| Miniproposals | ||||||||||
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| Operators | |
| Session leader(s): | Greg Wallace |
| Physics operator(s): | Robert Granetz |
| Engineering operator(s): | Andy Pfeiffer |
| Engineering Operator Run Comment |
| MP612 - Expanded exploration of LHCD density limit Session leader: G. Wa |
| Session Leader Plans |
| Entered: Aug 30 2010 01:38:18:800PM |
| Author: Greg Wallace |
| Session Leader Plan for 1100901
MP612 - Expanded exploration of LHCD Density Limit Session Leader: G. Wallace Physics Operator: R. Granetz Assistant PO: A. White Starting shot: Load 1100727018 (Upper null, 5.4 T, 800 kA). Reprogram nl_04 to be steady at 7.5e19 during flattop. Cryopump required for density control in USN and DN. LH setup: Launcher 0.1 mm behind LH limiter, 90 deg phasing (n|| = 1.9), 0.8-1.3 s on time. 1) Adjust launcher position and outer gap to get reliable operation at LH power of ~600 kW. (2-4 shots) 2) Scan inner gap (while keeping outer gap ~constant) between 0.9 and 1.3 s. Start from nominal inner gap of ~1.5 cm and decrease to ~-0.5 cm (i.e. fully limited) by end of LH pulse. (3-6 shots) 3) Repeat 1 & 2 in double null. Start with equilibrium from 1100820008 and adjust inner gap from ~1.5 cm to ~-0.5 cm during LH. Set nl_04 to steady 7.5e19 during flattop. (3-6 shots) 4) Repeat 2 & 3 at nl_04=4e19. (6-12 shots) 5) Try to get steady high density double null discharge without going into H-mode. Load shot 1100820029. Seed with Ar to keep plasma in L-mode. (2-4 shots) 6) If time allows, try experimenting with the 4-2-4-2-4 powered/unpowered columns approach to look at reflection coefficient pattern. |
| Physics Operators Plans |
| Entered: Aug 31 2010 06:11:58:913PM |
| Author: Anne White |
| Physics Operator Plan for 1100901
Engineering setup for Wednesday 2010/09/01 MP612 - Expanded exploration of LHCD density limit Session leader: G. Wallace Assistant Physics Operator: A. White Physics Operator: R. Granetz Overnight: standard ECDC and 60 C bake. Run will start at 09:00 and end at 17:00. Power systems as on 1100727018 (Ip=0.8 MA, 5.4 T, 0.7e20 m-2 (target), USN) A-coil configuration: +Dtop -Dbot -Jtop +Jbot; Hybrid enabled (standard configuration) Gas Setup: fill B-Top with 6 psi D2 Hybrid enabled (PG4) fill B-side lower with 1 psi Ar Hybrid enabled (PG1) leave B-side upper as is Hybrid DISABLED (PG2) fill B-main (C-side) with 40 psi D2 Hybrid enabled (PG3) DISABLE NINJA Enable the following gate valves and shutters, assuming no vacuum problems: ECE, VUV, Z-bolo, HIREX-Sr, B-spectrometer GV Torvac setup: keep gate valves open during pulse Specific diagnostics: DNB, MSE, scanning probes ------------------------------------------------------------------------------ Boronization: no overnight; no between-shot Impurity injector: no ICRF: no LH: yes DNB: yes Cryopump: yes ------------------------------------------------------------------------------ Run plan: setup shot in /home/whitea/pcs_scratch/1100901000 Start with an UN shape for first part of experiment 1) Perform outer gap scan shot to shot. 2) Perform an inner gap scan (ramp) during the LH pulse. Change to a DN shape. 3) Repeat 1) and 2) in DN. Perform outer gap scan shot to shot. Then perform an inner gap scan (ramp) during the LH pulse. 4) Repeat 2) and 3) (i.e. gap scans in UN and DN) now with lower density 5) Try for a high density DN shot, staying in L-mode. Ar seeding. 6) Stay with a density and shape per SL request if they change LH column power on/off. Different segments in DPCS are being used to switch between the two different equilibria, UN and DN. segment 1P: cryopump startup loaded from 1100827030 segment 2: 0.8 MA, Upper Null, based on reference shot 1100727018 (UN, 5.4 T, 0.8 MA). Changes: 1) nl_04 set to 7.5e19 during flat top. segment 3: 0.8 MA, Double Null, based on reference shot 1100820008 Changes: 1) ZCUR reprogrammed to give DN shape from t=0.5-1.4 sec. 2) nl_04 set to 7.5e19 during flat top. 3) wires 9-12 set to ref "10" segment 4: 0.8 MA, Double Null. Same as segment 2. Will change during run for density scan per session leader request. ************************************************************************** *NOTES* Ip flattop in segment 2 from t = 0.45 to 1.5 sec. Ip flattop in segment 3&4 from t = 0.35 to 1.56 sec. IC_EF4U in segment 2 is steady +2000 starting at t=0.4 sec. IC_EF4U in segment 3&4 is -66 at t=0.1, ramp to 0 at t=2.1 sec. nl_04 gain settings are very different from seg 2 to seg 3&4, i.e. different for the UN and DN reference shots used. Need to ask SL before start if he wants Ip flattop timing to be identical for the UN and DN parts of his run plan. Different EF4 currents are likely needed for making the different equilibria, but will double check this with Bob. Also, need to check if different nl_04 gains are standard for UN vs DN with cryo or if this is a special SL request, since he wants good ne control for LHCD density limit study. |
| Session Leader Summaries |
| Entered: Sep 2 2010 07:32:13:423AM |
| Author: Bill Rowan |
| Summary of beam into gas for calibration of CXRS and MSE viewing chords.
This is summary of an experiment that was conducted after the main run for the day was completed. It includes shots 1100901029-040. The angles between CXRS and MSE view-chords and the trajectory of the DNB were measured in beam into gas experiments to check the spatial calibration for each diagnostic. The DNB was fired into the C-Mod vacuum vessel which was backfilled with deuterium to an approximate pressure of 2 mT. The beam emission spectra were acquired for selected view-chords of the CXRS and MSE diagnostics with a high throughput, moderately high resolution spectrometer. The Doppler shifted beam emission will be used with measurement of the beam energy to determine the angle between the view chord and the beam. This will be compared with the in-vessel spatial calibrations made before the campaign began. Data was acquired for 3 MSE chords, 2 poloidal chords for the WideView CXRS and 3 toroidal chords for WideView CXRS. For most of the data, the angle between chord and beam was sufficiently large for the main energy component to be distinct from the remainder of the emission spectrum. This will assure simple analysis. After the experiment began, it became quite clear that there was adequate emission for a narrower slit to have been used. This would have improved the resolution and simplified the analysis. The data that was acquired is adequate for our purposes. |
| Entered: Sep 7 2010 10:26:48:900AM |
| Author: Greg Wallace |
| Session Leader Summary for 1100901
MP612 - Expanded exploration of LHCD Density Limit Session Leader: G. Wallace Physics Operator: R. Granetz Assistant PO: A. White The key goal of today was to investigate the role of the inner gap in the LHCD density limit on C-Mod. The run plan called for sweeping the inner gap to zero in USN and DN target plasmas. The USN data points were easy to get, but H-modes in the DN points caused difficulty in getting the data we were intersted in. Consequently we focused our efforts on the USN data points. A threshold of ~4mm was found for the inner gap, below which the non-thermal ECE increased significantly. HXR data has not been processed and the SL_SUMMARY will be updated once it is. Shots 1-12 have no HXR data. Shot 15 has no Thomson Scattering data. Interestingly, the change in plasma rotation with LH was in the co-current direction today, as compared to USN plasmas from the 08 run campaign which are in the opposite direction. LSN plasmas from the 10 campaign are also in the counter-current direction. Very perplexing.... List of good shots (all at 5.4 T, 800 kA, n|| = 1.9): 17: 550 kW, nl_04=7.2-7.9e19, nebar=1.3-1.35e20, upper null to limited sweep 20: 550 kW, nl_04=7-7.8e19, nebar=1.4-1.38e20, upper null, inner gap = 0.25-0.23 cm, scanning probe data taken 21: 550 kW, nl_04=6.9-7.4e19, nebar=1.25-1.3e20, upper null, inner gap = 0.4-0.5 cm, scanning probe data taken 25: 550 kW, nl_04=7.2-7.8e19, nebar=1.3-1.4e20, limited to upper null sweep, scanning probe data taken 26: 650 kW, nl_04=7-7.5e19, nebar=1.25-1.35e20, upper null, inner gap = 0.4-0.5 cm, scanning probe data taken 28: 750 kW, nl_04=7-7.5e19, nebar=1.25-1.35e20, upper null, gap = 0.45 cm |
| Physics Operator Summaries |
| Entered: Sep 1 2010 05:27:56:630PM |
| Author: Anne White |
| Run 1100901 Phys Ops Summary
Overall this was a successful run for LH. They were able to obtain good data with their scan of the inner gap and also good data at fixed gap. For shots 1 and 2 today we encountered fizzles that were caused by poor early density control. This was tracked to a problem with the cryopump. This problem was diagnosed by looking at the G side pressure and noting that it was too high early on ( t < 0) . G side pressure too high (0.12) should be 0.04-0.08 and ratiomatic shows late increase t= -0.4 with high values (2.5e-5 at t=-0.2). Also, the pressure in the vesssel (IGT Chamber on big screen...) was oscillating before a shot ranging from 1e-8 up to 1e-6. The cryopump valves were manually toggled, and this helped with the problem. The other three fizzles (shots 07, 11, 19) seemed to be caused by bounces early in the discharge, based on a double peak in the tang Z meter and h-alpha traces and by inspection of the ece signals on the bounce scope. We did not do anything to alter the startup to correct these, and we encountered no sequential fizzles. DNB ran well on most shots, but check Granetz summary for details on a few shots where it was unavailable. Several shots had large injections, but could not be traced to LH or other direct causes. Density control was reasonably good, but in places more discharge development could help improve it further. When we tried to run DN, we got into H-mode so did not run many shots with this shape, only 13 and 14 were DN. The inner gap scans going from gaps of 1.5 or 1.0 cm to wall limited worked out well and provided information on what value of fixed gap (4mm) to run with. Shot 21 and repeats of 21 are good examples of fixed gap demands. Shot 12 and shot 15 are good examples of the inner gap scan demands. When we reversed the inner gap scan on shots 22-25, where we went from inner wall limited to a gap of roughly 1 cm, it was observed that the attempts to keep the plasma off the inner wall before the scan began cuased a large bounce in CLEARIN around t = 0.4 sec. An attempt to stop this made it worse. It was determined that this early bounce in the plasma did not affect the later LH experiment, so we did not try to fix this. ***************** Caveat Loader **************************** Some notes of interest if one wants to reload these shots: When we ran USN, segment 2 is the active segment. When we ran DN (only shots 13 and 14), segment 3 was the active segment. The title of segment 1 is "2010 cryopump startup" on this day from shot 3 onward but this is misleading!! We actually ran with a pre-fill gas pulse on PULSE_GAS4 of only 40 ms from shot 3 onward. We had made this change from the standard 50 ms because of the cyropump problems early on, but we ended up keeping this all day long because it worked. |
| Session Leader Comments | |||
| Jan 25 2011 02:34:11:437PM | 1100901001 | Greg Wallace | Fizzle. |
| Jan 25 2011 02:34:15:707PM | 1100901002 | Greg Wallace | Fizzle. |
| Jan 25 2011 02:34:29:790PM | 1100901003 | Greg Wallace | Good shot! Steady LH 400 kW net, 90 deg (n||=1.9), 100 kW/klystron. nl_04~6e19 on this shot---a bit lower than I wanted. Will try for more power (150 kW/klystron) and higher density (nl_04~7.5e19) on next shot. |
| Jan 25 2011 02:34:42:130PM | 1100901004 | Greg Wallace | Many LH trips during second half of shot. LH seems to be causing a big increase in density. Looks like some glowing on launcher based on WIDE2 camera view. Will pull launcher back slightly for next shot. |
| Jan 25 2011 02:34:52:463PM | 1100901005 | Greg Wallace | Good shot! 600 kW steady LH power (150 kW/klystron), 90 deg (n||=1.9). nl_04 = 7-7.5e19 during LH. Next shot will try for inner gap scan in upper null, same LH. |
| Jan 25 2011 02:35:09:470PM | 1100901006 | Greg Wallace | Good shot! LH ran clean at 600 kW, 90 deg (n||=1.9). Left gap decreases from 1.4 cm to 0 cm between 0.9 s and 1.3 s. nl_04 varying from 7-7.9e19 during sweep. ECE does not show an increase in nonthermal emission as we approach limited configuration. For the next shot we'll try to get sweep to limited plasma to end a little earlier and try to get density to stay steady after 1.2 s. |
| Jan 25 2011 02:35:19:173PM | 1100901007 | Greg Wallace | Fizzle. |
| Jan 25 2011 02:35:29:927PM | 1100901008 | Greg Wallace | OK shot. One LH trip late in the pulse. Slight rise in nonthermal ECE as plasma goes towards zero left gap despite small increase in density. 600 kW LH at 90 deg (n||=1.9). nl_04=7.5-8e19 during LH. Change in plasma rotation is in co-current direction!??!? Next shot will try to keep outer gap constant and keep density constant. |
| Jan 25 2011 02:35:42:957PM | 1100901009 | Greg Wallace | More trips late in the shot. Looks like something funny on col 13? Faults showing up on klystrons 5 and 10. Can't see any real flashing on the WIDE2 camera but there are some hot spots. Will try going back to the RCUR programming from shot 8 to see if this helps fix the problem. |
| Jan 25 2011 02:35:53:630PM | 1100901010 | Greg Wallace | Good shot! One LH trip but got what we wanted with the inner gap scan and constant density. 600 kW net LH power, 90 deg (n||=1.9). nl_04=~7.6e19 and fairly steady. Some increase in nonthermal ECE as we approach zero inner gap. Increasing the outer gap seems to help LH run cleaner. Will try one more time for this condition. |
| Jan 25 2011 02:36:02:300PM | 1100901011 | Greg Wallace | Fizzle. |
| Jan 25 2011 02:36:12:090PM | 1100901012 | Greg Wallace | Good shot!! LH ran clean through th epulse at 600 kW, 90 deg (n||=1.9). nl_04 steady at 7.5-7.7e19 during LH. Nonthermal ECE starts to increase around 1.16 s, corresponding to an inner gap of ~4.5 mm. This is exactly what we need for step 2 of the run plan. Moving on to step 3 of run plan: double null inner gap scan. |
| Jan 25 2011 02:36:24:080PM | 1100901013 | Greg Wallace | Many LH trips. Looks like flashing on the grill. Outer gap is already pretty big (1.5-2.4 cm) so we'll try pulling the launcher back a little on next shot. Also, density is too high. Will reduce nl_04 demand to 7.5e19 on next shot. |
| Jan 25 2011 02:36:33:660PM | 1100901014 | Greg Wallace | Double null attempt #2. LH had one trip, looks like something on the plasma side but don't see anything on the WIDE2 view. Two ELM-free H-modes in the double null, not much nonthermal ECE except when the density drops back down. Next shot will go back to try to repeat shot 12 from before. Need to get that data point with HXR. |
| Jan 25 2011 02:36:43:700PM | 1100901015 | Greg Wallace | Good shot!! Got HXR data and the shot we wanted. Again, the threshold for the rise in nonthermal ECE is around 4.5 mm inner gap. nl_04 = 7.4-7.8e19, PLH=550 kW, 90 deg (n||=1.9). Thomson scattering data is missing on this shot. Next shot will be the same as this except we'll only scan the inner gap from 7.5 mm to 0 mm. |
| Jan 25 2011 02:37:06:403PM | 1100901016 | Greg Wallace | Good shot! 550 kW net, 90 deg. Density rises as inner gap decreases---will try to get more steady density on next shot by dropping programmed nl_04 to 7.5e19 starting at 1.05 s. LH will repeat. |
| Jan 25 2011 02:37:19:930PM | 1100901017 | Greg Wallace | Good shot!! 550 kW, 90 deg, nl_04=7.2-7.4e19. Looks like threshold is about 3-4 mm on this shot. Next shot will try to keep a constant inner gap of about 3mm. |
| Jan 25 2011 02:37:38:680PM | 1100901018 | Greg Wallace | Good shot! 2mm inner gap on this shot. nl_04=8-7e19, 550 kW, 90 deg. Next shot will try for 4 mm constant inner gap. |
| Jan 25 2011 02:37:48:623PM | 1100901019 | Greg Wallace | Fizzle. |
| Jan 25 2011 02:37:57:837PM | 1100901020 | Greg Wallace | Good shot! Net LH power = 550 kW, 90 deg, nl_04 = 7.7-7.0e19. Upper null with inner gap around 2.5-3 mm. Will try again with a inner gap ~2mm larger than this shot. Will also make nl_04 program steady at 8e19. |
| Jan 25 2011 02:38:07:477PM | 1100901021 | Greg Wallace | Good shot! Upper null, outer gap 4-4.5 mm. Net LH power 550 kW, 90 deg, nl_04= 7.4-6.9e19 during LH. HXR looks good.
Next shot will sweep from inner wall limited plasma to upper null during LH. |
| Jan 25 2011 02:38:17:863PM | 1100901022 | Greg Wallace | OK shot. Got the scan in inner gap we wanted (limited==>upper null) but density was decreasing rapidly during the scan. LH rean clean. Next shot will attempt to get steady density of ~7.5e19 on nl_04. |
| Jan 25 2011 02:38:32:390PM | 1100901023 | Greg Wallace | Pretty good shot. Clean LH at 550 kW, 90 deg, nl_04=6.5-7.5e19. ECE peaks at 1.05 s, corresponding to 4 mm inner gap. ECE is still strongly tied to density, though. Will try again to get density more steady during the shot. |
| Jan 25 2011 02:38:42:183PM | 1100901024 | Greg Wallace | Density control is better, but still not quite flat. Clean LH at 575 kW, 90 deg, nl_04=7.5-7e19. Will repeat with (hopefully) totally flat density during LH. |
| Jan 25 2011 02:38:55:017PM | 1100901025 | Greg Wallace | Good shot! Density still moving around slightly but we're moving on. 550 kW net LH power, 90 deg, nl_04=7.25-7.75e19. Next shot will be a repeat of shot 21 but with LH power set to 180 kW/klystron. |
| Jan 25 2011 02:39:04:927PM | 1100901026 | Greg Wallace | Good shot! at 650 kW net, 90 deg, nl_04=7-7.5e19. Inner gap steady around 4 mm. More power! Going to 200 kW/klystron. |
| Jan 25 2011 02:39:15:333PM | 1100901027 | Greg Wallace | Shot looks OK until 1.1 s when an injection causes the X-rays to take off big time. Next shot will repeat. |
| Jan 25 2011 02:39:25:863PM | 1100901028 | Greg Wallace | Good shot!! Clean LH at 750 kW net LH power, 90 deg, nl_04=7-7.5e19. Probably some current drive based on loop voltage changes. Will have to see about MSE.
Last shot of the day. |
| Physics Operator Comments | |||
| Sep 1 2010 09:25:23:577AM | 1100901001 | Anne White | First shot
USN, 0.8 MA, 5.4 T reference shot 1100727018 Changes from reference shot: Ip flattop extended to t = 0.35 to 1.56 sec. Bt flattop to 1.57 sec nl_04 set to steady 7.5e19 m-3 engineering settings: TF current down to 165 kA from 175 kA Fizzle detector off time extended to 2.1 sec from 1.8 sec. Result: fizzle G side pressure too high (0.12) should be 0.04-0.08 ratiomatic shows late increase t= -0.4 with high values (2.5e-5 at t=-0.2) cryo may have failed. will retry shot, no changes |
| Sep 1 2010 09:35:25:233AM | 1100901002 | Anne White | No changes from last shot.
result: fizzle Gside pressure is again too high, 0.13 mtorr Checked all Vs screen, no other gas in on early except for 50 ms Pulse Gas 4 Cell access to check cryo pump valves. all seems well. valve was toggled by hand. ninja in not on. do notice that vessel pressure is fluctuating before shot ranging from low 2e-7 Torr up to 3e-6 Changes for next shot: For next shot we reduced the pulse gas4 to a 40 ms pulse (reduced from 50ms) As we expect cryo to not work as it should. |
| Sep 1 2010 10:05:27:450AM | 1100901003 | Anne White | Changes from last shot:
For this shot we reduced the pulse gas4 to a 40 ms pulse (reduced from 50ms on shot 2) As we suspect cryo is not working as it should. Result: shot ran. good breakdown. Gside pressure 0.05, note that chamber pressure before shot was in 1e-8 Torr range before this shot. Plan for next shot: keep 40 ms prefill for now. density is low, only 6e19, compared to 7.5e19 request. but steady line avg. will increase nl_04 demand to 9e19, keep gains the same |
| Sep 1 2010 10:18:24:150AM | 1100901004 | Anne White | Changes from last shot:
keep 40 ms prefill for now. density is low, only 6e19, compared to 7.5e19 demand, but steady line avg. will increase nl_04 demand to 9e19, keep gains the same Result: shot ran. decent breakdown. gside pressure around 0.1 at t= 0 sec. note that chamber pressure before shot went up into 1e-6 torr range. also, got notice that cryo failed on that shot right before we took shot. cell access after shot to check the cryo. on density control, got closer to 7.5e19 with the higher demand, and we had good ne control until around t = 0.9 seconds, when density shot up. core Te dropped. no drop in Halpha, not an H-mode? but could be injections of some sort near 1 sec. Plans for next shot: no changes. |
| Sep 1 2010 10:39:01:077AM | 1100901005 | Anne White | Changes from last shot:
no changes. Result: shot ran. chamber pressure looks good before shot, 1e-7 torr range in check stage. got news that cryo looked good. SL says density control is fine. Plans for next shot: loaded the CLEARIN and RCUR ramps from shot 888, segment 2 in /home/whitea/pcs_scratch These ramps should give an inner gap scan from 1.5 cm to -0.5 cm from t = 0.9 to 1.3 seconds, while keeping outer gap the same. per session leader request also, moved the time when inner gap gets set to 1.5 cm to an earlier time, from t ~ 0.45 to t ~ 0.35. |
| Sep 1 2010 10:48:17:850AM | 1100901006 | Anne White | Changes from last shot:
loaded the CLEARIN and RCUR ramps from shot 888, segment 2 in /home/whitea/pcs_scratch These ramps should give an inner gap scan from 1.5 cm to -0.5 cm from t = 0.9 to 1.3 seconds, while keeping outer gap the same. per session leader request also, moved the time when inner gap gets set to 1.5 cm to an earlier time, from t ~ 0.45 to t ~ 0.35. Result: Shot ran Plans for next shot: make inner gap ramp faster, bring to -0.5 earlier, at t= 1.25 sec. also, SL requests we reduce nl_04 demand from 9e19 to 8e19 at t = 1.2 seconds. |
| Sep 1 2010 05:17:19:230PM | 1100901007 | Anne White | Changes from last shot:
made inner gap ramp faster, bring to -0.5 earlier, now at t= 1.25 sec instead of 1.3 sec on shot 6. also, reduced nl_04 demand from 9e19 to 8e19 at t = 1.2 seconds. Result: fizzle at first the uptick in tang z meter and halpha on init scope around t = 0.015 sec seemed to indicate a bounce, but early ece signals don't seem to show this and Bob G. also does not think there was a bounce, thinks it may have been an injection. The early pressure and fields, Br Bz, looked okay as well. (update : Steve Wolfe. thinks it may have been a bounce, seen on ece early. One could have increased prefill to remedy, but we did nothing and the next shot ran fine.) Plans for next shot: no changes. |
| Sep 1 2010 11:27:53:403AM | 1100901008 | Anne White | Changes from last shot:
no changes. Result: shot ran. but outergap is still increasing after t = 1 sec. Plans for next shot: to compensate for outer gap evolving, we will keep the linear ramp down in RCUR, but at t = 1.25 seconds we have increased RCUR by 0.35 cm (since gap was changing by about 0.7 cm in time of interest) also reduce the demand on nl_04 from 8e19 to 7.5e19 late in time. and move the time that the demand changes earlier to 1.15 sec instead of 1.2 sec. |
| Sep 1 2010 11:31:55:630AM | 1100901009 | Anne White | Changes from last shot:
to compensate for outer gap evolving, we kept the linear ramp down in RCUR, but at t = 1.25 seconds we have increased RCUR by 0.35 cm (since gap was changing by about 0.7 cm in time of interest) last shot 008 RCUR = 0.648650, t = 1.25 sec this shot 009 RCUR = 0.652150, t = 1.25 sec also reduced the demand on nl_04 from 8e19 to 7.5e19 late in time. and move the time that the demand changes earlier to 1.15 sec instead of 1.2 sec. Result: shot ran. density ok. Plans for next shot: Go back to RCUR programming we had in shot 8, but keep the density demand same as shot 9. |
| Sep 1 2010 11:49:05:303AM | 1100901010 | Anne White | Changes from last shot:
Go back to RCUR programming we had in shot 8, but keep the density demand same as shot 9. Result: shot ran Plans for next shot: no changes |
| Sep 1 2010 12:17:51:617PM | 1100901011 | Anne White | Changes from last shot:
no changes Result: fizzle looks like a bounce. leave the prefill as is for now. if bounce again, we will increase prefill 10% Plans for next shot: no changes |
| Sep 1 2010 12:32:02:827PM | 1100901012 | Anne White | Changes from last shot:
no changes Result: shot ran. Plans for next shot: Change to the DN shape from reference shot 11100820008 active segment is segment 3 in dpcs now next shot will have the same RCUR, CLEARIN and NL_04 demands as on shot 012 Note that ZCUR demand is set for DN shape between t = 0.4 and 1.4 sec. |
| Sep 1 2010 12:51:26:313PM | 1100901013 | Anne White | Changes from last shot:
Changed to the DN shape from reference shot 11100820008 active segment is segment 3 in dpcs now next shot will have the same RCUR, CLEARIN and NL_04 demands as on shot 012 Note that ZCUR demand is set for DN shape between t = 0.4 and 1.4 sec. Result: shot ran. But there is a bounce during startup, but we recovered from that. EFIT does show DN. Inner wall limited time is coming at t =1.27 according to EFIT Density is a little to high Plans for next shot: Reduce demand for next shot to steady nl_04 = 7.5e19 Bring inner wall limited time earlier on RCUR and CLEARIN ramp. set to t = 1.2 sec, it was 1.25 sec. |
| Sep 1 2010 01:13:02:120PM | 1100901014 | Anne White | Changes from last shot:
Reduced density demand to steady nl_04 = 7.5e19 Brought inner wall limited time earlier on RCUR and CLEARIN ramp. set to t = 1.2 sec, it was 1.25 sec. Made no changes in startup to deal with bounce. but may need to later. Result: shot ran better breakdown, smoother, no bounce. Plans for next shot: Return to DPCS settings for shot 012. Shape back to USN. Keep segment 1 as in shot 014, now active segment will be segment 2 and segment 2 is the same as on shot 012. |
| Sep 1 2010 01:32:35:007PM | 1100901015 | Anne White | Changes from last shot:
Returned to DPCS settings for shot 012. Shape back to USN. Keep segment 1 as in shot 014, active segment is segment 2 and segment 2 is the same as on shot 012. Result: shot ran good USN LH shot. this time with HXR data. good repeat of shot 12. Plans for next shot: the inner gap scan should now start at 0.75 cm and go to -0.5 cm ramping from t = 0.9 to t = 1.25 sec. |
| Sep 1 2010 01:49:00:130PM | 1100901016 | Anne White | Changes from last shot:
the inner gap scan set to start at 0.75 cm and go to -0.5 cm ramping from t = 0.9 to t = 1.25 sec. for start of ramp: RCUR set to 0.6549 at t = 0.9 sec (it was 0.658650 on shot 15) CLEARIN set to -0.0032 at t = 0.9 sec (it was 0.0043 on shot 15) Result: shot ran inner gap scan ok. EFIT says about we scan from 0.9 to 0.0 cm outer gap increases about 4 mm in time of interest. density too high. Plans for next shot: reduce nl_04 demand to 8.5e19 until 1.05 sec, then reduce demand to 7.5e19 from 1.05 sec onward |
| Sep 1 2010 02:05:17:520PM | 1100901017 | Anne White | Changes from last shot:
reduced nl_04 demand to 8.5e19 until 1.05 sec, then reduce demand to 7.5e19 from 1.05 sec onward Result: shot ran Plans for next shot: Try to make inner gap of 4 mm Did this by setting RCUR and CLEARIN to steady values during shot. The values chosen were the RCUR and CLEARIN values from shot 017 at t = 1.2 sec. |
| Sep 1 2010 02:38:29:887PM | 1100901018 | Anne White | Changes from last shot:
Try to make inner gap of 4 mm Did this by setting RCUR and CLEARIN to steady values during shot. The values chosen were the RCUR and CLEARIN values from shot 017 at t = 1.2 sec. Result: shot ran bounce in startup, but recovered EFIT says inner gap 2 mm Plans for next shot: Increase inner gap by 2 mm but keep outer gap the same. CLEARIN increased to -0.012 from -0.014, and RCUR increased from 0.649507 to 0.650507. density is decreasing in time, but leave nl_04 alone. |
| Sep 1 2010 02:32:30:880PM | 1100901019 | Anne White | Changes from last shot:
Increase inner gap by 2 mm but keep outer gap the same. CLEARIN increased to -0.012 from -0.014, and RCUR increased from 0.649507 to 0.650507. Result: fizzle culprit looks to be a bounce, fields are okay. will run again. note that 018 also had bounce in startup but recovered. plan would be to increase prefill 10% to 44 ms from 40 ms if bounce/fizzle occurs again. Plans for next shot: no changes. |
| Sep 1 2010 03:15:45:523PM | 1100901020 | Anne White | Changes from last shot:
no changes. Result: shot ran clean breakdown. no bounce in startup. EFIT says inner gap between 0.25 and 0.3 cm in time of interest for LH, t = 0.9-1.3 sec, and density decreases during this time from 7.75e19 to 7e19 Plans for next shot: increase inner gap by 2mm. Increase CLEARIN to -0.010 from 0.012 Increase RCUR to 0.651507 from 0.650507 set density demand to be steady at 8e19 |
| Sep 1 2010 03:15:17:933PM | 1100901021 | Anne White | Changes from last shot:
atttempted to increase inner gap by 2mm. Increased CLEARIN to -0.010 from 0.012 Increased RCUR to 0.651507 from 0.650507 set density demand to be steady at 8e19 Result: shot ran. breakdown ok. no bounce in startup. Looks like we got the inner gap at 4.0-4.5 mm in LH pulse and kept density much more constant. Plans for next shot: Go back and repeat shot 17, but reverse the inner gap scan: from t = 0.9 to t = 1.25 seconds start from inner wall limited and increase gap to around 1 cm. |
| Sep 1 2010 03:27:16:470PM | 1100901022 | Anne White | Changes from last shot:
Go back and repeat shot 17, but reverse the inner gap scan: from t = 0.9 to t = 1.25 seconds start from inner wall limited and increase gap to around 1 cm. Result: shot ran breakdown ok, no bounce in startup Plans for next shot: keep RCUR and CLEARIN demands the same, but we will change density demand. nl_04 is at 7.5e19 steady until 1 sec then demand is increased to steady 8.5e19 |
| Sep 1 2010 03:49:15:233PM | 1100901023 | Anne White | Changes from last shot:
kept RCUR and CLEARIN demands the same, changed density demand. now nl_04 is at 7.5e19 steady until 1 sec then demand increases to steady 8.5e19 Result: shot ran shot 22 and 23 hadbig jumps in CLEARIN (about 1 cm) at t < 0.5 sec density control is not optimum on 23, it is decreasing after t = 0.92 sec Plans for next shot: CLEARIN and RCUR are changed later (t =0.45 sec) to give inner wall limited plasma. This was done to avoid changing CLEARIN and RCUR at the time t = 0.42 when OH1 passes through zero and we lose control Also set density demand for increase to 8.5e19 to start earlier at t = 0.9 sec |
| Sep 1 2010 04:00:25:603PM | 1100901024 | Anne White | Changes from last shot:
CLEARIN and RCUR are changed later (t =0.45 sec) to give inner wall limited plasma. This was done to avoid changing CLEARIN and RCUR at the time t = 0.42 when OH1 passes through zero and we lose control Also set density demand for increase to 8.5e19 to start earlier at t = 0.9 sec Result: shot ran. density still not as steady as we'd like after t = 1 sec the changes I made in CLEARIN and RCUR made bounce in CLEARIN around t =0.4 sec worse, which in hindsight makes sense since those changes meant we demanded an increased in gap at that time, so bigger bounce out. We could just run inner wall limited until the gap scan starts, but I was worried about the glowing tile corner on inner wall so I wanted to go into inner wall limited as late as possible. Plans for next shot: adjust nl_04 demands to increase density to 9e19 at t = 0.9 sec. |
| Sep 1 2010 04:16:45:470PM | 1100901025 | Anne White | Changes from last shot:
Adjusted nl_04 demand to 9e19 at t = 0.9 sec. Result: shot ran breakdown looked ok. still had CLEARIN bounce at t = 0.4-0.5 sec Plans for next shot: repeat shot 21 |
| Sep 1 2010 04:37:23:360PM | 1100901026 | Anne White | Changes from last shot:
changed to a repeat of shot 21 Result: shot ran good breakdown Plan for next shot: no changes, repeat |
| Sep 1 2010 04:54:43:277PM | 1100901027 | Anne White | Changes from last shot:
no changes, repeat Result: shot ran. looks like big injection near t = 1.2 seconds Plan for next shot: repeat |
| Sep 1 2010 06:46:27:643PM | 1100901028 | Anne White | Last shot of run for
MP612 - Expanded exploration of LHCD Density Limit Session Leader: G. Wallace Changes from last shot: no changes, repeat Result: shot ran. looked Last shot of the day. Thanks to everyone for helping out and making this a successful run! |
| Sep 1 2010 05:34:13:963PM | 1100901029 | Bill Rowan | Start of DNB-into-gas-filled-torus, no fields loaded shot 11001155016 turned off all power supplies set fizzle detector to past 2.0 sec this shot: gas only, no DNB RESULT: ratiomatic had been turned off, so we don't have a measurement of torus pressure. try again ... |
| Sep 1 2010 05:39:27:003PM | 1100901030 | Bill Rowan | Result: got desired pressure of 2.0 mTorr on F-side ratiomatic |
| Sep 1 2010 05:49:29:300PM | 1100901031 | Bill Rowan | Result: got correct pressure and two very nice DNB pulses. Good signal strength on spectrometer |
| Sep 1 2010 05:55:24:417PM | 1100901032 | Bill Rowan | Result: two good dnb pulses. second pulse has a little variation in current. ratiomatic: pressure = 2 mTorr. so this is a good shot |
| Sep 1 2010 06:03:59:833PM | 1100901033 | Bill Rowan | Put MSE spatial channel #1 (from R=73.6) into the UT spectrometer for this shot. Result: good dnb pulse and correct torus pressure. good shot. |
| Sep 1 2010 06:21:38:257PM | 1100901034 | Bill Rowan | MSE spatial channel S4 (R=81.7) into the UT spectrometer for this shot. Result: correct torus pressure. two good dnb pulses. good shot. Alas, the spectrometer did not acquire data. Must repeat this shot. |
| Sep 1 2010 06:45:30:957PM | 1100901035 | Bill Rowan | Repeat previous shot after a delay for computer issues. MSE spatial channel S4 into the UT spectrometer. good shot. spectrometer got data. So we can move on to the third MSE spatial channel on the next shot. |
| Sep 1 2010 06:52:03:010PM | 1100901036 | Bill Rowan | MSE spatial channel S1 (R=88.6) into UT spectrometer. got good DNB pulses. good shot. |
| Sep 1 2010 07:05:05:363PM | 1100901038 | Bill Rowan | Channel TF21 into spectrometer. good shot. |
| Sep 1 2010 07:11:39:440PM | 1100901039 | Bill Rowan | TF32 into spectrometer. Result: good. |
| Sep 1 2010 07:18:36:520PM | 1100901040 | Bill Rowan | TF33 into spectrometer. Result: good. ---- end of this beam-into-gas experiment |
| Engineering Operator Comments | ||||
| Shot | Time | Type | Status | Comment |
| 1 | 09:02:44:727AM | Plasma | Ok | |
| 2 | 09:16:49:150AM | Plasma | Ok | |
| 3 | 09:52:41:263AM | Plasma | Ok | |
| 4 | 10:06:25:980AM | Plasma | Ok | |
| 5 | 10:21:19:983AM | Plasma | Ok | |
| 6 | 10:37:01:680AM | Plasma | Ok | |
| 7 | 10:53:30:813AM | Plasma | Ok | |
| 8 | 11:06:53:500AM | Plasma | Ok | |
| 9 | 11:21:30:083AM | Plasma | Ok | |
| 10 | 11:41:42:403AM | Plasma | Ok | |
| 11 | 12:05:43:877PM | Plasma | Ok | |
| 12 | 12:18:49:897PM | Plasma | Ok | |
| 13 | 12:38:02:517PM | Plasma | Ok | |
| 14 | 12:58:10:650PM | Plasma | Ok | |
| 15 | 01:16:00:943PM | Plasma | Ok | |
| 16 | 01:32:42:090PM | Plasma | Ok | |
| 17 | 01:48:25:360PM | Plasma | Ok | |
| 18 | 02:06:33:487PM | Plasma | Ok | |
| 19 | 02:23:18:480PM | Plasma | Ok | |
| 20 | 02:38:07:097PM | Plasma | Ok | |
| 21 | 02:57:18:530PM | Plasma | Ok | |
| 22 | 03:17:00:420PM | Plasma | Ok | |
| 23 | 03:32:40:403PM | Plasma | Ok | |
| 24 | 03:49:23:993PM | Plasma | Ok | |
| 25 | 04:07:26:860PM | Plasma | Ok | |
| 26 | 04:25:04:290PM | Plasma | Ok | |
| 27 | 04:42:58:960PM | Plasma | Ok | |
| 28 | 05:00:41:803PM | Plasma | Ok | |
| 29 | 05:26:41:787PM | Test | Ok | DNB TESTS |
| 30 | 05:35:12:180PM | Test | Ok | DNB tests |
| 31 | 05:43:11:197PM | Test | Ok | |
| 32 | 05:52:06:220PM | Test | Ok | |
| 33 | 06:00:16:453PM | Test | Ok | |
| 34 | 06:10:10:617PM | Test | Ok | |
| 35 | 06:41:44:777PM | Test | Ok | |
| 36 | 06:48:27:160PM | Test | Ok | |
| 37 | 06:55:06:387PM | Test | Ok | |
| 38 | 07:01:57:603PM | Test | Ok | |
| 39 | 07:08:38:973PM | Test | Ok | |
| 40 | 07:15:22:710PM | Test | Ok | |
| System Availability | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
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