| Miniproposals | ||||||||||
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| Operators | |
| Session leader(s): | Jerry Hughes |
| Physics operator(s): | Jim Irby,Steve Wolfe |
| Engineering operator(s): | Andy Pfeiffer,Bill Parkin |
| Engineering Operator Run Comment |
| automatically entered by signon - please replace with real comment |
| Session Leader Plans |
| Entered: Aug 16 2007 01:05:01:187PM |
| Author: Jerry Hughes |
| MP506, run B: H-modes with cryopumping in USN, normal field direction
SL: Jerry Hughes PO: Jim Irby We will pick up this run where it left off on 1070808. This run is intended to complete the evaluation of pedestal and global H-mode response to cryopumping. It will be run in USN topology to maximize particle flux to the pumping slots. Requirements: **Diagnostics Edge and core Thomson, ECE diagnostics, CXRS, bolometer arrays, PCI, reflectometry, Hirex **Gas NINJA plenum loaded with 10psi D2 Argon puff: 50ms at 0.3s (Argon at 1psi) **ICRF at least 3MW available flat waveforms from 0.7 to 1.5s **cryopump cooled to He temp on first shot, and most thereafter Shot sequence: Proceed as follows until time runs out. 1. Reload 1070808001 (800kA, 5.4T, nl04=1e20). Pump COLD. Prf=3MW. 2. Lower target to nl04=8e19, pump COLD. Prf=3MW 3. Re-adjust target based on results of 1,2. Pump COLD. Prf=3MW 4. Lower Ip to 600kA, target nl04=8e19. Pump COLD. Prf=3MW 5. Lower target to nl04=6e19, pump COLD. Prf=3MW 6. Re-adjust target based on results of 4,5. Pump COLD. Prf=3MW 7. Choose a promising low-collisionality target from 1--6 and rerun with max. available Prf. Pump COLD. 8. Choose a suitable 800kA shot from 1--3 and rerun with pump WARM 9. Choose a suitable 600kA shot from 4--6 and rerun with pump WARM 10. Lower Ip to 400kA, nl04-->6e19. Prf=3MW. Pump COLD 11. Lower target to nl04=4e19, pump COLD 12. Re-adjust target based on results of 10,11. Pump COLD. Prf=3MW 13. Choose a suitable shot from 10--12 and rerun with pump WARM 14. Choose a low Ip, low density pumped target from above. Rerun with a current ramp up to 1MA from 1.1 to 1.5s, to see if low density H-mode can be maintained concurrent with Te,PED rise. |
| Physics Operators Plans |
| Entered: Aug 16 2007 09:02:16:127AM |
| Author: Jim Irby |
| Checklist before operation:
. 2200 V hi-pot of TF (complete: still open) . no power cycle test to verify ----- TF voltage tap scanner operation ----- proper operation of TF ground fault warning program . verify that TF is now gounded through 54M . verify that TF fault instrumentation is back in operation Operation: . 10 kA, 0.25 s TF test under PLC control (SOP following work on regulator) . 50 kA, 0.5 s TF test under PLC control (as on 1070814003) . 150 kA, 1.0 s TF test . 150 kA, 2.0 s TF test . Plasma operation 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) NINJA 10 psi deuterium, ENABLED |
| Entered: Aug 16 2007 04:54:34:963PM |
| Author: Steve Wolfe |
Engineering setup and Physop Plan for post-run beam-into-gas shots on Thursday, 16-Aug-2007 SL: Scott PO: wolfe (taking over from Irby) Engineering setup from 1070803032: NO POWER SYSTEMS Gas setup: Btop filled with D2 to 6psi (same as the plasma run) ENABLED All other valves disabled. NINJA disabled and off. Ratiomatic ON PCS: Load from 1070803032, verify seg1 on, segs 2-4 off. |
| Session Leader Summaries |
| Entered: Aug 17 2007 12:24:43:920PM |
| Author: Jerry Hughes |
| 1070816 Run Summary.
MP506, run B: H-modes with cryopumping in USN, normal field direction This run was intended to complete the evaluation of pedestal and global H-mode response to cryopumping. It was run in USN topology to maximize particle flux to the pumping slots. This run picked up where we left off on 1070808, before experimental operations were suspended to diagnose and ameliorate an intermediate TF ground fault condition. Plasma attempts began shortly after noon, and we were successful in making 15 discharges, all with ICRF heated H-modes. A range of currents (Ip=0.4, 0.6, 0.8MA) and target densities (nl04 from 0.6 to 1.0e20) were run, in an attempt to produce steady low-density H-mode regimes. Early discharges at 0.8MA showed promise, with relatively stationary H-modes lasting for several confinement times. Radiated power rose steadily in these H-modes, leading to an instability which rapidly cooled the pedestal and fueled the plasma, resulting in radiative collapse of the H-mode. Edge fluctuation measurements revealed quasi-coherent modes, though they were apparently insufficient to control impurity accumulation. The H-modes with the best confinement properties appeared to have classic grassy ELMs replacing the QCM, a regime we have not observed clearly in some time. ICRF performance was quite good, with routine net power of ~3MW. On shot 13 we attempted to couple 4MW and obtained a transient H-mode, followed by an extremely radiative L-mode. Performance was never really the same after this shot. For example, when we attempted to re-run shot 11 on shot 20, the rate-of-rise in radiated power was ~2x higher. Most of the late afternoon was spent trying to obtain steady H-modes at high q. On shot 24 a particularly low-density H-mode was maintained for 500ms at 400kA. We obtained only one direct comparison of a pumped and unpumped discharge: shots 20 and 22. Neutral pressure at the cryopump was several times higher in the unpumped case, and pedestal temperatures were lower. The indications are that the pump was working, and that an effect was had on the pedestals. We did, however, see little long-term pump-out of the H-mode discharges following their formation. This contrasts somewhat with the result in the reversed-field USN cases. Some careful analysis will be needed to figure out what all this means. |
| Physics Operator Summaries |
| Entered: Aug 17 2007 08:39:59:823AM |
| Author: Jim Irby |
| SL: Hughes
PO: Irby We began with tests of the TF magnet from 10 kA up to 150 kA. Before the run a 2200 V hi-pot of the magnet had been done and indicated the fault was either completely gone or at a high resistance. We carefully monitored ground fault, scanner, and real-time TF tap data and saw no indications of a fault. The M54 tap was being used as a ground for these tests and for the rest of the day during plasma operation. On shot 08 we made a very nice plasma (loaded from 1070808001) using the cryopump and with 1.8 MW of ICRF. We also had a 1.5A ground fault late in ramp-down. No other faults were detected the rest of the day. The machine ran extremely well during plasma operation. We had one cryopump dump induced fizzle and one dud caused by an inattentive Physop; the prefill pressure was allowed to drop too low. Changes around the bus tunnel seem to have added noise to the TF bus voltage signals. We need to investigate this problem on Monday. The cooling/warming cycles over the last few days improved the performance of the OH coaxes. Another issue we should investigate. tests 01,02,04,05,06,07 data 03 plasma 08,09,11,12,13,14,15,16,17,18 20,21,22,23,24 fizzle 10 dud 19 |
| Session Leader Comments | |||
| Aug 16 2007 01:24:52:130PM | 1070816008 | Jerry Hughes | USN, Ip=825kA, Bt=5.38T
Steady H-mode, with 1.6MW flat. Pedestal density rises after 1s, and plasma becomes more ELM-free. Pressure at pump rises to 4mtorr, at beginning of H-mode, then drops to 1mTorr. |
| Aug 16 2007 01:29:41:857PM | 1070816009 | Jerry Hughes | USN, Ip=825kA, Bt=5.39T
Steady H-mode, with more ICRF. Te,PED promptly jumps to >600eV. The same H-mode-killing behavior occurs at 1.16s --- i.e. radiation, pedestal cooling, enhanced pedestal fueling. Upper chamber and midplane pressure very similar to shot 8. |
| Aug 16 2007 01:59:08:930PM | 1070816012 | Jerry Hughes | USN, Ip=825kA, Bt=5.39T
early MARFE, 3 H-modes, each one colder than the previous. |
| Aug 16 2007 08:37:17:783PM | 1070816013 | Jerry Hughes | USN, Ip=825kA, Bt=5.39T
Impressive early H-mode, transient. Despite having 3.9MW steady, it stays in L-mode after 1s. Radiation is quite high. We are probably cooking limiters. |
| Aug 16 2007 02:33:13:397PM | 1070816014 | Jerry Hughes | USN, Ip=825kA, Bt=5.39T
target nl04 is closer to 1e20 on this shot. 5 ELM-free H-modes. Brian is questioning the efficacy of the pump, since they are operating it as a pot, and not flowing strongly. It is true that we're not seeing a lot of pump-out reflected in the starting densities of these multiple H-modes. |
| Aug 16 2007 02:57:57:110PM | 1070816015 | Jerry Hughes | USN, Ip=600kA, Bt=5.39T
nl04 target is 8e19 Cryopump will have strongly flowing He for this shot. Result: Transient H-modes. Lower density as expected. Reflectometry indicates QCM, but it seems to be insufficient to relieve impurity confinement. Brian indicates no difference in the pumping rate vs. not flowing strongly. However, he thinks the strike position should be moved out and more onto the pumping slots. |
| Aug 16 2007 03:10:49:813PM | 1070816016 | Jerry Hughes | USN, Ip=600kA, Bt=5.39T
nl04 target is 8e19 Strike point was moved out as requested, but it didn't affect the upper chamber pressure, and had no significant effect on the H-mode density. 4 transient H-modes. The first one has Te,PED>500eV. |
| Aug 16 2007 04:37:00:540PM | 1070816017 | Jerry Hughes | USN, Ip=600kA, Bt=5.39T
nl04 target is lowered 6e19 It is more ELM-free like. |
| Aug 16 2007 04:39:49:510PM | 1070816018 | Jerry Hughes | nl04-->1e20.
H-modes still transient. H-mode densities are not that different than with lower targets. |
| Aug 16 2007 04:00:21:840PM | 1070816019 | Jerry Hughes | No plasma |
| Aug 16 2007 04:10:30:930PM | 1070816020 | Jerry Hughes | An attempt to recover shot 011. ~800kA, nl04~8e19
Radiated power rise is ~2x higher than on shot 11. H-modes are transient, and are never able to reach the high Te,PED of earlier today. It seems we have definitely lost our lovely boronization. The QCM is there on reflectometry, but the impurites are still killing us. For next shot, back off ICRF demand to 2.5MW steady. |
| Aug 16 2007 04:19:30:050PM | 1070816021 | Jerry Hughes | Dropped ICRF program to 2.5MW. Results are similar. Several transient H-modes.
YAGs did not fire. |
| Aug 16 2007 04:56:24:170PM | 1070816022 | Jerry Hughes | This was a shot with the pump WARM to compare with shot 20. Upper chamber pressure
is several times higher. The H-modes appear to have colder pedestals. |
| Aug 16 2007 05:06:49:010PM | 1070816023 | Jerry Hughes | 400 kA. Very low density H-mode there. Repeat to improve RF matching. |
| Aug 16 2007 05:23:13:810PM | 1070816024 | Jerry Hughes | Long, low density H-mode. That's the last plasma shot. |
| Aug 16 2007 05:15:46:927PM | 1070816025 | Steve Scott | This shot starts a short (about 3 shot) series of DNB-into-torus shots with NO fields. Reference shot = 1070803032. about 3mTorr torus pressure in D2 Purpose: measure Doppler shift and thereby infer angle of MSE views result: DNB very similar to the reference shot 1070803032: peak current about 6.5, drooping down to about 3.9. gas pressure identical to reference shot. this is a fine member of the scan. next: repeat. |
| Aug 16 2007 05:24:57:970PM | 1070816026 | Steve Scott | DNB = idential to shot 25 gas = identical to shot 25 so this is another member of the scan |
| Aug 16 2007 05:38:12:390PM | 1070816027 | Steve Scott | DNB = terminated just a little earlier than previous shots gas = identical to shot 26 This is the last shot in the scan and the last shot cycle of the night. --------------------------------------------------------------------------------- |
| Physics Operator Comments | |||
| Aug 16 2007 09:05:50:800AM | 1070816001 | Jim Irby | No power cycle test
gf data looks good tf scanner data looks good (magnet about 1.4 mOhm) density feedback ready |
| Aug 16 2007 09:26:06:747AM | 1070816002 | Jim Irby | 10 kA TF test
no ground fault detected scanner looks good: 1.47 mOhm bus rogs look good got plenty of gas (PCS still loaded with beam into gas test) ground_fault routine ran properly: 2.407 A max current indicated in log |
| Aug 16 2007 09:38:13:200AM | 1070816003 | Jim Irby | no power test --- data system issues |
| Aug 16 2007 10:14:27:820AM | 1070816004 | Jim Irby | try for 50 kA test
loaded 1070808001 into PCS test looks good --- no increase in gf current |
| Aug 16 2007 10:24:28:050AM | 1070816005 | Jim Irby | 100 kA, 1s pulse
no ground fault current detected just noted that the sparker is not running (looks like supply is off or not triggered) scanner looks good |
| Aug 16 2007 10:47:24:090AM | 1070816006 | Jim Irby | 150 kA, 1 s pulse
no detectable fault on gf Pearson realtime mb53, mb54, signals clean |
| Aug 16 2007 11:44:44:423AM | 1070816007 | Jim Irby | went into cell and found sparker trigger disconnected (???). Sparker test shot okay now.
150 kA, invert a +1 s, TF pulse, PLC Vincent opens CNPA gatevalve --- very small, brief rise is pressure prepuff from 20 to 27 ms (cryopump will be used on first plasma shot) loaded into tree ------------------ no faults sparker okay ------------------ |
| Aug 16 2007 12:54:39:613PM | 1070816008 | Jim Irby | people enter cell to check TF power supply
This shot will be a plasma attempt ICRF is ready cryopump is cold ------------------------------------------------------ plasma into rampdown --- h-mode noise on TF bus voltage appears to be coming from chopper see 2 A on TF gf at 4.05 s for about 100 ms |
| Aug 16 2007 01:10:25:350PM | 1070816009 | Jim Irby | extended TF flat-top to 2 s --- get rid of waggle
loaded tree DPCS same otherwise cryopump cold icrf ready -------------------------- plasma into rampdown --- a couple of h-modes no gf detectable real-time taps good |
| Aug 16 2007 01:24:27:960PM | 1070816010 | Jim Irby | Jerry is in command
repeat shot 09 cyropump cold ----------------------- fizzle --- looks like cryopump was dumping before shot no gf scanner good tf taps good |
| Aug 16 2007 01:39:44:010PM | 1070816011 | Jim Irby | Try again
Did recal on seg 2 Ip --- now 0.0 offset ------------------ plasma into rampdown --- a couple of h-modes got proper Ip this time (800 vs 835) hards are gone no gfs taps look good scanner looks good |
| Aug 16 2007 01:54:50:210PM | 1070816012 | Jim Irby | increased nl_04 request to 1.e20/m^2 by 0.5 s
--------- plasma into rampdown --- marfe still having problem with Ip control gf okay taps okay scanner okay |
| Aug 16 2007 02:17:21:377PM | 1070816013 | Jim Irby | nl_04 request dropped to 0.9e20/m^2 at ~.5 s
loaded tree -------------------- plasma into rampdown gf good taps good scanner |
| Aug 16 2007 02:28:01:030PM | 1070816014 | Jim Irby | added point in nl_04 after 0.5 s with peak request to 1.1e20/m^2 --- trying to get higher target w/o marfe
-------------------------- plasma into rampdown -- multiple h-modes and early marfe 120 kJ gf, taps, scanner okay |
| Aug 16 2007 02:54:42:560PM | 1070816015 | Jim Irby | Ip request from 800 to 600 kA
nl_04 request from 1.e20 to 0.8e20/m^2 ----------------- plasma --- still have marfe gf, taps, scanner okay |
| Aug 16 2007 03:10:23:267PM | 1070816016 | Jim Irby | RXU from -.03 to -.02 m
loaded tree -------------- plasma into rampdown gf, scanner, taps okay |
| Aug 16 2007 03:24:44:767PM | 1070816017 | Jim Irby | nl_04 request to 6e19 from 8e19/m^2
---------------- plasma into rampdown, lower density, marfe gone gf,scanner,taps okay |
| Aug 16 2007 03:38:50:910PM | 1070816018 | Jim Irby | nl_04 request to 1e20/m^2
----------------- plasma into rampdown --- marfe gf,scanner,taps okay |
| Aug 16 2007 03:54:39:800PM | 1070816019 | Jim Irby | reloaded shot 1070816011
---------------- dud --- fill pressure has been low most of day |
| Aug 16 2007 04:15:53:543PM | 1070816020 | Jim Irby | prepuff to 31 ms
------------------ plasma ---- all okay |
| Aug 16 2007 04:25:07:070PM | 1070816021 | Jim Irby | repeat DPCS
--------------------- plasma gf,scanner,taps okay problem with YAG |
| Aug 16 2007 04:32:19:720PM | 1070816022 | Jim Irby | no cryopump for this shot
prepuff from 30 to 20 ms ---------------- plasma |
| Aug 16 2007 04:53:28:557PM | 1070816023 | Jim Irby | loaded shot 1070816016
ip request to 400 kA nl_04 request to 6e19/m^2 prepuff to 32 ms loaded tree --------------------------- plasma gf, scanner, taps okay |
| Aug 16 2007 05:00:24:720PM | 1070816025 | Steve Wolfe | Shot#25: Load from 1070803032, verify seg1 on, segs 2-4 off. BEam-into-gas (NO FIELDS) Load at 16-Aug-2007 16:59:36.00 Open tree /home/wolfe/pcs_scratch -1 Open tree done PCS is ready for beam-into-gas shots |
| Aug 16 2007 05:39:29:267PM | 1070816027 | Steve Wolfe | SHot#27: Third shot of beam-into-gas. Successful. Done with Beam-into-gas shots, END OF RUN |
| Engineering Operator Comments | ||||
| Shot | Time | Type | Status | Comment |
| 1 | 08:51:11:783AM | Test | Ok | TF Scanner |
| 2 | 09:08:28:053AM | Test | Ok | TF 10 KA |
| 3 | 09:34:48:303AM | Test | Bad | Igor failed |
| 4 | 09:58:47:440AM | Test | Ok | TF 50 KA |
| 5 | 10:12:27:847AM | Test | Ok | TF 100kA PLC TEST |
| 6 | 10:27:44:473AM | Test | Ok | TF 150 kA |
| 7 | 11:26:12:137AM | Test | Ok | TF 150KA 2sec |
| 8 | 12:10:03:013PM | Plasma | Ok | |
| 9 | 12:57:28:960PM | Plasma | Ok | |
| 10 | 01:13:12:507PM | Plasma | Ok | |
| 11 | 01:28:42:417PM | Plasma | Ok | |
| 12 | 01:43:07:713PM | Plasma | Ok | |
| 13 | 01:57:58:017PM | Plasma | Ok | |
| 14 | 02:17:26:830PM | Plasma | Ok | |
| 15 | 02:33:04:927PM | Plasma | Ok | |
| 16 | 02:59:08:160PM | Plasma | Ok | |
| 17 | 03:12:08:097PM | Plasma | Ok | |
| 18 | 03:26:56:350PM | Plasma | Ok | |
| 19 | 03:43:27:553PM | Plasma | Ok | |
| 20 | 03:57:01:150PM | Plasma | Ok | |
| 21 | 04:13:50:060PM | Plasma | Ok | |
| 22 | 04:26:36:900PM | Plasma | Ok | |
| 23 | 04:42:22:543PM | Plasma | Ok | |
| 24 | 04:55:30:670PM | Plasma | Ok | |
| 25 | 05:12:42:593PM | Test | Ok | Beam into Gas |
| 26 | 05:22:19:747PM | Test | Ok | Beam into Gas |
| 27 | 05:32:26:133PM | Test | Ok | Beam into Gas |
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