| Miniproposals | ||||||||||
|
| Operators | |
| Session leader(s): | Miklos Porkolab |
| Physics operator(s): | Earl Marmar |
| Engineering operator(s): | Unknown |
| Engineering Operator Run Comment |
| MP#351 and MP#353 Marmar |
| Session Leader Plans |
| Physics Operators Plans |
| Session Leader Summaries |
| Entered: Jul 7 2004 03:49:33:820PM |
| Author: Miklos Porkolab |
| Run Summary Overall a good run. Images of eleven pellet injections were taken after overcoming initial problems with the setup of the PSI camera. Six sets of images were taken during ohmic operation, and five sets of images were taken during rf operation, three of these occurring while the plasma was in H-mode. In all, a good radial scan of the plasma was made during both modes of operation yielding high quality images of the ablation striations. |
| Entered: Jul 7 2004 03:49:33:820PM |
| Author: Miklos Porkolab |
| Summary of Miniproposal 351: q-Profile Control and ELMy H-Mode Studies with Ip Ramp and ICRF Heating. Session Leader : M. Porkolab; Phys. Op E. Marmar; RF Ops Y. Lin and S. Wukitch Visiting RF Ops: G. Schilling and R. Wilson Overall, a successful day and achieved most of the goals of the experiment. In particular, we gave priority to Howard Yuh's MSE experiment to collect data for his thesis and hopefully show that reversed shear profiles are achieved during the current ramp, before sawteeth set in. The following were achieved: Established current ramp-up to 0.8 MA at 5.4 T during the initial 0.2 sec. RF power was maximized up to 4.4 MW, with D, E and J ports (1+1+2+MW approximately). Obtained H mode with and without ELMs in the ramp-up phase and later. Carried out experiments with J + E port power only, with J port only up to 2.8 MW (steady RF pulse), as called for in the run-plan. Results are similar to last October's run, namely we got ELMy and ELM free H modes. Detailed comparison will have to be made to see if "central heating only" is as effective as last year's simultaneous "central and off-axis " heating. Sawteeth were "delayed" to 0.31 sec (typical) with RF, however, in OH cases sawteeth came in at 0.28 sec while edge and central temperatures were only half those of the RF case. It may be that the higher impurity levels and Zeff make up for the higher temperatures with RF and therefore the current penetration time is not significantly delayed with early RF heating. Further assessment of this explanation will have to be carried out. H. Yuh will have to analyze the data to see if he will get good q-profiles during the ramp-up phase. Unfortunately, he did not get all the "beam into gas" calibration shots at the end (he needed 3 "beam into plasma" shots without RF, and he needed at least 4 "beam into gas" shots, with B field only). He did not complete the last two shots with "beam into gas". Also, we did not have a chance to try the 4.5 Tesla case to see how "off-axis heating only" compares with "on-axis" heating only. See logbook entries for more details. |
| Physics Operator Summaries |
| Entered: Jul 7 2004 04:37:18:753PM |
| Author: Earl Marmar |
| Physop run summary 1030709 PO Marmar MP 351 q-profile control and ELMy H-Mode studies (SL Porkolab) MP 353 Li pellet striation studies, piggyback (SL Bose) This run featured strong rf heating during the current ramp-up, and Li pellets into both ohmic and RF parts of discharges. The final 3 shots were beam into gas with fields for MSE calibration. See session leader summaries for details. The machine ran quite well. There was a torvac failure after shot 22, which was reset within about 10 minutes, and did not seem to cause any problems. However, there was another torvac failure after the last pulse (35) and the pressure in the torus rose to about 1 Torr during the pulse. It took several hours to get torvac back, and then the vessel was pumped out. There were 2 duds (3 and 26) where the fields and gas looked fine. The fill was raised slightly for 4, and no changes were made for 27; both 4 and 27 were fine. The a-coils were used for most of the run. On shot 30, we reloaded an old shot, (1030613019) into segment 2, and left the a-coils off (unintentially). This was a 1 MA plasma that disrupted near the end of the RF pulse. The interferometer also failed on this shot, turning off the gas early. Scorecard: Plasmas 28 P.S. Dud 1 Duds 2 Fizzle 1 Beam into gas 3 Cycles 35 |
| Session Leader Comments | |||
| Jul 9 2003 09:20:42:213AM | 1030709001 | Miklos Porkolab | First shot fired, got H mode, total power was 3.5 MW. after 0.25 sec. However, during ramp power was only from D and E ports, total power only 1.5 MW; J port power came on to late, at 0.25 sec. Need to couple more power during ramp, 0.1-0.2 sec. |
| Jul 9 2003 09:16:13:610AM | 1030709003 | Miklos Porkolab | Dud. No plasma; Unclear why. |
| Jul 9 2003 09:47:23:280AM | 1030709004 | Miklos Porkolab | Need more power early on. Power is only 1.5 MW from D and E ports. J port is not staying on early into the shot, comes on at 0.2 sec and gets into EDA. No ELMy H mode early on. |
| Jul 9 2003 09:54:22:417AM | 1030709005 | Miklos Porkolab | D port is down. E port gives 1.0 MW, J port does not stay on until late into the pulse. |
| Jul 9 2003 10:29:55:610AM | 1030709006 | Miklos Porkolab | D port is still down, J is getting better early , but dropped out a few times. Edge temperature looks promising while the J port is on at 0.12 sec. Next shot will get D port back. Clearly, need more power early on to try to get ELMy H mode. |
| Jul 9 2003 10:51:22:777AM | 1030709007 | Miklos Porkolab | Looks promising, looks like trying to get into H mode at 0.175 sec while the J ort and E and D ports are all on. Still limited on the inner plate. Need to maintain J port on longer. |
| Jul 9 2003 11:17:28:157AM | 1030709008 | Miklos Porkolab | Looks promising, power up to 4 MW at 0.12 sec; Getting H mode. Sawteeth delayed to 0.3 sec. |
| Jul 9 2003 11:30:39:290AM | 1030709008 | Miklos Porkolab | Good shot, RF power staying at 4 MW. Sawteeth still delayed to 0.3 sec. |
| Jul 9 2003 11:36:21:630AM | 1030709010 | Miklos Porkolab | Lowered density. Got ELMy H mode. Edge temperature up to 0.5keV. Looks very interesting between 0.15 to 0.25 sec. ELMy H mode. Then get collapse at 0.28 sec as Zeff shoots up. Neutron rate up to 2x10^13 just before collapse. J port RF did not come on until 0.13 sec. Density too high for NBI during H mode. |
| Jul 9 2003 11:46:24:680AM | 1030709011 | Miklos Porkolab | Good shot. Got H mode again at 0.17 sec with 4 MW RF. Some ELMs, not very large. High Te-edge during build up of H mode, 0.5 keV . Diverted discharge but still touching edge of inner limiter at 0.17 sec. Becomes clearly diverted at 0.24 sec. |
| Jul 9 2003 12:19:36:760PM | 1030709012 | Miklos Porkolab | Similar shot to before, 011. |
| Jul 9 2003 12:27:59:137PM | 1030709012 | Miklos Porkolab | ELM build-up from 0.160 to 0.165 sec at 4.1 MW, simultaneously enter H mode. Tedge at 0.5 keV, central Te at 3.0 keV. H mode collapse at 0.28 sec due to large impurity buildup. Enter Elm free H mode . High power (4 MW) RF stays on until 0.5 sec. |
| Jul 9 2003 12:36:16:930PM | 1030709013 | Miklos Porkolab | Enter H mode again, with 3 -4 MW (dropping in and out). Get ELMS and get in and out of ELM free H mode until 0.3 sec. Zeff stays around 3 until 0.3 sec. Neutron rate at 1-2.5x10^13 during H mode. Tedge up to 0.6 keV. |
| Jul 9 2003 12:44:51:573PM | 1030709014 | Miklos Porkolab | Similar to shot 13, except RF even more irregular, dropping in and out from 3-4 MW. E port antenna not coupling well now, but changed plasma shape, moving it away from inner wall/ limiter corner. Plasma fully diverted abot 0.22 sec. Lots of large ELMs but interpretation will be difficult due to non-steady RF ? |
| Jul 9 2003 12:59:48:947PM | 1030709015 | Miklos Porkolab | No RF shot, for background comparison for NBI. Plasma became diverted at 0.22 sec. NBI did not fire, have to repeat it. Need 3 "no RF" shots for NBI. Sawteeth come in at 0.28 sec. Is that significant ? With RF sawteeth come in around 0.31 sec. But the peak temperature without RF is 1.9 keV and T_edge is 0.25 keV only. |
| Jul 9 2003 12:57:50:037PM | 1030709016 | Miklos Porkolab | Another no RF calibration shot. Beam on this time. Repeat again. |
| Jul 9 2003 01:35:03:390PM | 1030709017 | Miklos Porkolab | Bad ohmic shot, need to repeat again. |
| Jul 9 2003 01:51:42:217PM | 1030709018 | Miklos Porkolab | Good ohmic shot for MSE calibration. Pellet fired at 1.3 sec, getting good data. Camera working now. |
| Jul 9 2003 02:16:11:233PM | 1030709019 | Miklos Porkolab | No changes. Ohmic plasma. |
| Jul 9 2003 02:23:38:543PM | 1030709020 | Miklos Porkolab | No cnange. |
| Jul 9 2003 02:35:53:693PM | 1030709021 | Miklos Porkolab | Inject RF to begin MSE scan. |
| Jul 9 2003 02:51:44:787PM | 1030709022 | Miklos Porkolab | Injected pellet at 0.25 sec into H mode, but shot off RF power. Also, RF shut off earlier. Trying to give repeated shots to MSE and Pellet with RF on. |
| Jul 9 2003 03:20:16:573PM | 1030709023 | Miklos Porkolab | It was a reasonable shot for MSE. Injected 4 MW, with a partial trip at 0.22 sec. Also got a large ELM, and got into ELM free H mode at 0.22 sec, followed by impurity accumalation and collapse at 0.27 sec, with RF staying on. There was no pellet injection in this shot. Otherwise got good H mode. Interesting fact; the plasma is pulled away from the corner of the inner divertor, and becomes fully diverted at 0.22 sec, just when get into ELM free H mode. T_edge=0.55 keV, T_e=3.5 keV, nl_04(max) = 1.2. For the next several shots, will inject J port power only for MSE, to reduce stray light. |
| Jul 9 2003 03:36:01:310PM | 1030709024 | Miklos Porkolab | Had both E and J port RF on. Shot same as before, but only at 3 MW, D port antenna not firing. H mode collapsed earlier, around 0.25 sec, due to immpurity accumulation (Elm free H mode). |
| Jul 9 2003 03:50:00:210PM | 1030709025 | Miklos Porkolab | J port power only. 2.5 MW injected. A few trips, in particular at 0.24 sec, before the pellet was injected. RF off when pellet injected at 0.25 sec. |
| Jul 9 2003 03:50:56:180PM | 1030709026 | Miklos Porkolab | Dud. |
| Jul 9 2003 04:13:53:333PM | 1030709027 | Miklos Porkolab | Very different shot in that RF (J port only) drops out around 0.18 sec, then large ELMs come in as plasma cools, then RF recovers at 0.20 sec, but H mode does not recover. Then pellet fires in at 0.25 sec and get PEP mode. Prf=2.6 MW, T_e=3.5 keV, T_edge=0.5 keV at max value. Not a particularly efficient H mode, density rise minimal even in the early phase. |
| Jul 9 2003 04:44:37:283PM | 1030709028 | Miklos Porkolab | Repeat shot for MSE, J port power only. Looks like L moode shot. |
| Jul 9 2003 04:57:10:323PM | 1030709029 | Miklos Porkolab | Steady RF power, 2.8MW J port. Good shot for MSE. Interesting shot, got couple of large ELMs, got H mode, got high edge Te (0.5 keV) and then got into ELm free H mode and then collapsed back into L mode at 0.27 sec. Te=3.0 keV. Impurity radiation very large during ELM free H mode. |
| Jul 9 2003 05:01:48:363PM | 1030709030 | Miklos Porkolab | Shot is very "ugly". Plan was to give L mode shot at 600 KA to MSE, up to 0.25 sec, then ramp current to 1.0 MA and inject 4 MW + power, with pellet injection around 0.3 sec. However, shot was badly affected with material injection, radiation, loss of plasma control, etc. |
| Jul 9 2003 05:19:00:147PM | 1030709031 | Miklos Porkolab | Fizzle. |
| Jul 9 2003 05:37:54:433PM | 1030709032 | Miklos Porkolab | Repeated shot with: initial phase for MSE calibration only, Ip=600 kA, low density L mode up to 0.3 sec. Then starting at 0.7 sec, ramp current to 1.0 MA, inject pellet at 0.8 sec, and at the end of the ramp, immediately after the pellet, inject RF power at 4 MW . Result is: early phase of shot OK for MSE; however, RF tripped 3 times, making 3 H-mode phases for short time, then trip. Edge temperature rose to about 0.6 keV during RF phase. |
| Physics Operator Comments | |||
| Jul 9 2003 08:55:40:553AM | 1030709001 | Earl Marmar | load segment 1 from 1030708017 segment 2 from 1021025026 add the a-coil, on at 0.1, ramping to 4000 at 0.3, off from 1.5 to 1.7 reduce I_p to 0.8 MA (from 1.0 MA) plasma early H-Mode |
| Jul 9 2003 08:58:05:480AM | 1030709002 | Earl Marmar | no pcs changes power supply dud; no TF |
| Jul 9 2003 09:15:20:733AM | 1030709003 | Earl Marmar | no pcs changes dud; fields look ok; sparker looks the same as on shot 1 |
| Jul 9 2003 09:29:00:650AM | 1030709004 | Earl Marmar | add 1 msec to prefill puff plasma Li pellet at 1.3 seconds |
| Jul 9 2003 09:29:40:463AM | 1030709004 | Earl Marmar | after the shot, power room access for RF to look at transmitter 1 |
| Jul 9 2003 09:53:25:870AM | 1030709005 | Earl Marmar | no pcs changes plasma injection(s) around 100 msec, current falls for a while |
| Jul 9 2003 10:23:38:910AM | 1030709006 | Earl Marmar | no pcs changes plasma Li pellet at 1.3 s; psi camera not working |
| Jul 9 2003 10:38:19:957AM | 1030709007 | Earl Marmar | no pcs changes plasma pellet at 1.3 s; no psi camera data |
| Jul 9 2003 10:47:57:427AM | 1030709008 | Earl Marmar | no pcs changes plasma >4MW RF |
| Jul 9 2003 11:16:39:420AM | 1030709009 | Earl Marmar | no pcs changes plasma disrupted after Li pellet(s); looks like 2 came out. |
| Jul 9 2003 11:22:47:133AM | 1030709010 | Earl Marmar | lower early nl_04 programming plasma more radiated power, no second h-mode |
| Jul 9 2003 11:56:55:217AM | 1030709011 | Earl Marmar | no pcs changes plasma |
| Jul 9 2003 11:57:19:733AM | 1030709012 | Earl Marmar | no pcs changes plasma |
| Jul 9 2003 12:10:47:727PM | 1030709013 | Earl Marmar | move RXL out early (starting at 0.1 seconds); trying to miss the inner nose around 0.17 seconds plasma not completely clear of nose until 0.24 |
| Jul 9 2003 12:44:56:043PM | 1030709014 | Earl Marmar | tweak early rcur and clearin; try to move farther away from nose plasma missing the nose by 0.22, but grazing the outer limiter at 0.12 |
| Jul 9 2003 01:03:29:373PM | 1030709015 | Earl Marmar | no pcs changes no RF requested plasma |
| Jul 9 2003 01:03:43:343PM | 1030709016 | Earl Marmar | no pcs changes plasma |
| Jul 9 2003 01:10:22:077PM | 1030709017 | Earl Marmar | no pcs changes plasma very early disruption; junk coming in around 115 ms, finally dies at 180 ms. |
| Jul 9 2003 01:47:27:303PM | 1030709018 | Earl Marmar | no pcs changes plasma Li pellet at 1.3 seconds; beautiful cigars |
| Jul 9 2003 02:00:58:313PM | 1030709019 | Earl Marmar | no pcs changes plasma good Li pellet data, 1.3 s |
| Jul 9 2003 02:13:43:197PM | 1030709020 | Earl Marmar | no pcs changes good Li cigar data, pellet at 1.3 s |
| Jul 9 2003 02:55:22:357PM | 1030709022 | Earl Marmar | no pcs changes plasma pellet into early h-mode (0.25 s) |
| Jul 9 2003 03:15:40:300PM | 1030709023 | Earl Marmar | no pcs changes plasma no pellet (gate valve disabled by torvac) |
| Jul 10 2003 03:44:16:103PM | 1030709023 | Ron Parker | Shot 23 started up OK, but disrupted @ 0.7 sec. |
| Jul 9 2003 03:26:59:480PM | 1030709024 | Earl Marmar | no pcs changes plasma |
| Jul 9 2003 03:55:07:203PM | 1030709026 | Earl Marmar | no pcs changes dud; fields and fill look ok |
| Jul 9 2003 04:09:59:843PM | 1030709027 | Earl Marmar | no pcs changes plasma pellet at 0.25 s (RF l-mode phase) |
| Jul 9 2003 04:28:30:643PM | 1030709028 | Earl Marmar | no pcs changes plasma |
| Jul 9 2003 04:28:59:740PM | 1030709029 | Earl Marmar | no pcs changes plasma |
| Jul 9 2003 05:09:17:830PM | 1030709030 | Earl Marmar | load segment 2 from 1030613019, change to ramp to 1 MA after 0.6 seconds a-coils off went bad early, I_p turned back to 200 kA, then recovered disrupt near end of RF at 1 MA Interferometer went wild and turned off the gas early |
| Jul 9 2003 05:10:30:160PM | 1030709031 | Earl Marmar | turned on a-coils reduce prepuff 1 msec fizzle |
| Jul 9 2003 05:36:25:320PM | 1030709032 | Earl Marmar | reduce prefill 1 more msec plasma pellet at 0.8, then RF |
| Jul 9 2003 05:54:23:603PM | 1030709033 | Earl Marmar | beam into gas with TF and EF4 load from 1030521008 got the fields, gas and beam |
| Jul 9 2003 05:55:40:593PM | 1030709034 | Earl Marmar | beam into gas with TF, EF3 and EF4 load from 1030521013 got fields and gas; beam reported to be poor |
| Jul 9 2003 06:20:22:797PM | 1030709035 | Earl Marmar | beam into gas with TF, EF3 and EF4 load from 1030521014 got fields and gas, poor beam. something bad happened to torus pressure after 0.4 seconds; gate valves closed |
| Engineering Operator Comments | ||||
| Shot | Time | Type | Status | Comment |
| 1 | 08:29:00:270AM | Plasma | Ok | |
| 2 | 08:52:08:580AM | Plasma | Bad | No TF |
| 3 | 09:04:52:807AM | Plasma | Ok | |
| 4 | 09:17:52:567AM | Plasma | Ok | |
| 5 | 09:42:16:160AM | Plasma | Ok | |
| 6 | 09:56:24:720AM | Plasma | Ok | |
| 7 | 10:23:09:300AM | Plasma | Ok | |
| 8 | 10:36:06:327AM | Plasma | Ok | |
| 9 | 10:54:49:753AM | Plasma | Ok | |
| 10 | 11:16:18:230AM | Plasma | Ok | |
| 11 | 11:30:02:617AM | Plasma | Ok | |
| 12 | 11:44:14:347AM | Plasma | Ok | |
| 13 | 11:58:23:233AM | Plasma | Ok | |
| 14 | 12:15:51:080PM | Plasma | Ok | |
| 15 | 12:35:44:070PM | Plasma | Ok | |
| 16 | 12:49:30:097PM | Plasma | Ok | |
| 17 | 01:05:26:067PM | Plasma | Ok | |
| 18 | 01:37:21:720PM | Plasma | Ok | |
| 19 | 01:50:33:073PM | Plasma | Ok | |
| 20 | 02:03:56:240PM | Plasma | Ok | |
| 21 | 02:17:20:610PM | Plasma | Ok | |
| 22 | 02:32:27:703PM | Plasma | Ok | |
| 23 | 02:58:13:767PM | Plasma | Ok | |
| 24 | 03:19:41:590PM | Plasma | Ok | |
| 25 | 03:33:26:740PM | Plasma | Ok | |
| 26 | 03:46:37:657PM | Plasma | Ok | |
| 27 | 03:59:28:870PM | Plasma | Ok | |
| 28 | 04:12:43:957PM | Plasma | Ok | |
| 29 | 04:26:16:420PM | Plasma | Ok | |
| 30 | 04:48:20:930PM | Plasma | Ok | |
| 31 | 05:07:41:827PM | Plasma | Ok | |
| 32 | 05:23:03:217PM | Plasma | Ok | |
| 33 | 05:36:51:993PM | Test | Ok | TF & EF4 only |
| 34 | 05:50:06:283PM | Test | Ok | TF, EF3, EF4 |
| 35 | 06:04:36:827PM | Test | Ok | TF, EF3, EF4 |