| Miniproposals | ||||||||||
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| Operators | |
| Session leader(s): | Brian Labombard |
| Physics operator(s): | Dmitri Mossessian |
| Engineering operator(s): | Bill Parkin,Bill Cochran |
| Engineering Operator Run Comment |
| MP #267 SOL fluct. Mossessian/Labombard/Cochran/Parkin. |
| Session Leader Plans |
| Physics Operators Plans |
| Session Leader Summaries |
| Entered: Jul 7 2004 03:49:25:460PM |
| Author: To Be Determined |
| 11/21/00 run: MP#267 - reversed field "Dependence of SOL Fluctuations and Particle Transport on Collisionality" - reversed field, Day 2 continued... Session Leader - B. LaBombard Phys Op - D. Mossessian ________________________________________________________________________________ Reason for today's run: The plan today was to complete the remaining portion of the second half of the Day 2 plan, covering two densities at Bt=4 tesla and three densities at 6 tesla. Even though these discharges have been tough to obtain, it was considered critical to continue pursuing them because they should help us sort out differences between Ip and q scalings of the SOL transport/turbulence. But, considering the effort that has been invested in obtaining these data, it is going to be tough for the results, however interesting they are, to match expectations. ________________________________________________________________________________ Today's plan: The plan was to make use of a 1/2 day run (starting at 2:00 p.m.) following the repair of the alternator motor. Start with shot 1001116007 Ip = 0.8 MA, Bt = 4 tesla, change density program to NL04 ~ 0.9 Good equilibrium and FSP/ASP target is essential. Take two shots at each condition to optimize scanning probe insertion depths. NL04 = 0.9, Ip = 0.8, Bt = 4 NL04 = 1.2, Ip = 0.8, Bt = 4 NL04 = 1.2, Ip = 0.8, Bt = 6 NL04 = 0.9, Ip = 0.8, Bt = 6 NL04 = 0.6, Ip = 0.8, Bt = 6 ________________________________________________________________________________ Results: We managed to complete the MP today. We got 7 shots spanning the density and field range that we wanted, most with good probe targeting and C2D4 plumes. Sanjay should have plenty of plume data for his thesis. The turbulence imaging system was also operated today (except for shot 10 with He puff off). At this time we can not report on the dependence of the SOL transport and turbulence on the the magnitude of Bt (or q, density,...) in reversed field versus normal field conditions. This will require the usual detailed analysis, which takes some time. But we now have a fairly nice reverse field database to chew on. - Many thanks to the operations crew who put up with us. We did note today something about the density 'bursts' in the SOL, which if understood, could be an important piece in the SOL transport puzzle: During previous normal Bt/Ip operation, it was noted that a 'parallel flow burst' directed away from the outer divertor (presumably along field lines) was often associated with an 'ion saturation burst' event in the SOL. In contrast, during reversed Bt/Ip operation, the 'parallel flow bursts' are now directed towards the outer divertor. Thus the simple idea that these flow bursts are caused by an 'ionization burst' in the divertor does not hold up. The observation suggests that the parallel flow bursts care about the direction of ExB in the SOL. Perhaps a tight coupling between ExB and parallel flows might exist in the SOL, even over the time evolution of the 'bursts and blobs', such that the local ExB perturbation drives primarily a 'toroidal flow burst'. But this is just idle speculation at the moment. ________________________________________________________________________________ Shot Notes: Setup for this run, unless otherwise noted: ASP and FSP N-S in Vf mode, E-W in SINGLE probe sweep mode ASP still has problem with shorts on East probe. Shot 1 - Ip =0.8, NL04 =0.9, Bt=4.0 tesla ASP and FSP scanning at .7, .95, and 1.2 seconds He puff on, C2D4 on. FSP 5+ mm outside LCFS ASP did not make it far enough. Note: parallel flow 'bursts' now are towards the divertor. Shot 2 - Ip =0.8, NL04~ 1 and ramping, Bt=4.0 tesla ASP and FSP scanning at .7, .95, and 1.2 seconds He puff on, C2D4 on. FSP 5+ mm outside LCFS Shot 3 - Ip =0.8, NL04 =0.92 and ramping, Bt=4.0 tesla ASP and FSP scanning at .7, .95, and 1.2 seconds He puff on, C2D4 on. FSP 5+ mm outside LCFS Good targeting on ASP, some arcing. Shot 4 - Ip =0.8, NL04 ~.9, Bt=6.0 tesla ASP and FSP scanning at .7, .95, and 1.2 seconds He puff on, C2D4 on. FSP 5+ mm outside LCFS Good targeting on ASP Shot 7 - Ip =0.8, NL04 ~.6 ramping to 0.8 (from He puff), Bt=6.0 tesla ASP and FSP scanning at .7, .95, and 1.2 seconds He puff on, C2D4 on. ASP goes deep Shot 9 - Ip =0.8, NL04 ~1 ramping to 1.2, Bt=6.0 tesla ASP and FSP scanning at .7, .95, and 1.2 seconds He puff on, C2D4 on. ASP goes deep Shot 10 - Ip =0.8, NL04 ~.6, Bt=6.0 tesla ASP and FSP scanning at .7, .95, and 1.2 seconds NO He puff, C2D4 on. ASP goes deep, FSP goes deep. Plumes do NOT show expected flow toward divertor with strong ExB. Strange plume seen on top camera during third scan. |
| Physics Operator Summaries |
| Entered: Jul 7 2004 04:37:12:690PM |
| Author: To Be Determined |
| Physop summary for Tuesday, November 21, run 1001121 _________________________________________________ Engineering Setup for Tuesday, November 21 In support of MP#267 SOL fluctuations SL LaBombard PO Mossessian Engineering setup: ------------------- Run begins 13:00 (or as soon as we have the alternator) and ends at 18:00 Power System Setup: Same as on 1001109022 Gas setup - fill B-top with 6 psi of D2 Hybrid enabled fill B-side lower with 1 psi of Ar Hybrid DISABLED fill B-side upper with 35 psi of D2 Hybrid DISABLED, for ECDC 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, DNB, Beast The following transmitters should be turned on 1, 2, and 4 Run Plan (LaBombard) ------------------- Start with shot 1001116007 Ip = 0.8 MA, Bt = 4 tesla Good equilibrium and FSP/ASP target is essential. Take two shots at each condition to optimize scanning probe insertion depths. NL04 = 0.9, Ip = 0.8, Bt = 4 NL04 = 1.2, Ip = 0.8, Bt = 4 NL04 = 1.2, Ip = 0.8, Bt = 6 NL04 = 0.9, Ip = 0.8, Bt = 6 NL04 = 0.6, Ip = 0.8, Bt = 6 ______________________________ ******************************************************* Scorecard: 10 shots 3 fizzles Summary: Run started at 14:00 and was rather successful. Out of 10 shots we had 3 fizzles (all because fields were wondering around).Generally, the startup was not very reliable. In most cases plasma was bouncing off outer wall at around 0.015. No major problems or PCS changes, apart from planned field and density programming (see details below). Best startups are shots 09 and 10. Details: 1001121001 Plasma. Hits the outer wall at 0.015 sec and barely survives. For next shot: nl04 -> 1.2e20, RCUR up by 0.25 at 1.5 sec trying to keep the right gap constant. 1001121002 Plasma. Bz dropped a little by itself helping the startup problem For next shot: nl04 -> 0.9e20 again. No other changes 1001121003 Plasma. Startup as in shot 1. For next shot: Drop Bz IC_EF4 1325 -> 1320. Bt to 6 T 1001121004 Plasma. Dropping Bz didn't help - still hitting outer wall at 0.017 sec For next shot: Pulse_gas4 22 msec -> 24 msec (to slow current rise), tweak right gap (RCUR down 1 mm) to keep it const, nl04 ->6e19 1001121005 Fizzle. Late breakdown and Br dropped, lifting it too high. For next shot: add 1 mT to Br offset, bring pulse_gas4 to 23 msec (just in case) 1001121006 Fizzle. Somewhat earlier breakdown than in shot 5, but Br is too high and Bz looks too low. SPANNA crushed after this shot. Started up PCS again and loaded shot 4, changing nl04 to 0.6e20. 1001121007 Plasma. Late breakdown (0.01) but nice smooth current rise. For next shot: no startup changes. NL04 ->1.2e20. RCUR down by 1 mm. 1001121008 Fizzle. Late breakdown. Steve thinks Bz too low. For next shot: IC_EF4 up 1320 ->1335 1001121009 Plasma. For next shot: nl04 -> 0.6e20 1001121010 Plasma. |
| Session Leader Comments | |||
| Nov 21 2000 02:30:43:950PM | 1001121001 | Brian Labombard | Shot 1 - Ip =0.8, NL04 =0.9, Bt=4.0 tesla ASP and FSP scanning at .7, .95, and 1.2 seconds He puff on, C2D4 on. FSP 5+ mm outside LCFS ASP did not make it far enough. Note: parallel flow 'bursts' now are towards the divertor. Next shot: Go to NL04 = 1.2 (then maybe repeat NL04=0.9 to get better target.) |
| Nov 21 2000 03:10:22:530PM | 1001121003 | Brian Labombard | Shot 3 - Ip =0.8, NL04 =0.92 and ramping, Bt=4.0 tesla ASP and FSP scanning at .7, .95, and 1.2 seconds He puff on, C2D4 on. FSP 5+ mm outside LCFS Good targeting on ASP, some arcing. Next shot: Stay at NL06=0.9, go to 6 tesla. |
| Nov 21 2000 04:41:39:793PM | 1001121004 | Brian Labombard | Shot 4 - Ip =0.8, NL04 ~.9, Bt=6.0 tesla ASP and FSP scanning at .7, .95, and 1.2 seconds He puff on, C2D4 on. FSP 5+ mm outside LCFS Good targeting on ASP Next shot: go to NL04 ~ 0.6 |
| Nov 21 2000 04:47:06:060PM | 1001121007 | Brian Labombard | Shot 7 - Ip =0.8, NL04 ~.6 ramping to 0.8 (from He puff), Bt=6.0 tesla ASP and FSP scanning at .7, .95, and 1.2 seconds He puff on, C2D4 on. ASP goes deep Next shot: go to NL04 ~ 1.2 |
| Nov 22 2000 09:44:31:327AM | 1001121007 | Brian Labombard | Shot 7 - Ip =0.8, NL04 ~.6 ramping to 0.8 (from He puff), Bt=6.0 tesla ASP and FSP scanning at .7, .95, and 1.2 seconds He puff on, C2D4 on. ASP goes deep, some shorts on third scan Next shot: go to NL04 ~ 1.2 |
| Nov 22 2000 09:45:51:043AM | 1001121009 | Brian Labombard | Shot 9 - Ip =0.8, NL04 ~1 ramping to1.2 , Bt=6.0 tesla ASP and FSP scanning at .7, .95, and 1.2 seconds He puff on, C2D4 on. Next shot: go to NL04 ~ 0.6 |
| Nov 22 2000 09:49:58:013AM | 1001121010 | Brian Labombard | Shot 10 - Ip =0.8, NL04 ~0.6 (He puff off) , Bt=6.0 tesla ASP and FSP scanning at .7, .95, and 1.2 seconds C2D4 on. ASP goes deep, some shorting on third scan. FSP plume on side camera during last scan is strange. End of run |
| Physics Operator Comments | |||
| Nov 21 2000 02:04:30:577PM | Dmitri Mossessian | Engineering Setup for Tuesday, November 21 MP#267 SOL fluct LaBombard PO Mossessian SL LaBombard Engineering setup: ------------------- Run begins 13:00 (or as soon as we have the alternator) and ends at 18:00 Power System Setup: Same as on 1001109022 Gas setup - fill B-top with 6 psi of D2 Hybrid enabled fill B-side lower with 1 psi of Ar Hybrid DISABLED fill B-side upper with 35 psi of D2 Hybrid DISABLED, for ECDC 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, DNB, Beast The following transmitters should be turned on 1, 2, and 4 Run Plan (LaBombard) ------------------- Start with shot 1001116007 Ip = 0.8 MA, Bt = 4 tesla Good equilibrium and FSP/ASP target is essential. Take two shots at each condition to optimize scanning probe insertion depths. NL04 = 0.9, Ip = 0.8, Bt = 4 NL04 = 1.2, Ip = 0.8, Bt = 4 NL04 = 1.2, Ip = 0.8, Bt = 6 NL04 = 0.9, Ip = 0.8, Bt = 6 NL04 = 0.6, Ip = 0.8, Bt = 6 ______________________________ Starting at 01:58 PM Load shot 1001116007. NL04 to 0.9e20 Coldstart OK | |
| Nov 21 2000 02:33:08:530PM | 1001121001 | Dmitri Mossessian | Plasma. Hits the outer wall at 0.015 sec and barely survives. For next shot: nl04 -> 1.2e20, RCUR up by 0.25 at 1.5 sec trying to keep the right gap constant. |
| Nov 21 2000 02:46:39:763PM | 1001121002 | Dmitri Mossessian | Plasma. Bz dropped a little by itself helping the startup problem For next shot: nl04 -> 0.9e20 again. No other changes |
| Nov 21 2000 03:17:27:327PM | 1001121003 | Dmitri Mossessian | Plasma. Startup as in shot 1. For next shot: Drop Bz IC_EF4 1325 -> 1320. Bt to 6 T |
| Nov 21 2000 03:32:06:810PM | 1001121004 | Dmitri Mossessian | Plasma. Dropping Bz didn't help - still hitting outer wall at 0.017 sec For next shot: Pulse_gas4 22 msec -> 24 msec (to slow current rise), tweak right gap (RCUR down 1 mm) to keep it const, nl04 ->6e19 |
| Nov 21 2000 03:53:42:343PM | 1001121005 | Dmitri Mossessian | Fizzle. Late breakdown and Br dropped, lifting it too high. For next shot: add 1 mT to Br offset, bring pulse_gas4 to 23 msec (just in case) |
| Nov 21 2000 04:35:48:373PM | 1001121006 | Dmitri Mossessian | Fizzle. Somewhat earlier breakdown than in shot 5, but Br is too high and Bz looks too low. SPANNA crushed after this shot. Started up PCS again and loaded shot 4, changing nl04 to 0.6e20. |
| Nov 21 2000 04:50:57:623PM | 1001121007 | Dmitri Mossessian | Plasma. Late breakdown (0.01) but nice smooth current rise. For next shot: no startup changes. NL04 ->1.2e20. RCUR down by 1 mm. |
| Nov 21 2000 05:26:13:140PM | 1001121008 | Dmitri Mossessian | Fizzle. Late breakdown. Steve thinks Bz too low. For next shot: IC_EF4 up 1320 ->1335 |
| Nov 21 2000 05:38:07:250PM | 1001121009 | Dmitri Mossessian | Plasma. For next shot: nl04 -> 0.6e20 |
| Nov 21 2000 06:06:41:483PM | 1001121010 | Dmitri Mossessian | PLasma. |
| Engineering Operator Comments | ||||
| Shot | Time | Type | Status | Comment |
| 1 | 02:09:06:873PM | Plasma | Ok | All Systems fired |
| 2 | 02:36:37:997PM | Plasma | Ok | |
| 3 | 02:56:50:450PM | Plasma | Ok | |
| 4 | 03:19:42:327PM | Plasma | Ok | |
| 5 | 03:43:29:293PM | Plasma | Ok | |
| 6 | 04:16:20:840PM | Plasma | Ok | |
| 7 | 04:39:14:123PM | Plasma | Ok | |
| 8 | 05:07:21:670PM | Plasma | Ok | |
| 9 | 05:32:33:827PM | Plasma | Ok | |
| 10 | 06:01:54:513PM | Plasma | Ok | |