Miniproposals

Miniproposal: 222 Date Filed: 1/13/1999 Title: Impurity Compression and Enrichment Studies First Author: John Goetz Session Leader: Spencer Pitcher (shots 1-25)

Engineering Operator Run Comment

MP# 222/Rowan,Silva

Session Leader Plans

Physics Operators Plans

Session Leader Summaries

Entered: Jul 7 2004 03:49:21:070PM

Author: To Be Determined

RUN 990902 MP 222 Impurity Compression and Enrichment...... (N2) SESSION LEADER: Spencer Pitcher PHYS OP: Bill Rowan ORIGINAL PLAN: PURPOSE: To explore the effect of the flapper on screening of a non-recycling impurity (N2) We will puff N2 through the ninja system from a number of locations on the machine with and without the flapper open. The primary puff locations will be the outside midplane and the outer divertor plate. We will run pairs of discharges, first with flapper closed for the entire discharge and then flapper open in a comparison discharge. In a few cases we will open/close the flaps during the discharge. start: like 990901015, Ip = 1.0 MA, Bt = 5.4 T, D2, but with nl04 target 1.0e20, N2 thru the ninja system vary plasma density, 0.7e20, 1.4e20 ------------------------------------------------------------------- Summary: The machine ran quite well today...very few fizzles/faults. We operated at three nominal discharge densities (low nl04 = 0.7, med nl04 = 1.0, high nl04 = 1.8). We varied the N2 gas puffing position from the outside midplane, to the outer divertor, to the private flux region, to the inside midplane. We ran discharges with either the flappers open or closed for the entire discharge. We again found a number of null results for the effect of the flappers. No major differences were observed in any discharges comparing flaps closed with flaps open.....we focussed primarily on nitrogen spectroscopy, ie chromex (N II) in the divertor and main chamber and the MacPherson in the main chamber (li-like). Nitrogen signals were also obtained on the divertor RGA, the omegatron, and visible bremm (which looks right at the AB limiter gas puff location). This null result was obtained despite the usual factor of 2 effect of the flapper on the divertor neutral pressure. (Remember that recycling impurities are also affected by the flaps, similar to the effect on D2). Evidently, the null result with nitrogen suggests that nitrogen does not pass through the bypass (as recycling gases do, e.g. argon)...this is consistent with nitrogen begin a non-recycling species. We were hoping to observe the effect of the deuteron flow that the flapper (when open) supposedly induces towards the plate....this might manifest itself as better screening when puffing N2 from the divertor.....however, no effect was observed. The most striking results of the day were related to the different screening properties at different N2 release locations, irrespective of the flapper. N2 released from the AB limiter was very effective at reaching the core, while N2 released from the outer divertor, private flux region and inner midplane were much less effective. The inner wall result is surprising, but consistent with earlier C-Mod results which have shown preferred streaming of injected impurities at the inside midplane towards the divertor. A detailed run summary is below: --------------------------------------------------------- ***shot 1 reference shot, no N2 puff, no flaps, density set for nl04 = 1.0, but drifted up, guess the walls are loaded, background N2 levels low as seen on MPher, Chromex, RGA note: ECDC did not go last night ***shot 2 repeat, plus N2 gas thru ninja Ninja plenun 140 Torr N2 ninja settings: trig 0.6, dur 0.3, AB Lim N2 seen on Omegatron, Chromex, VisBremm, not seen on MPher ***shot 3 repeat increase ninja plenum to 316 Torr, same program N2 seen on Omega, Chromex, VisBre, MPher (divertor view), RGA delta Zeff = 0.1 ***shot 4 repeat MPher (main chamber)....good signal Omegatron out ***shot 5 repeat, flaps open for whole shot Omegatron in little difference in N2 levels on chromex, MPher ***shot 6 repeat, flaps closed, N2 gas puff moved to B31-038 (outer divertor) no chromex data, MPher signal down significantly ***shot 7 repeat, flaps open huge chromex signal MPher essentially identical to shot 6 ***shot 8 repeat, flaps closed for chromex chromex similar between shots 6,8 pause for some gas puff tests test shot 2120 B31-038 test shot 2121 AB Lim test shot 2122 B26-019 ***shot 9 move gas puff to B26-019 (private flux region) MPher the same as shot 8 chromex ...big changes from shot 8 ***shot 10 repeat flapper open MPher.....no difference between shots 9 and 10 chromex little difference seen between shots 9 and 10 ***shot 11 repeat flapper close move gas puff to B16-001 (inner wall) ...NO PLASMA... ***shot 12 repeat strong streaming seen at inner wall towards divertor good ASP and FSP data MPher lower than shot 10, also prompter chromex similar to shot 10 (a little higher) ***shot 13 repeat, flappers open MPher: no difference between 12 and 13 chromex: small differences between 12 and 13 Boswell sees a Halpha blob above a flapper (comparing 12 and 13) the delta-intensity is around 15% ***shot 14 repeat, N2 off, flappers closed, background/baseline test pause for some gas puff tests test shot 2123 B16-001 test shot 2124 B31-038 (outer divertor) ***shot 15 raise density, nl04 = 1.8 flappers closed, N2 puff thru outer divertor B31-038 density doesn't reach flat-top until after 1.0 s ***shot 16 repeat, but.. change density demand to flat-top earlier ***shot 17 repeat, flappers open ***shot 18 repeat, flappers open, move gas puff to AB lim ***shot 19 repeat, flappers closed, no N2 puff no plasma ***shot 20 no plasma ***shot 21 finally plasma ***shot 22 lower density, nl04 = 0.7, N2 puff thru B31-038 (outer divertor) flapper closed pause for gas puff test test shot 2125 B31-038 (outer divertor) test shot 2126 AB Lim ***shot 23 repeat at low density, nl04 = 0.75, N2 puff thru B31-038 (outer divertor) flapper open ***shot 24 repeat at low density, nl04 = 0.84, N2 puff thru A-B Limiter flapper closed ***shot 25 repeat at low density, nl04 = 0.9, N2 puff thru A-B Limiter flapper open -------------------------------------------------- after the run Brian LaBombard did gas puff tests: 2127 labombard EDGE Sep 2 1999 5:34:30:500PM . . . . . . . . . . . . . . . . . . . . N2 puff test shot through A-B limiter 263 torr fill pressure large plenum trigger at .6, duration 0.3 4.7e-7 before puff, 1.1e-4 max torus pressure after puff. 1.59 torr change in plenum pressure. ----------------------------------------------------------------------------- 2128 labombard EDGE Sep 2 1999 5:37:20:686PM . . . . . . . . . . . . . . . . . . . . N2 puff test shot through B31-038 262 torr fill pressure large plenum trigger at .6, duration 0.3 4.5e-7 before puff, 2.5e-4 max torus pressure after puff. 1.62 torr change in plenum pressure.

Physics Operator Summaries

Entered: Jul 7 2004 04:37:09:207PM

Author: To Be Determined

Physop Report for Thursday, September 2, 1999 SL: S. Pitcher/J. Goetz PO: W. Rowan EO: F. Silva/B. Cochran The purpose of the run was to continue MP#222 (Impurity Compression and Enrichment Studies) and to continue RF conditioning as possible at the end of the discharge. Progress toward completion of MP 222 is described in the Session Leader Summary The SL requested that ECDC be run all night, but it ran for just 6 minutes. It was turned on immediately after the run for test and then turned off for evening maintenance. Through misunderstanding it was not turned on again after the maintenance was completed. The run began at approximately 9am as planned. At the beginning of the run, shot 990901015 was loaded. The shot was lengthened from 1.4 s to 1.5 s to accomodate RF conditioning at the end of each shot. For MP 222, the density was varied. Throughout the run, flappers were opened and closed and the Ninja system was used to puff gas. Both flappers and Ninja were under the control of the Session Leader, and their operation is described in that summary. Density control was adequate, but seemed to drift up a bit after about 1 s. Perhaps this was due to the lack of ECDC. There were two fizzles. It was suspected that Bz was too low on the first fizzle. As Bz and R looked okay for the previous few shots, no changes were made and the next shots were good. A small correction to Bz was made after the second fizzle because the shots just before the fizzle seemed to vary. There was one disruption that was probably due to injection of impurities due to RF conditioning. There was one TF malfunction. The run ended as planned at approximately 5pm. Engineering setup Setup power supplies from 990901015. Gas setup - fill B-top with 6 psi of D2 Hybrid enabled fill B-side lower with 1 psi of N2 Hybrid DISABLED fill B-side upper with 6 psi of H2 Hybrid DISABLED fill C-side with 30 psi of D2 Hybrid enabled leave J-bottom as is Hybrid DISABLED Shot by shot results. Shot 001. Plasma. Shot 002. Plasma Shot 003. Plasma Shot 004. Plasma Shot 005. Plasma Shot 006. Plasma Shot 007. Plasma. Shot 008. Plasma Shot 009. Plasma Shot 010. Plasma. Shot 011. Fizzle Shot 012. Plasma Shot 013. Plasma Shot 014. Disruption at 1.5 s Shot 015. Plasma Shot 016. Plasma Shot 017. Plasma Shot 018. Plasma Shot 019. TF malfunction Shot 020. Fizzle Shot 021. Plasma Shot 022. Plasma Shot 023. Plasma Shot 024. Plasma Shot 025. Plasma Scorecard Plasmas 21 Duds 0 Fizzles 2 Disruptions 1 Engineering malfunctions 1 Total 25

Session Leader Comments
Sep 2 1999 09:26:53:450AM		Spencer Pitcher	RUN 990902 MP 222 Impurity Compression and Enrichment...... (N2) SESSION LEADER: Spencer Pitcher PURPOSE: To explore the effect of the flapper on screening of a non-recycling impurity (N2) We will puff N2 through the ninja system from a number of locations on the machine with and without the flapper open. The primary puff locations will be the outside midplane and the outer divertor plate. We will run pairs of discharges, first with flapper closed for the entire discharge and then flapper open in a comparison discharge. In a few cases we will open/close the flaps during the discharge. start: like 990901015, Ip = 1.0 MA, Bt = 5.4 T, D2, but with nl04 target 1.0e20, N2 thru the ninja system Essential Diagnostics (1) Lithium-like nitrogen as measured by the MacPherson (2) N II (463 nm) Chromex trained on various locations in the divertor and main chamber (3) N2 divertor RGA (4) nitrogen peaks on the Omegatron (5) Zeff VB Other goals (depending on time available): (1) similar experiments (N2 screening) in Ohmic H-modes, like 990831027 (TF ramp down to 4.0 T) (2) investigate how toroidally localized the effect of the flappers is on the neutral pressure....i.e. we will flap only flaps B and C to see the effect on the B bottom pressure vary plasma density, 0.7e20, 1.4e20
Sep 2 1999 09:45:12:903AM	990902001	Spencer Pitcher	reference shot, no N2 puff, no flaps, density set for nl04 = 1.0, but drifted up, guess the walls are loaded, background N2 levels low as seen on MPher, Chromex, RGA
Sep 2 1999 10:14:44:107AM	990902002	Spencer Pitcher	repeat, plus N2 gas thru ninja Ninja plenun 140 Torr N2 ninja settings: trig 0.6, dur 0.3, AB Lim N2 seen on Omegatron, Chromex, VisBremm, not seen on MPher
Sep 2 1999 10:36:41:967AM	990902003	Spencer Pitcher	repeat increase ninja plenum to 316 Torr, same program N2 seen on Omega, Chromex, VisBre, MPher (divertor view), RGA delta Zeff = 0.1
Sep 2 1999 10:37:38:310AM	990902004	Spencer Pitcher	repeat MPher (main chamber)....good signal Omegatron out
Sep 2 1999 11:09:12:030AM	990902005	Spencer Pitcher	repeat, flaps open for whole shot Omegatron in little difference in N2 levels on chromex, MPher
Sep 2 1999 11:29:58:250AM	990902006	Spencer Pitcher	repeat, flaps closed, N2 gas puff moved to B31-038 (outer divertor) no chromex data, MPher signal down significantly
Sep 2 1999 11:41:19:857AM	990902007	Spencer Pitcher	repeat, flaps open huge chromex signal MPher essentially identical to shot 6
Sep 2 1999 12:14:28:730PM	990902008	Spencer Pitcher	repeat, flaps closed for chromex chromex similar between shots 6,8 pause for some gas puff tests test shot 2120 B31-038 test shot 2121 AB Lim test shot 2122 B26-019
Sep 2 1999 12:54:41:763PM	990902009	Spencer Pitcher	move gas puff to B26-019 (private flux region) MPher the same as shot 8 chromex ...big changes from shot 8
Sep 2 1999 01:21:02:450PM	990902010	Spencer Pitcher	repeat flapper open MPher.....no difference between shots 9 and 10 chromex little difference seen between shots 9 and 10
Sep 2 1999 12:57:31:623PM	990902011	Spencer Pitcher	repeat flapper close move gas puff to B16-001 (inner wall) ...NO PLASMA...
Sep 2 1999 01:34:10:280PM	990902012	Spencer Pitcher	repeat strong streaming seen at inner wall towards divertor good ASP and FSP data MPher lower than shot 10, also prompter chromex similar to shot 10 (a little higher)
Sep 2 1999 03:43:55:263PM	990902013	Spencer Pitcher	repeat, flappers open MPher: no difference between 12 and 13 chromex: small differences between 12 and 13 Boswell sees a Halpha blob above a flapper (comparing 12 and 13) the delta-intensity is around 15%
Sep 2 1999 02:16:43:530PM	990902014	Spencer Pitcher	repeat, N2 off, flappers closed, background/baseline test pause for some gas puff tests test shot 2123 B16-001 test shot 2124 B31-038 (outer divertor)
Sep 2 1999 02:29:24:340PM	990902015	Spencer Pitcher	raise density, nl04 = 1.8 flappers closed, N2 puff thru outer divertor B31-038 density doesn't reach flat-top until after 1.0 s
Sep 2 1999 02:42:40:483PM	990902016	Spencer Pitcher	repeat, but.. change density demand to flat-top earlier
Sep 2 1999 03:05:36:217PM	990902017	Spencer Pitcher	repeat, flappers open
Sep 2 1999 03:13:00:920PM	990902018	Spencer Pitcher	repeat, flappers open, move gas puff to AB lim
Sep 2 1999 03:45:22:107PM	990902019	Spencer Pitcher	repeat, flappers closed, no N2 puff no plasma
Sep 2 1999 03:45:38:187PM	990902020	Spencer Pitcher	no plasma
Sep 2 1999 04:39:06:810PM	990902021	Spencer Pitcher	plasma, "high" density NL_04= 1.76e20 at 1 s, no N2 puff. This serves as the background shot for the "high"density shots 15-18
Sep 2 1999 04:42:41:327PM	990902022	Spencer Pitcher	plasma, lower density NL_04=0.7e20, N2 puff thru B31-038 (outer divertor) flapper closed
Sep 2 1999 04:42:18:763PM	990902023	Spencer Pitcher	plasma, repeat, NL_04=0.75e20, N2 puff thru B31-038 (outer divertor) flapper open
Sep 2 1999 04:55:44:967PM	990902024	Spencer Pitcher	plasma, repeat, NL_04=0.84e20, N2 puff thru A-B Limiter flapper closed
Sep 2 1999 05:12:24:873PM	990902025	Spencer Pitcher	plasma, repeat, NL_04=0.9e20 at 0.85 s, N2 puff thru A-B Limiter flapper open

Physics Operator Comments
Sep 2 1999 07:13:56:623AM		Bill Rowan	Engineering setup for run 990902 MP#222. Impurity Compression and Enrichments Studies SL: Pitcher/Goetz PO: Rowan Run should begin at 9:00am and end at 5:00pm ICRF may piggyback as possible to continue conditioning. Engineering setup: ECDC overnight in D2. Turn off at 5:30 am. We will run 5.4 T shots at 1.0 MA in D2 and vary the density from 0.7e20 to 1.4e20. Lengthen shot from 1.4 to 1.5 s. Setup power supplies from 990901015. Gas setup - fill B-top with 6 psi of D2 Hybrid enabled fill B-side lower with 1 psi of N2 Hybrid DISABLED fill B-side upper with 6 psi of H2 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.
Sep 2 1999 07:16:09:733AM		Bill Rowan	ECDC ran overnight . It was started at 5:15pm and shut off at 4:49. (Report from Silva.)
Sep 2 1999 07:45:08:467AM		Bill Rowan	Started PCS at approx 7:30 Loaded shot 990902015 on request of SL Cold start at approx 7:40 with expected response rtnode -- data loaded, A matrix responds rtnode -- data loaded, M matrix responds rtnode -- data loaded, PID matrix responds RT_NODE Done
Sep 2 1999 08:17:39:060AM		Bill Rowan	Irby reports that ECDC ran for 6 minutes. This is based on RGA log of pressure in vacuum vessel..
Sep 2 1999 09:06:02:857AM	990902001	Bill Rowan	Shot 001 Changed the NL_04 request to 1.0 at request of SL (ref run plan) Load/Clean: Load at 2-Sep-1999 08:03:23.00
Sep 2 1999 09:30:58:560AM	990902001	Bill Rowan	plasma. 1 MA. NL_04 is approx 1e20. Slight ramp after 1 s
Sep 2 1999 09:52:27:107AM	990902002	Bill Rowan	Shot 002 No changes. Plasma
Sep 2 1999 10:04:34:013AM	990902003	Bill Rowan	Shot 003 Extended shot length to 1.5 s Clean load: Load at 2-Sep-1999 09:57:43.00
Sep 2 1999 10:11:05:903AM	990902003	Bill Rowan	Plasma
Sep 2 1999 10:29:07:077AM	990902004	Bill Rowan	Shot 004 No changes. Plasma
Sep 2 1999 10:36:01:280AM	990902005	Bill Rowan	Shot 005 No changes
Sep 2 1999 11:01:01:327AM	990902005	Bill Rowan	Plasma
Sep 2 1999 11:01:31:000AM	990902006	Bill Rowan	Shot 006 Cell access before this shot
Sep 2 1999 11:16:50:623AM	990902006	Bill Rowan	Plasma
Sep 2 1999 11:36:19:733AM	990902007	Bill Rowan	Shot 007 No changes for this shot. Plasma.
Sep 2 1999 11:49:28:437AM	990902008	Bill Rowan	No changes. Plasma
Sep 2 1999 12:22:46:390PM	990902009	Bill Rowan	Shot 009 Plasma. No changes.
Sep 2 1999 12:44:09:577PM	990902010	Bill Rowan	Shot 010 Plasma. No changes.
Sep 2 1999 01:08:00:857PM	990902012	Bill Rowan	Shot 011 Fizzle No changes for next shot
Sep 2 1999 01:15:37:500PM	990902012	Bill Rowan	Shot 012 Plasma
Sep 2 1999 01:26:31:780PM	990902013	Bill Rowan	Shot 013 No changes. Plasma
Sep 2 1999 02:07:21:780PM	990902015	Bill Rowan	Shot 015 Increased density to 1.8e20
Sep 2 1999 02:21:08:763PM	990902015	Bill Rowan	Plasma
Sep 2 1999 02:21:33:590PM	990902016	Bill Rowan	Shot 016 Increased density ramp rate
Sep 2 1999 02:49:28:013PM	990902016	Bill Rowan	Plasma
Sep 2 1999 02:55:11:340PM	990902017	Bill Rowan	Shot 017 No change for this shot Plasma
Sep 2 1999 03:11:02:030PM	990902018	Bill Rowan	Shot 018 No change for this shot Plasma
Sep 2 1999 03:32:30:903PM	990902019	Bill Rowan	Shot 019 No change for this shot No plasma. No TF
Sep 2 1999 03:51:19:217PM	990902020	Bill Rowan	Shot 20 No change for this shot Fizzle
Sep 2 1999 03:58:14:733PM	990902021	Bill Rowan	Shot 21 Reduced IC_EF4 by 15A before t=0 Plasma
Sep 2 1999 03:59:37:200PM	990902022	Bill Rowan	Shot 22 Decreased request for NL_04 to 0.7e20
Sep 2 1999 04:15:22:967PM	990902022	Bill Rowan	Shot 22 Decreased request for NL_04 to 0.7e20 Plasma. Density slightly high.
Sep 2 1999 04:33:59:467PM	990902023	Bill Rowan	Shot 23 No chages for this shot. Plasma
Sep 2 1999 04:53:13:700PM	990902024	Bill Rowan	Shot 24 No changes for this shot. Plasma
Sep 2 1999 05:11:05:030PM	990902025	Bill Rowan	Shot 25 No changes for this shot. Plasma

Engineering Operator Comments
Shot	Time	Type	Status	Comment
1	09:26:29:390AM	Plasma	Ok	no faults/plasma 09:26 start
2	09:49:01:467AM	Plasma	Ok	no faults
3	10:07:48:950AM	Plasma	Ok	no faults/plasma
4	10:25:27:030AM	Plasma	Ok	no faults/plasma
5	10:44:18:513AM	Plasma	Ok	no faults/plasma
6	11:08:48:090AM	Plasma	Ok	no faults/plasma
7	11:26:50:437AM	Plasma	Ok	no faults/plasma
8	11:47:10:780AM	Plasma	Ok	no faults/plasma
9	12:15:13:920PM	Plasma	Ok	no faults/plasma
10	12:32:12:107PM	Plasma	Ok	no faults/plasma
11	12:50:51:327PM	Plasma	Ok	no faults/fizzel
12	01:07:54:640PM	Plasma	Ok	no faults
13	01:24:48:700PM	Plasma	Ok	no faults
14	01:48:14:153PM	Plasma	Ok	no faults/dis
15	02:12:10:047PM	Plasma	Ok	no faults/plasma
16	02:30:01:140PM	Plasma	Ok	(null)
17	02:49:45:420PM	Plasma	Ok	(null)
18	03:07:56:107PM	Plasma	Ok	(null)
19	03:28:00:890PM	Plasma	Ok	(null)
20	03:40:58:340PM	Plasma	Ok	(null)
21	03:54:15:123PM	Plasma	Ok	(null)
22	04:11:47:090PM	Plasma	Ok	(null)
23	04:30:34:997PM	Plasma	Ok	(null)
24	04:50:40:840PM	Plasma	Ok	(null)
25	05:09:21:013PM	Plasma	Ok	(null)