| Miniproposals | ||||||||||
|
| Operators | |
| Session leader(s): | Steve Wolfe |
| Physics operator(s): | Joseph Snipes |
| Engineering operator(s): | Bill Cochran |
| Engineering Operator Run Comment |
| Startup and conditioning with normal field direction. Wolfe/Snipes/Cochr |
| Session Leader Plans |
| Physics Operators Plans |
| Session Leader Summaries |
| Physics Operator Summaries |
| Entered: Jul 7 2004 04:37:10:270PM |
| Author: To Be Determined |
| Engineering setup for Thursday, 1000406: Plasma run will begin at 09:00 and end at 17:00 Overnight ECDC in deuterium was attempted, but Mossessian turned it off early yesterday evening and never turned it back on! So, we are starting with the dirty conditions that we left off with yesterday. Power system setup as on 1000405018 Note: Fizzle detector should be on from t=0.080 to 1.7 s Gas setup - fill B-top with 6 psi of D2 Hybrid enabled fill B-side lower with 1 psi of Ar Hybrid DISABLED fill C-side with 30 psi of D2 Hybrid enabled leave J-bottom as is Hybrid DISABLED The following gate valves should be enabled, assuming no vacuum problems: ECE, VUV ------------------------------------------------------------------------------- Physics operator's setup for Thursday, 1000406 MP ? -- Startup and conditioning with normal field direction Session leader: R. Granetz Physics operator: J. Snipes The primary goals of this week's runs are: leave B-side upper as is Hybrid DISABLED 1) Get plasma with normal (negative) field 2) Machine conditioning with tokamak plasmas 3) Checkout and commissioning of available diagnostics Load from shot 1000405018 (typical 0.8 MA, 5.2 T, normal field direction) We did not get the discharge cleaning that we wanted because Mossessian turned it off last night. The result was that the machine was just as dirty as yesterday. However, given the way the plasmas disrupted early in the shot for all shots, we think there may be something sticking into the plasma. Jim Terry first saw some iron, but now he sees some unidentifiable lines and is not sure what material it may be. Molybdenum is certainly present. After many problems with the control computers (DAIGLE and SPANNA and RHONE) and all plasmas disrupting early, we decided to stop the run to install more video cameras to get views of as many locations in the vessel as possible. Then, we will run ECDC in helium to see if we see anything sticking into the plasma. It is unclear if we will run tomorrow or not. Shot,Duration(s),Ipmax(MA) Shot,Duration(s),Ipmax 1 0.579 0.833 2 0.406 0.742 3 0.369 0.768 4 0.405 0.747 5 0.000 0.036 6 0.348 0.729 7 0.437 0.750 8 0.376 0.669 9 0.323 0.716 10 0.352 0.690 11 0.000 0.036 12 0.000 0.041 13 0.000 0.003 14 0.000 0.031 15 0.168 0.584 16 0.153 0.542 17 0.375 0.721 Finished summary for 1000406 Total of 17 shots. 17 shots. 12 plasmas. 4 fizzles. 1 test. . . . . . . . . . . . . . . . . . . . . Shot 1: Copied 1000405018 except increased the prepuff from 25 ms to 28 ms duration. O.K. shot. Good startup though a bit late. No hesitation in the current rise. Disrupted at 0.6 sec. Lots of impurities. H/D ratio about 10%. . . . . . . . . . . . . . . . . . . . . Shot 2: Repeat. Not as good. Disrupted at 0.4 sec. Very dirty. . . . . . . . . . . . . . . . . . . . . Shot 3: Try lowering ZCUR by 3 mm to -1.8 cm from 0.25 s out to 1 sec. Still worse. Disrupted at 0.35 sec. Jim Terry says there is iron in the plasma! . . . . . . . . . . . . . . . . . . . . Shot 4: Try lowering ZCUR again a little bit to see if it makes it better or worse. Lowered ZCUR to -2 cm from .28 - 1 sec. Disrupted at 0.4 sec. . . . . . . . . . . . . . . . . . . . . Shot 5: Try increasing RCUR from 0.21 s onward by a few mm. Also increase CLEARIN by 2 mm to keep the plasma the same size. Fizzle! . . . . . . . . . . . . . . . . . . . . Shot 6: Br0 seems to have jumped positive by almost 1 mT. So, I will decrease the Br0 offset from -0.5 mT to -1 mT. Disrupted at 0.35 sec. . . . . . . . . . . . . . . . . . . . . Shot 7: SPANNA rebooted spontaneously. Attempted to make a more circular plasma. The result was not much better disrupting at 0.4 s. . . . . . . . . . . . . . . . . . . . . Shot 8: Try making the plasma smaller and more circular by moving RCUR in to 0.64 m and set ZCUR very close to zero. Moved ZXL to -0.05 m. There was a short delay as the central operations computers rebooted because of a switch problem. Felix is on the phone with COMPAQ now to try to resolve the problem. No better. Disrupted at 0.35 sec. . . . . . . . . . . . . . . . . . . . . Shot 9: Try making the plasma smaller and more circular. Decreased RCUR by another cm to 0.63 m and pulled ZXU and ZXL to +/- 0.08 m respectively. Disrupted just after 0.3 sec. . . . . . . . . . . . . . . . . . . . . Shot 10: Moved CLEARIN to -0.1, which required changing the factor to 1.6 x 10^-5 and after attempting to load also required changing the controller time constant from 3 to 2 sec. Then, it loaded O.K. Disrupted again at about 0.3 sec. . . . . . . . . . . . . . . . . . . . . Shot 11: Tried to make the plasma smaller and more circular. Reduced Ip to 0.6 MA. Reduced RCUR to 0.62 m, reduced CLEARIN to -0.12 m. Pulled ZXU and ZXL further out of the vessel to +/- 0.1 m, respectively. Fizzle. . . . . . . . . . . . . . . . . . . . . Shot 12: Changed Br0 offset back to -0.5 mT from -1 mT. Increased the EF4 current by another -15 A to -1280 A. Another fizzle! . . . . . . . . . . . . . . . . . . . . Shot 13: Two changes were too many. Put EF4 current back where it was at -1265 A. Try again. Computer problems caused a brief delay again where we got hung during INIT and had to back out of the shot. Now PHYSOP had to be rebooted as well. This is a no-power test shot. . . . . . . . . . . . . . . . . . . . . Shot 14: Fizzle. . . . . . . . . . . . . . . . . . . . . Shot 15: Reduced EF4 current by 25 A to -1290 A. Got plasma, but it disrupted at .165 s. Appears to be a problem with OH2U. No, it seems that I am asking it to behave badly. . . . . . . . . . . . . . . . . . . . . Shot 16: Return ZXU and ZXL to their normal values. Changed CLEARIN so that it becomes strongly inner wall limited only after about 0.2 sec. Still disrupts very early around 0.15 sec. . . . . . . . . . . . . . . . . . . . . Shot 17: Try reloading shot 1000406001 and return to "normal" plasmas. Set EF4 current to -1290 A as well. We have almost returned to shot 1. Disrupted at 0.37 sec. We decided to stop the run to install more cameras and then run ECDC to look and see if we can see what may be sticking into the plasma. It is unlikely that we will run tomorrow. |
| Session Leader Comments |
| Physics Operator Comments | |||
| Apr 6 2000 08:23:28:530AM | 1000406001 | Joseph Snipes | Engineering setup for Thursday, 1000406: Plasma run will begin at 09:00 and end at 17:00 Overnight ECDC in deuterium was attempted, but Mossessian turned it off early yesterday evening and never turned it back on! So, we are starting with the dirty conditions that we left off with yesterday. Power system setup as on 1000405018 Note: Fizzle detector should be on from t=0.080 to 1.7 s Gas setup - fill B-top with 6 psi of D2 Hybrid enabled fill B-side lower with 1 psi of Ar Hybrid DISABLED fill C-side with 30 psi of D2 Hybrid enabled leave J-bottom as is Hybrid DISABLED The following gate valves should be enabled, assuming no vacuum problems: ECE, VUV ------------------------------------------------------------------------------- Physics operator's setup for Thursday, 1000406 MP ? -- Startup and conditioning with normal field direction Session leader: R. Granetz Physics operator: J. Snipes The primary goals of this week's runs are: leave B-side upper as is Hybrid DISABLED 1) Get plasma with normal (negative) field 2) Machine conditioning with tokamak plasmas 3) Checkout and commissioning of available diagnostics Load from shot 1000405018 (typical 0.8 MA, 5.2 T, normal field direction) ------------------------------------------------------------------------------- |
| Apr 6 2000 09:15:10:513AM | 1000406001 | Joseph Snipes | Shot 1: Copied 1000405018 except increased the prepuff from 25 ms to 28 ms duration. O.K. shot. Good startup though a bit late. No hesitation in the current rise. Disrupted at 0.6 sec. Lots of impurities. H/D ratio about 10%. |
| Apr 6 2000 09:46:28:843AM | 1000406002 | Joseph Snipes | Shot 2: Repeat. Not as good. Disrupted at 0.4 sec. Very dirty. |
| Apr 6 2000 10:03:11:797AM | 1000406003 | Joseph Snipes | Shot 3: Try lowering ZCUR by 3 mm to -1.8 cm from 0.25 s out to 1 sec. Still worse. Disrupted at 0.35 sec. Jim Terry says there is iron in the plasma! |
| Apr 6 2000 10:15:46:903AM | 1000406004 | Joseph Snipes | Shot 4: Try lowering ZCUR again a little bit to see if it makes it better or worse. Lowered ZCUR to -2 cm from .28 - 1 sec. Disrupted at 0.4 sec. |
| Apr 6 2000 10:45:53:013AM | 1000406005 | Joseph Snipes | Shot 5: Try increasing RCUR from 0.21 s onward by a few mm. Also increase CLEARIN by 2 mm to keep the plasma the same size. Fizzle! |
| Apr 6 2000 11:08:06:640AM | 1000406006 | Joseph Snipes | Shot 6: Br0 seems to have jumped positive by almost 1 mT. So, I will decrease the Br0 offset from -0.5 mT to -1 mT. Disrupted at 0.35 sec. |
| Apr 6 2000 11:48:04:140AM | 1000406007 | Joseph Snipes | Shot 7: SPANNA rebooted spontaneously. Attempted to make a more circular plasma. The result was not much better disrupting at 0.4 s. |
| Apr 6 2000 11:48:24:577AM | 1000406008 | Joseph Snipes | Shot 8: Try making the plasma smaller and more circular by moving RCUR in to 0.64 m and set ZCUR very close to zero. Moved ZXL to -0.05 m. There was a short delay as the central operations computers rebooted because of a switch problem. Felix is on the phone with COMPAQ now to try to resolve the problem. No better. Disrupted at 0.35 sec. |
| Apr 6 2000 12:04:58:187PM | 1000406009 | Joseph Snipes | Shot 9: Try making the plasma smaller and more circular. Decreased RCUR by another cm to 0.63 m and pulled ZXU and ZXL to +/- 0.08 m respectively. Disrupted just after 0.3 sec. |
| Apr 6 2000 12:18:38:233PM | 1000406010 | Joseph Snipes | Shot 10: Moved CLEARIN to -0.1, which required changing the factor to 1.6 x 10^-5 and after attempting to load also required changing the controller time constant from 3 to 2 sec. Then, it loaded O.K. Disrupted again at about 0.3 sec. |
| Apr 6 2000 12:44:40:500PM | 1000406011 | Joseph Snipes | Shot 11: Tried to make the plasma smaller and more circular. Reduced Ip to 0.6 MA. Reduced RCUR to 0.62 m, reduced CLEARIN to -0.12 m. Pulled ZXU and ZXL further out of the vessel to +/- 0.1 m, respectively. Fizzle. |
| Apr 6 2000 12:52:46:607PM | 1000406012 | Joseph Snipes | Shot 12: Changed Br0 offset back to -0.5 mT from -1 mT. Increased the EF4 current by another -15 A to -1280 A. Another fizzle! |
| Apr 6 2000 01:47:28:983PM | 1000406013 | Joseph Snipes | Shot 13: Two changes were too many. Put EF4 current back where it was at -1265 A. Try again. Computer problems caused a brief delay again where we got hung during INIT and had to back out of the shot. Now PHYSOP had to be rebooted as well. This is a no-power test shot. |
| Apr 6 2000 03:33:58:013PM | 1000406014 | Joseph Snipes | Shot 14: Fizzle. |
| Apr 6 2000 02:30:13:920PM | 1000406015 | Joseph Snipes | Shot 15: Reduced EF4 current by 25 A to -1290 A. Got plasma, but it disrupted at .165 s. Appears to be a problem with OH2U. No, it seems that I am asking it to behave badly. |
| Apr 6 2000 02:39:33:357PM | 1000406016 | Joseph Snipes | Shot 16: Return ZXU and ZXL to their normal values. Changed CLEARIN so that it becomes strongly inner wall limited only after about 0.2 sec. Still disrupts very early around 0.15 sec. |
| Apr 6 2000 03:11:43:297PM | 1000406017 | Joseph Snipes | Shot 17: Try reloading shot 1000406001 and return to "normal" plasmas. Set EF4 current to -1290 A as well. We have almost returned to shot 1. Disrupted at 0.37 sec. |
| Apr 6 2000 03:23:40:483PM | 1000406017 | Joseph Snipes | We decided to stop the run to install more cameras and then run ECDC to look and see if we can see what may be sticking into the plasma. It is unlikely that we will run tomorrow. |
| Engineering Operator Comments | ||||
| Shot | Time | Type | Status | Comment |
| 1 | 09:02:19:327AM | Plasma | Ok | |
| 2 | 09:35:31:013AM | Plasma | Bad | OH1 Self Powered Circuit Fired |
| 3 | 09:52:41:250AM | Plasma | Ok | |
| 4 | 10:08:53:593AM | Plasma | Ok | |
| 5 | 10:43:09:733AM | Plasma | Ok | |
| 6 | 11:00:39:090AM | Plasma | Ok | |
| 7 | 11:15:44:467AM | Plasma | Ok | |
| 8 | 11:45:25:403AM | Plasma | Ok | |
| 9 | 12:01:00:920PM | Plasma | Ok | |
| 10 | 12:15:13:560PM | Plasma | Ok | |
| 11 | 12:36:08:310PM | Plasma | Ok | |
| 12 | 12:49:41:653PM | Plasma | Ok | |
| 13 | 01:05:01:780PM | Test | Ok | data system test only |
| 14 | 02:03:19:593PM | Plasma | Ok | |
| 15 | 02:16:26:390PM | Plasma | Ok | |
| 16 | 02:36:39:483PM | Plasma | Ok | |
| 17 | 03:09:00:513PM | Plasma | Ok | |