07 -- Plasma. 1.15 MA, disrupts at 1.4 s. a/R=0.307, kappa=1.68-1.7, Prf=1+ MW. 3 H-modes. H/D=6-7%. Next shot: increase ZXU another 2 cm, increase CLEARIN later in shot, reduce RXU by 1 cm. ----------------------------------------------------------------------------- 1020904008 granetz PHYSICS_OPERATOR Sep 4 2002 11:40:47:180AM . . . . . . . . . . . . . . . . . . . . Shot 08 -- Fizzle. Next shot: increase density to nl_04=1.3e20 m-2, and increase pre-fill by 2 ms. ----------------------------------------------------------------------------- 1020904009 granetz PHYSICS_OPERATOR Sep 4 2002 12:02:40:946PM . . . . . . . . . . . . . . . . . . . . Shot 09 -- Plasma. 1.15 MA, disrupted at t=0.93 s. EF1U got to it's 5 kA limit early in the shot. No H-mode. n/ncrit=1.25. H/D=6%. Prf=1-2 MW. Next shot: reload segment 2 from shot 7, but put the density at 1.3e20 m-2. Increase gain on EF2xEF4 from 2 to 5, based on instructions from Steve Wolfe ----------------------------------------------------------------------------- 1020904010 granetz PHYSICS_OPERATOR Sep 4 2002 12:08:46:960PM . . . . . . . . . . . . . . . . . . . . Shot 10 -- Fizzle. Next shot: no PCS changes. ----------------------------------------------------------------------------- 1020904011 granetz PHYSICS_OPERATOR Sep 4 2002 12:28:35:960PM . . . . . . . . . . . . . . . . . . . . Shot 11 -- Plasma. 1.16 MA, disrupts at t=0.92 s. I don't think I loaded the PCS changes after shot 9. Therefore the ZXU and ZXL were not rolled back. Next shot: reduce pre-fill puff by 4 ms, and LOAD INTO MODEL! ----------------------------------------------------------------------------- 1020904012 granetz PHYSICS_OPERATOR Sep 4 2002 12:45:42:206PM . . . . . . . . . . . . . . . . . . . . Shot 12 -- Dud. Power supplies faulted/crowbarred during pre-charge. Alternator also had a glitch. Next shot: no changes ----------------------------------------------------------------------------- 1020904013 granetz PHYSICS_OPERATOR Sep 4 2002 1:54:23:796PM . . . . . . . . . . . . . . . . . . . . Shot 13 -- Test. 50 kA TF only. OK. ----------------------------------------------------------------------------- 1020904014 granetz PHYSICS_OPERATOR Sep 4 2002 2:19:02:850PM . . . . . . . . . . . . . . . . . . . . Shot 14 -- Plasma. 1.16 MA, disrupts at 1.27 s. Upper elongation and triangularity are just not responding to the programming of ZXU and RXU. Next shot: Steve Wolfe had us modify the controllers to use points closer to the desired (RXU,ZXU) for the reference in both the RXU and ZXU controllers. ----------------------------------------------------------------------------- 1020904015 granetz PHYSICS_OPERATOR Sep 4 2002 2:30:41:836PM . . . . . . . . . . . . . . . . . . . . Shot 15 -- Plasma. Disrupted at t=0.73 s. Lots of hard x-rays, density was too low. EFIT results may be screwed up. Next shot: increase pre-fill puff by 3 ms. ----------------------------------------------------------------------------- 1020904016 granetz PHYSICS_OPERATOR Sep 4 2002 2:39:20:083PM . . . . . . . . . . . . . . . . . . . . Shot 16 -- Fizzle. Next shot: no changes ----------------------------------------------------------------------------- 1020904017 granetz PHYSICS_OPERATOR Sep 4 2002 4:09:41:940PM . . . . . . . . . . . . . . . . . . . . Shot 17 -- Plasma. 1.16 MA, disrupted at t=1.26 s. Vacuum pumps shut down. Machine may have a leak. Chris Boswell notes that the wide1 camera sees something sitting on the divertor shelf in front of the J-antenna. Looks to me like a BN tile. A gate valve on K-port was apparently shaken open by the disruption. Aluminum foil prevented a complete up-to-air, but the machine is now contaminated with moist air. End of run. - |
| Physics Operator Summaries |
| Entered: Jul 7 2004 04:37:16:067PM |
| Author: To Be Determined |
| Physics operator summary for run 1020904 (Wednesday): Session leader: D. Mossessian Physics operator: R. Granetz Engineer in charge: G. Dekow/Bill Byford Summary: The combined requirements of small a/R and high Ip (not to mention high ne and high Prf) which are required for the proposed JET similarity could not be achieved today without hard disruptions on every shot (as I expected). This eventually took its toll on the machine, including some fizzles, a broken BN tile (probably) lying on the divertor shelf at J-port, and a machine vent due to an active gate valve at K-port that wasn't blanked off. There was also a false alarm on some alternator fault signals. Scorecard: 10 plasmas 5 fizzles 1 duds (due to power supply fault) 1 test (TF only) 0 aborted and/or screwed up by computer problems ---------- 17 total ------------------------------------------------------------------------------- Engineering setup for Wednesday 04 Sept 2002 MP 315: Develop shape (and current) for JET similarity experiment Session leader: Dmitri Mossessian Physics operator: R. Granetz ECDC overnight in D2 at 2e-4 Torr, stopping by 07:00. Set up for possible ECDC in D2 between shots. Run begins at 09:00 and ends at 17:00. Power systems the same as shot 1020719014 (0.8 MA, 5.3 T, lower single null) Gas setup: fill B-Top with 6 psi D2 Hybrid enabled (PG4) fill B-side lower with 1 psi Ar Hybrid enabled (PG1) fill B-side upper with 10 psi D2 Hybrid DISABLED (PG2) (for ECDC) fill C-side with 30 psi D2 Hybrid enabled (PG3) leave J-Bottom as is Hybrid DISABLED (PG5) Enable the following gate valves, assuming no vacuum problems: ECE, VUV. Do NOT enable the DNB gate valve. ------------------------------------------------------------------------------- RF Setup: All 4 transmitters in Run On by 07:00. ------------------------------------------------------------------------------- Run Plan: Start with shot 1020719014, which has the desired upper and lower triangularities, but the inverse aspect ratio is too high. We need to reduce this by increasing the inner gap. We also need to raise the plasma current from 0.8 to 1.2 MA. We need enough RF power to get us into H-mode. Since we want EDA H-modes, we will have to try raising the density as well. ------------------------------------------------------------------------------- ECDC was NOT done overnight, despite the request! We had 1 hr 45 min of ECDC in D2 this morning. Hybrid coldstart done; no errors found Loaded PCS segment 2 from shot 1020719014, segment 1 from last shot of yesterday (1020903026). ------------------------------------------------------------------------------- The start of the run is slightly delayed due to a 480 V indicator problem in one of the TMX supplies. Shot 01 -- Plasma. Good shot. Ip=0.8 MA, Btor=5.3 T, nl_04=1.0e20 m-2. Upper triang=0.35, lower triang=0.45, a=0.218, R0=0.687, eps=0.317, inner gap=1.8 cm, outer gap=1.0 cm. Prf=0.8-1.5 MW. No H-modes. H/D=3-4%. Next shot: increase Ip to 1.2 MA; keep all other PCS programming the same. Shot 02 -- Plasma. Ip=1.15 MA. Disrupted at t=1.54 s at full current. Ihalo=77 kA. No power supplies railed. kappa=1.67, n/ncrit=1.12. Upp.tri=0.34-0.36, Low.tri=0.46, a=0.215-0.217, R0=0.681-0.687. Prf=1 MW mostly, H/D=5-6%. Got 2 H-modes. Next shot: start Ip rampdown earlier (t=1.3 s), turn up Ip gain a little more gradually. Also raise ZXU by 1 cm to try and reduce the elongation. Shot 03 -- Plasma. Ip=1.16 MA. Disrupted at t=1.35 s, just after rampdown begins. Two elm-free H-modes. Elongation is still 1.66. Low.tri=0.46. Prf=2 MW. H/D=5-7% Next shot: increase ZXU another 2 cm, decrease RXU by 0.5 cm (to keep upp.tri near 0.35), increase CLEARIN by 1 cm. Start 5 minutes of ECDC between shots now. Shot 04 -- Fizzle. Should have dropped the gas after the ECDC. Bz is also down on this shot. Next shot: no PCS changes (no ECDC either). Shot 05 -- Plasma. 1.15 MA, disrupted at 1.3 s. Inner gap increased to 2.3-2.8 cm, and a/R=0.305, which is getting close. But kappa rose to 1.7, which made it vertically unstable. Outer gap also increased to 1.5 cm. Need to move RCUR out a little for stability and gap. Two elm-free H-modes. H/D=5-6% Next shot: move RCUR out 2 mm (reduce outer gap by 4 mm). Tweak early CLEARIN to make more constant. Reduce pre-fill gas puff by 2 ms since I ECDC'd between shots again. Did 4 minutes of ECDC between shots. Shot 06 -- Fizzle. The hell with between-shot ECDC. Next shot: add the 2 ms back to pre-fill. Add 10 amps to IC_EF4. Shot 07 -- Plasma. 1.15 MA, disrupts at 1.4 s. a/R=0.307, kappa=1.68-1.7, Prf=1+ MW. 3 H-modes. H/D=6-7%. Next shot: increase ZXU another 2 cm, increase CLEARIN later in shot, reduce RXU by 1 cm. Shot 08 -- Fizzle. Next shot: increase density to nl_04=1.3e20 m-2, and increase pre-fill by 2 ms. Shot 09 -- Plasma. 1.15 MA, disrupted at t=0.93 s. EF1U got to it's 5 kA limit early in the shot. No H-mode. n/ncrit=1.25. H/D=6%. Prf=1-2 MW. Next shot: reload segment 2 from shot 7, but put the density at 1.3e20 m-2. Increase gain on EF2xEF4 from 2 to 5, based on instructions from Steve Wolfe Shot 10 -- Fizzle. Next shot: no PCS changes. Shot 11 -- Plasma. 1.16 MA, disrupts at t=0.92 s. I don't think I loaded the PCS changes after shot 9. Therefore the ZXU and ZXL were not rolled back. Next shot: reduce pre-fill puff by 4 ms, and LOAD INTO MODEL! Shot 12 -- Dud. Power supplies faulted/crowbarred during pre-charge. Alternator also had a glitch. Next shot: no changes We had a long delay after shot 12 while the alternator signals were carefully checked. Shot 13 -- Test. 50 kA TF only. OK. Shot 14 -- Plasma. 1.16 MA, disrupts at 1.27 s. Upper elongation and triangularity are just not responding to the programming of ZXU and RXU. Next shot: Steve Wolfe had us modify the controllers to use points closer to the desired (RXU,ZXU) for the reference in both the RXU and ZXU controllers. Shot 15 -- Plasma. Disrupted at t=0.73 s. Lots of hard x-rays, density was too low. EFIT results may be screwed up. Next shot: increase pre-fill puff by 3 ms. Shot 16 -- Fizzle. Next shot: no changes Shot 17 -- Plasma. 1.16 MA, disrupted at t=1.26 s. Vacuum pumps shut down. Machine may have a leak. Chris Boswell notes that the wide1 camera sees something sitting on the divertor shelf in front of the J-antenna. Looks to me like a BN tile. A gate valve on K-port was apparently shaken open by the disruption. Aluminum foil prevented a complete up-to-air, but the machine is now contaminated with moist air. End of run. |
| Session Leader Comments | |||
| Sep 4 2002 09:38:26:007AM | 1020904001 | Dmitri Mossessian | First shot repeats 1020719014 and has delta_upper of 0.35 and delta_lower 0.45 at 0.8 MA. RF come is at 0.6 s, heats the core to 2.5 keV, but does not produce an H-mode. We will go to 1.2 MA for the next shot, then try to increase the inner and outer gaps in steps to see what is a minimum aspect ratio we can achieve, keeping elongation constant (~ 1.6). When the desired shape is established, we will ramp the density up to achieve an EDA H-mode. |
| Sep 4 2002 09:55:41:250AM | 1020904002 | Dmitri Mossessian | 1.2 MA plasma. Triangularities drift a little, but otherwise a fine shape. Disrupts at 1.54 s (vertical instability ?) Next shot - start current rampdown at 1.3 s and decrease elongation somewhat. |
| Sep 4 2002 10:20:30:087AM | 1020904003 | Dmitri Mossessian | Same as shot 2 - disrupts at the beginning of current rampdown. |
| Sep 4 2002 10:20:37:570AM | 1020904004 | Dmitri Mossessian | Fizzle. |
| Sep 4 2002 10:47:17:893AM | 1020904005 | Dmitri Mossessian | Plasma. Disrupts at 1.3 s. Shape drifts somewhat - upper delta is 0.3 now, left gap is ramping up from 0.5 to 0.7 s to 2.7 cm. Elongation is up to 1.7 Try to improve the shape for the next shot. |
| Sep 4 2002 11:23:49:247AM | 1020904006 | Dmitri Mossessian | Fizzle. |
| Sep 4 2002 11:25:59:517AM | 1020904007 | Dmitri Mossessian | Plasma. Upper delta is 0.3 - needs to go up. a/R is close but need a little more adjustment. Elongation went up when we increase CLEARIN, (1.7) - try to bring it down . H-modes are ELM-free. So after the next shot we will try to go to higher density to get EDA. |
| Sep 4 2002 12:33:51:890PM | 1020904008 | Dmitri Mossessian | fizzle |
| Sep 4 2002 12:37:23:020PM | 1020904009 | Dmitri Mossessian | Trying to increase upper delta and drop elongation + increase target nl to 1.3e20. Plasma disrupted at 0.9 s. The shape did not change much. Next shot - Bob changed EF2xEF4 gain to get better control of upper delta. |
| Sep 4 2002 12:37:32:270PM | 1020904010 | Dmitri Mossessian | Fizzle |
| Sep 4 2002 12:38:08:757PM | 1020904011 | Dmitri Mossessian | Plasma - not much different from shot 9 (latest PCS changes were not loaded) |
| Sep 4 2002 12:38:24:740PM | 1020904012 | Dmitri Mossessian | Power supply failure. |
| Sep 4 2002 02:25:00:703PM | 1020904013 | Dmitri Mossessian | Test |
| Sep 4 2002 02:25:47:877PM | 1020904014 | Dmitri Mossessian | Plasma, but upper shape is not improving. |
| Physics Operator Comments | |||
| Sep 4 2002 08:49:39:493AM | Robert Granetz | Engineering setup for Wednesday 04 Sept 2002 MP 315: Develop shape (and current) for JET similarity experiment Session leader: Dmitri Mossessian Physics operator: R. Granetz ECDC overnight in D2 at 2e-4 Torr, stopping by 07:00. Set up for possible ECDC in D2 between shots. Run begins at 09:00 and ends at 17:00. Power systems the same as shot 1020719014 (0.8 MA, 5.3 T, lower single null) Gas setup: fill B-Top with 6 psi D2 Hybrid enabled (PG4) fill B-side lower with 1 psi Ar Hybrid enabled (PG1) fill B-side upper with 10 psi D2 Hybrid DISABLED (PG2) (for ECDC) fill C-side with 30 psi D2 Hybrid enabled (PG3) leave J-Bottom as is Hybrid DISABLED (PG5) Enable the following gate valves, assuming no vacuum problems: ECE, VUV. Do NOT enable the DNB gate valve. ------------------------------------------------------------------------------- RF Setup: All 4 transmitters in Run On by 07:00. ------------------------------------------------------------------------------- Run Plan: Start with shot 1020719014, which has the desired upper and lower triangularities, but the inverse aspect ratio is too high. We need to reduce this by increasing the inner gap. We also need to raise the plasma current from 0.8 to 1.2 MA. We need enough RF power to get us into H-mode. Since we want EDA H-modes, we will have to try raising the density as well. | |
| Sep 4 2002 09:00:46:620AM | Robert Granetz | ECDC was NOT done overnight, despite the request!! We had 1 hr 45 min of ECDC in D2 this morning. Hybrid coldstart done; no errors found Loaded PCS segment 2 from shot 1020719014, segment 1 from last shot of yesterday (1020903026). | |
| Sep 4 2002 09:09:57:320AM | Robert Granetz | The start of the run is slightly delayed due to a 480 V indicator problem in one of the TMX supplies. | |
| Sep 4 2002 09:37:06:457AM | 1020904001 | Robert Granetz | Shot 01 -- Plasma. Good shot. Ip=0.8 MA, Btor=5.3 T, nl_04=1.0e20 m-2. Upper triang=0.35, lower triang=0.45, a=0.218, R0=0.687, eps=0.317, inner gap=1.8 cm, outer gap=1.0 cm. Prf=0.8-1.5 MW. No H-modes. H/D=3-4%. Next shot: increase Ip to 1.2 MA; keep all other PCS programming the same. |
| Sep 4 2002 10:16:31:847AM | 1020904003 | Robert Granetz | Shot 03 -- Plasma. Ip=1.16 MA. Disrupted at t=1.35 s, just after rampdown begins. Two elm-free H-modes. Elongation is still 1.66. Low.tri=0.46. Prf=2 MW. H/D=5-7% Next shot: increase ZXU another 2 cm, decrease RXU by 0.5 mm (to keep upp.tri near 0.35), increase CLEARIN by 1 cm. Start 5 minutes of ECDC between shots now. |
| Sep 4 2002 10:24:07:890AM | 1020904004 | Robert Granetz | Shot 04 -- Fizzle. Should have dropped the gas after the ECDC. Bz is also down on this shot. Next shot: no PCS changes (no ECDC either). |
| Sep 4 2002 10:50:57:163AM | 1020904005 | Robert Granetz | Shot 05 -- Plasma. 1.15 MA, disrupted at 1.3 s. Inner gap increased to 2.3-2.8 cm, and a/R=0.305, which is getting close. But kappa rose to 1.7, which made it vertically unstable. Outer gap also increased to 1.5 cm. Need to move RCUR out a little for stability and gap. Two elm-free H-modes. H/D=5-6% Next shot: move RCUR out 2 mm (reduce outer gap by 4 mm). Tweak early CLEARIN to make more constant. Reduce pre-fill gas puff by 2 ms since I ECDC'd between shots again. Did 4 minutes of ECDC between shots. |
| Sep 4 2002 10:59:13:037AM | 1020904006 | Robert Granetz | Shot 06 -- Fizzle. The hell with between-shot ECDC. Next shot: add the 2 ms back to pre-fill. Add 10 amps to IC_EF4. |
| Sep 4 2002 11:27:38:957AM | 1020904007 | Robert Granetz | Shot 07 -- Plasma. 1.15 MA, disrupts at 1.4 s. a/R=0.307, kappa=1.68-1.7, Prf=1+ MW. 3 H-modes. H/D=6-7%. Next shot: increase ZXU another 2 cm, increase CLEARIN later in shot, reduce RXU by 1 cm. |
| Sep 4 2002 11:40:47:180AM | 1020904008 | Robert Granetz | Shot 08 -- Fizzle. Next shot: increase density to nl_04=1.3e20 m-2, and increase pre-fill by 2 ms. |
| Sep 4 2002 12:02:40:947PM | 1020904009 | Robert Granetz | Shot 09 -- Plasma. 1.15 MA, disrupted at t=0.93 s. EF1U got to it's 5 kA limit early in the shot. No H-mode. n/ncrit=1.25. H/D=6%. Prf=1-2 MW. Next shot: reload segment 2 from shot 7, but put the density at 1.3e20 m-2. Increase gain on EF2xEF4 from 2 to 5, based on instructions from Steve Wolfe |
| Sep 4 2002 12:08:46:960PM | 1020904010 | Robert Granetz | Shot 10 -- Fizzle. Next shot: no PCS changes. |
| Sep 4 2002 12:28:35:960PM | 1020904011 | Robert Granetz | Shot 11 -- Plasma. 1.16 MA, disrupts at t=0.92 s. I don't think I loaded the PCS changes after shot 9. Therefore the ZXU and ZXL were not rolled back. Next shot: reduce pre-fill puff by 4 ms, and LOAD INTO MODEL! |
| Sep 4 2002 12:45:42:207PM | 1020904012 | Robert Granetz | Shot 12 -- Dud. Power supplies faulted/crowbarred during pre-charge. Alternator also had a glitch. Next shot: no changes |
| Sep 4 2002 01:46:53:003PM | 1020904012 | Robert Granetz | We had a long delay after shot 12 while the alternator signals were carefully checked. |
| Sep 4 2002 01:54:23:797PM | 1020904013 | Robert Granetz | Shot 13 -- Test. 50 kA TF only. OK. |
| Sep 4 2002 02:19:02:850PM | 1020904014 | Robert Granetz | Shot 14 -- Plasma. 1.16 MA, disrupts at 1.27 s. Upper elongation and triangularity are just not responding to the programming of ZXU and RXU. Next shot: Steve Wolfe had us modify the controllers to use points closer to the desired (RXU,ZXU) for the reference in both the RXU and ZXU controllers. |
| Sep 4 2002 02:30:41:837PM | 1020904015 | Robert Granetz | Shot 15 -- Plasma. Disrupted at t=0.73 s. Lots of hard x-rays, density was too low. EFIT results may be screwed up. Next shot: increase pre-fill puff by 3 ms. |
| Sep 4 2002 02:39:20:083PM | 1020904016 | Robert Granetz | Shot 16 -- Fizzle. Next shot: no changes |
| Sep 4 2002 04:09:41:940PM | 1020904017 | Robert Granetz | Shot 17 -- Plasma. 1.16 MA, disrupted at t=1.26 s. Vacuum pumps shut down. Machine may have a leak. Chris Boswell notes that the wide1 camera sees something sitting on the divertor shelf in front of the J-antenna. Looks to me like a BN tile. A gate valve on K-port was apparently shaken open by the disruption. Aluminum foil prevented a complete up-to-air, but the machine is now contaminated with moist air. End of run. |
| Engineering Operator Comments | ||||
| Shot | Time | Type | Status | Comment |
| 1 | 09:23:07:980AM | Plasma | Ok | |
| 2 | 09:40:16:340AM | Plasma | Ok | |
| 3 | 09:58:08:177AM | Plasma | Ok | |
| 4 | 10:18:17:380AM | Plasma | Ok | |
| 5 | 10:31:46:090AM | Plasma | Ok | |
| 6 | 10:52:36:903AM | Plasma | Ok | |
| 7 | 11:10:58:947AM | Plasma | Ok | |
| 8 | 11:29:13:443AM | Plasma | Ok | |
| 9 | 11:42:04:273AM | Plasma | Ok | |
| 10 | 12:04:25:840PM | Plasma | Ok | |
| 11 | 12:17:39:367PM | Plasma | Ok | |
| 12 | 12:31:44:480PM | Plasma | Bad | OH2L spurious Xbar |
| 13 | 01:49:51:430PM | Test | Ok | TF 50kAmp Test Only |
| 14 | 02:03:19:777PM | Plasma | Ok | |
| 15 | 02:17:54:300PM | Plasma | Ok | |
| 16 | 02:32:33:980PM | Plasma | Ok | |
| 17 | 02:46:58:017PM | Plasma | Ok | |