| Miniproposals | ||||||||||
|
| Operators | |
| Session leader(s): | Jim Irby |
| Physics operator(s): | Joseph Snipes |
| Engineering operator(s): | Bill Cochran,Gary Dekow |
| Engineering Operator Run Comment |
| MP 298A, Plasma Conditioning; PO: Snipes; SL: Irby; EO:Dekow/Cochran |
| Session Leader Plans |
| Physics Operators Plans |
| Session Leader Summaries |
| Entered: Jul 7 2004 03:49:28:803PM |
| Author: To Be Determined |
| Run Summary for 1020625 Plasma Startup PO: Snipes EO: Cochran/Dekow SL: Irby We had no duds today indicating at least to me that the sparker is neccessary to produce "reliable" fizzles. On the other hand, fixing flux loop 25 was neccessary to produce plasmas. There is no indication that argon in the prepuff does us any good at all. It was turned off early in the run without affecting plasma startup. We continued development of the double null configuration today with very good results. Plasmas with triangularites of 0.8 were produced and used to help cleanup the machine. The carbon II levels are now very low, however the H-to-D levels are still very high. Since we are turning off all gas puffs beyond 200 ms, the high H-to-D is probably a result of low D rather than high H. We will run some higher density shots during the next run to help verify this assumption. Even without an external gas souce, the density continues to rise throughout the shot (peaking at 6-7e19/m^2). As the machine cleans up, we should eventually observe falling densities even from this low starting point. On shot 26 we enabled the new pumping stack "gatevalve closed in PULSE" feature. The pumping stack gatevalves closed as expected, but unfortunately diagnostic valves closed also. The pressure rose to about 4 mTorr after the shot. Some interesting things were going on with the b-bottom, e-bottom, and e-top gauges during this shot that Brian may want to look at. Since the TCI gatevalve closed in PULSE, the density feedback turned the gas full on until 200 ms. So this shot will not be easy to compare with shots under density control. The 4 mTorr pressure with a 4000 l volume indicates about 16 Torr-l of gas was produced during the shot. Our gas valve injected about 60 Torr-l/s * 0.200 s or 12 Torr-l of gas; very approximately, indicating about a 4 Torr-l wall inventory. During ECDC following the run mass 3, 28, 32, among others were a factor of 2 or 3 higher than after run 1020624, possibly indicating we were moving material around the machine during our first cleanup attempts. |
| Physics Operator Summaries |
| Entered: Jul 7 2004 04:37:14:910PM |
| Author: To Be Determined |
| Engineering Setup for Tuesday, JUNE 25, 2002 Continuation of MP 298A SL: Irby PO: Snipes ECDC in D2 overnight, stopping 2 hours before the run Run Begins at 9:00 and ends at 17:00 Power systems setup the same as for Shot 1020621025 Gas setup: B-Top 6 psi D2 Hybrid Enabled (PG4) B-side lower 1 psi Ar Hybrid Enabled (PG1) B-side upper 10 psi D2 Hybrid DISABLED (PG2, for ECDC) C-Side 30 psi D2 Hybrid Enabled (PG3) J-Bottom leave as is Enable the following gate valves, assuming no vacuum problems: ECE, DNB RF Setup: None RUN PLAN: We will attempt breakdown without the sparker using argon prepuffs as on 1020621025. If successful, we will continue plasma conditioning and develop higher triangularity and double null equilibria. If clearly unsuccessful, we may abandon plasma operation and do DNB into gas tests for MSE calibration similar to 1010720012 or install a new sparker. Summary: There were a number of computer problems, some subtle flux loop 25 discrepancies, and some density feedback problems, but we still managed to get 8 good plasmas. When the density worked, we got nice full length plasmas with little or no disruptions much to Granetz' dismay. We succeeded in getting very high triangularity double null plasmas with upper and lower triangularities > 0.8 and kappa > 1.8. Good shots were 2, 16-18, 21, 24-26. It seems that more gas was needed than last year with an optimum around 30 ms duration prepuff. Shot 1: Loaded shot 1020621025 with 0.04 s prepuff of Argon at -0.5 s together with a similar D prepuff. Fizzle! Shot 2: Reduced Br0 from 1 mT to 0.5 mT. Good shot ramped all the way down. Shot 3: Increased triangularity by moving RXL and RXU to the left (more negative) by 1 cm. Fizzle! Shot 4: Br0 and Bz were too negative on shot 3 for some reason. So, I've returned Br0 to 1 mT and increased EF4 from -1311 A to -1280 A at breakdown. Fizzle again! Shot 5: Increased Br0 again by 0.5 mT to 1.5 mT and it seems I slightly overshot the desired Bz so I've reduced EF4 to -1295 A. Shot 6: Increased Br0 again by 0.5 mT to 1.5 mT and reduced EF4 to -1320 A. Fizzle! Shot 7: Increased Br0 again by 0.5 mT to 2.0 mT. Reduced prepuff from 40 ms to 25 ms on both the argon and deuterium valves. Fizzle! Shot 8: Reduced EF4 to -1340 A. Fizzle! Shot 9: Reduced Br0 by 0.5 mT to 1.5 mT and turned off argon. Fizzle! Shot 10: Reduced Br0 by another 0.5 mT to 1.0 mT. Fizzle! Shot 11: Raised prepuff to 34 ms duration deuterium only. Increased Br0 by 1 mT to 2.0 mT. Fizzle! Shot 12: Raised EF4 current to -1310 A. Fizzle! Shot 13: Raised Br0 by another mT to 3 mT and increased prepuff back to 40 ms duration. Fizzle! Shot 14: Reduced Br0 to 1.5 mT and increased EF4 to -1295 A. Dud! No gas! Shot 15: Fizzle again. Shot 16: Reduced EF4 current to -1310 A. Good shot. Got high triangularity with a brief double null at 1.42 s. Shot 17: Reduced prepuff to 28 ms duration. Increased lower triangularity by reducing RXL by 1 cm to -2 cm. Also put in an outward ramp in RXU to compensate for the increasing triangularity late in the shot. Computer hang up but otherwise a nice full length shot. Some data lost. Shot 18: Try again with a slight change in the RXU ramp to increase the upper triangularity a bit more. Good shot again ramps all the way down. Shot 19: Reduced nl04 to 3 x 10^19 m^-2 after 0.5 s. Reduced ZXU by 1 cm down to 2.0 cm during the flattop to increase the upper triangularity. Computer hang up. No fields. Shot 20: Fizzle! Shot 21: Increased prepuff to 34 ms duration and reduced EF4 current to -1325 A. Good shot. Upper triangularity 0.86, lower triangularity 0.82, elongation 1.83 in double null briefly. Shot 22: Density feedback failed causing large amounts of gas to enter the plasma and a disruption at 0.38 s. Shot 23: Density feedback turned off after 0.2 s to avoid another gas problem. Fizzle! Shot 24: Density feedback still off after 0.2 s to avoid another gas problem. Reduced prepuff to 25 ms duration. Good shot. Shot 25: Repeat. Good shot. Shot 26: Repeat with the main pump gate valves staying closed after the pulse to look for how much gas evolves from the walls by following the neutral pressure gauges. Good shot despite the fact that the gate valves closed on all diagnostics during the shot so the density feedback failed again, but only until 0.2 s since the feedback was turned off afterward. Shot 27: Raised ZCUR to 0.01 to make an upper null plasma with high triangularity. Fizzle! |
| Session Leader Comments | |||
| Jun 25 2002 09:11:22:310AM | Jim Irby | This run will be a continuation of 298A . continue vessel cleanup . continue development of upper null configuration . vacuum conditioning of j-port antenna if possible | |
| Jun 25 2002 09:24:51:877AM | 1020625001 | Jim Irby | Fizzle |
| Jun 25 2002 09:33:38:483AM | 1020625002 | Jim Irby | Plasma into rampdown Looks like sparker is working Problems with interferometer H-to-D did not function on this or the last shot Carbon at .004 |
| Jun 25 2002 09:55:59:270AM | 1020625003 | Jim Irby | fizzle |
| Jun 25 2002 10:24:50:220AM | 1020625004 | Jim Irby | fizzle Earl found power supply problem with H/D camac |
| Jun 25 2002 10:39:02:053AM | 1020625006 | Jim Irby | Earl has fixed H/D Fizzle CII is .004 Lost Earl's power supply again |
| Jun 25 2002 11:04:37:687AM | 1020625007 | Jim Irby | Joe reduced gas significantly, both Ar and D2. Strong fizzle |
| Jun 25 2002 11:29:08:787AM | 1020625009 | Jim Irby | Stong fizzle with bounce w/o argon. |
| Jun 25 2002 11:47:31:690AM | 1020625010 | Jim Irby | Another fizzle. |
| Jun 25 2002 02:24:15:853PM | 1020625016 | Jim Irby | Very nice plasma with high triangularity H to D high at 48% at end of shot Carbon very low .002 |
| Jun 25 2002 02:26:40:310PM | 1020625017 | Jim Irby | Another good plasma, but lost some of the data H-to-D 50% |
| Jun 25 2002 03:09:20:733PM | 1020625019 | Jim Irby | Very nice discharge H-to-D 50 to 60% --- |
| Jun 25 2002 03:20:54:767PM | 1020625021 | Jim Irby | Good plasma H-to-D 50 to 70% Density still rising during shot |
| Jun 25 2002 03:56:51:370PM | 1020625022 | Jim Irby | Lost plasma because of density feedback problem High density at end with corresponding low H-to-D |
| Jun 25 2002 04:09:56:687PM | 1020625023 | Jim Irby | Fizzle -- CII way up at .015 following last disruption |
| Jun 25 2002 04:38:40:107PM | 1020625024 | Jim Irby | Good shot. No gas after .2 s per programming H-to-D very high 50 to 90% |
| Jun 25 2002 04:58:21:563PM | 1020625026 | Jim Irby | Eabled gatevalve closure on PULSE. Got the pressure data, but the diagnostic gatevalves also closed in pulse. |
| Physics Operator Comments | |||
| Jun 25 2002 08:45:24:220AM | Joseph Snipes | Engineering Setup for Tuesday, JUNE 25, 2002 Continuation of MP 298A SL: Irby PO: Snipes ECDC in D2 overnight, stopping 2 hours before the run Run Begins at 9:00 and ends at 17:00 Power systems setup the same as for Shot 1020621025 Gas setup: B-Top 6 psi D2 Hybrid Enabled (PG4) B-side lower 1 psi Ar Hybrid Enabled (PG1) B-side upper 10 psi D2 Hybrid DISABLED (PG2, for ECDC) C-Side 30 psi D2 Hybrid Enabled (PG3) J-Bottom leave as is Enable the following gate valves, assuming no vacuum problems: ECE, DNB RF Setup: None RUN PLAN: We will attempt breakdown without the sparker using argon prepuffs as on 1020621025. If successful, we will continue plasma conditioning and develop higher triangularity and double null equilibria. If clearly unsuccessful, we may abandon plasma operation and do DNB into gas tests for MSE calibration similar to 1010720012 or install a new sparker. | |
| Jun 25 2002 08:46:47:267AM | Joseph Snipes | Hybrid initialized O.K. rtnode -- data loaded, A matrix responds rtnode -- data loaded, M matrix responds rtnode -- data loaded, PID matrix responds RT_NODE Done 25-JUN-2002 08:37:47.11 doing TCL command TYPE *************** END COL | |
| Jun 25 2002 08:52:32:450AM | 1020625001 | Joseph Snipes | Shot 1: Loaded shot 1020621025 with 0.04 s prepuff of Argon at -0.5 s together with a similar D prepuff. |
| Jun 25 2002 09:34:52:440AM | 1020625001 | Joseph Snipes | Shot 1: Fizzle! |
| Jun 25 2002 09:35:26:783AM | 1020625002 | Joseph Snipes | Shot 2: Reduced Br0 from 1 mT to 0.5 mT. Good shot ramped all the way down. |
| Jun 25 2002 09:40:44:307AM | 1020625003 | Joseph Snipes | Shot 3: Increased triangularity by moving RXL and RXU to the left (more negative) by 1 cm. Fizzle! |
| Jun 25 2002 09:59:29:447AM | 1020625004 | Joseph Snipes | Shot 4: Br0 and Bz were too negative on shot 3 for some reason. So, I've returned Br0 to 1 mT and increased EF4 from -1311 A to -1280 A at breakdown. Fizzle again! |
| Jun 25 2002 10:18:05:177AM | 1020625005 | Joseph Snipes | Shot 5: Increased Br0 again by 0.5 mT to 1.5 mT and it seems I slightly overshot the desired Bz so I've reduced EF4 to -1295 A. No fields due to computer hang up. |
| Jun 25 2002 10:27:13:223AM | 1020625006 | Joseph Snipes | Shot 6: Increased Br0 again by 0.5 mT to 1.5 mT and reduced EF4 to -1320 A. Fizzle! |
| Jun 25 2002 11:02:00:853AM | 1020625007 | Joseph Snipes | Shot 7: Increased Br0 again by 0.5 mT to 2.0 mT. Reduced prepuff from 40 ms to 25 ms on both the argon and deuterium valves. Fizzle! |
| Jun 25 2002 11:15:30:797AM | 1020625008 | Joseph Snipes | Shot 8: Reduced EF4 to -1340 A. Fizzle! |
| Jun 25 2002 11:23:46:980AM | 1020625009 | Joseph Snipes | Shot 9: Reduced Br0 by 0.5 mT to 1.5 mT and turned off argon. Fizzle! |
| Jun 25 2002 11:38:57:537AM | 1020625010 | Joseph Snipes | Shot 10: Reduced Br0 by another 0.5 mT to 1.0 mT. Fizzle! |
| Jun 25 2002 12:02:43:463PM | 1020625011 | Joseph Snipes | Shot 11: Raised prepuff to 34 ms duration deuterium only. Increased Br0 by 1 mT to 2.0 mT. Fizzle! |
| Jun 25 2002 12:07:03:203PM | 1020625012 | Joseph Snipes | Shot 12: Raised EF4 current to -1310 A. Fizzle! |
| Jun 25 2002 12:24:11:247PM | 1020625013 | Joseph Snipes | Shot 13: Raised Br0 by another mT to 3 mT and increased prepuff back to 40 ms duration. Fizzle! |
| Jun 25 2002 12:53:24:387PM | 1020625014 | Joseph Snipes | Shot 14: Reduced Br0 to 1.5 mT and increased EF4 to -1295 A. Dud! No gas! |
| Jun 25 2002 01:05:59:500PM | 1020625015 | Joseph Snipes | Shot 15: Fizzle again. |
| Jun 25 2002 01:33:59:900PM | 1020625016 | Joseph Snipes | Shot 16: Reduced EF4 current to -1310 A. Good shot. Got high triangularity with a brief double null at 1.42 s. |
| Jun 25 2002 02:25:42:057PM | 1020625017 | Joseph Snipes | Shot 17: Reduced prepuff to 28 ms duration. Increased lower triangularity by reducing RXL by 1 cm to -2 cm. Also put in an outward ramp in RXU to compensate for the increasing triangularity late in the shot. Computer hang up but otherwise a nice full length shot. Some data lost. |
| Jun 25 2002 02:34:26:523PM | 1020625018 | Joseph Snipes | Shot 18: Try again with a slight change in the RXU ramp to increase the upper triangularity a bit more. Good shot again ramps all the way down. |
| Jun 25 2002 03:08:53:860PM | 1020625019 | Joseph Snipes | Shot 19: Reduced nl04 to 3 x 10^19 m^-2 after 0.5 s. Reduced ZXU by 1 cm down to 2.0 cm during the flattop to increase the upper triangularity. Computer hang up. No fields. |
| Jun 25 2002 03:09:13:827PM | 1020625020 | Joseph Snipes | Shot 20: Fizzle! |
| Jun 25 2002 03:47:23:607PM | 1020625021 | Joseph Snipes | Shot 21: Increased prepuff to 34 ms duration and reduced EF4 current to -1325 A. Good shot. Upper triangularity 0.86, lower triangularity 0.82, elongation 1.83 in double null briefly. |
| Jun 25 2002 03:56:04:133PM | 1020625022 | Joseph Snipes | Shot 22: Density feedback failed causing large amounts of gas to enter the plasma and a disruption at 0.38 s. |
| Jun 25 2002 04:03:13:880PM | 1020625023 | Joseph Snipes | Shot 23: Density feedback turned off after 0.2 s to avoid another gas problem. Fizzle! |
| Jun 25 2002 04:41:05:343PM | 1020625024 | Joseph Snipes | Shot 24: Density feedback still off after 0.2 s to avoid another gas problem. Reduced prepuff to 25 ms duration. Good shot. |
| Jun 25 2002 04:42:43:550PM | 1020625025 | Joseph Snipes | Shot 25: Repeat. Good shot. |
| Jun 25 2002 04:56:56:577PM | 1020625026 | Joseph Snipes | Shot 26: Repeat with the main pump gate valves staying closed after the pulse to look for how much gas evolves from the walls by following the neutral pressure gauges. Good shot despite the fact that the gate valves closed on all diagnostics during the shot so the density feedback failed again, but only until 0.2 s since the feedback was turned off afterward. |
| Jun 25 2002 05:05:42:560PM | 1020625027 | Joseph Snipes | Shot 27: Raised ZCUR to 0.01 to make an upper null plasma with high triangularity. Fizzle! |
| Jun 25 2002 05:17:44:390PM | 1020625027 | Joseph Snipes | Summary: There were a number of computer problems, some subtle flux loop 25 discrepancies, and some density feedback problems, but we still managed to get 8 good plasmas. When the density worked, we got nice full length plasmas with little or no disruptions much to Granetz' dismay. We succeeded in getting very high triangularity double null plasmas with upper and lower triangularities > 0.8 and kappa > 1.8. Good shots were 2, 16-18, 21, 24-26. It seems that more gas was needed than last year with an optimum around 30 ms duration prepuff. |
| Engineering Operator Comments | ||||
| Shot | Time | Type | Status | Comment |
| 1 | 09:07:05:070AM | Plasma | Ok | |
| 2 | 09:19:54:917AM | Plasma | Ok | |
| 3 | 09:39:25:103AM | Plasma | Ok | |
| 4 | 09:56:47:787AM | Plasma | Ok | |
| 5 | 10:10:49:430AM | Test | Bad | |
| 6 | 10:25:26:737AM | Plasma | Ok | |
| 7 | 10:49:16:943AM | Plasma | Ok | |
| 8 | 11:04:51:610AM | Plasma | Ok | |
| 9 | 11:18:58:210AM | Plasma | Ok | |
| 10 | 11:35:54:703AM | Plasma | Ok | |
| 11 | 11:49:27:067AM | Plasma | Ok | |
| 12 | 12:03:52:620PM | Plasma | Ok | |
| 13 | 12:18:32:363PM | Plasma | Bad | PF Breaker Opened |
| 14 | 12:47:06:110PM | Plasma | Ok | |
| 15 | 01:02:51:307PM | Plasma | Ok | |
| 16 | 01:23:53:620PM | Plasma | Ok | |
| 17 | 02:01:07:037PM | Plasma | Ok | |
| 18 | 02:25:55:980PM | Plasma | Ok | |
| 20 | 02:56:08:387PM | Plasma | Ok | |
| 21 | 03:11:44:707PM | Plasma | Ok | |
| 22 | 03:29:41:983PM | Plasma | Ok | |
| 23 | 03:56:32:917PM | Plasma | Ok | |
| 24 | 04:09:40:047PM | Plasma | Ok | |
| 25 | 04:28:19:200PM | Plasma | Ok | |
| 26 | 04:48:47:763PM | Plasma | Ok | |
| 27 | 05:02:54:290PM | Plasma | Ok | |