ARIES Documents -- Meetings ArchiveARIES Conference Call, 19 January 2005
Documented by L. Waganer
The next ARIES meeting will be held at General Atomics on Thursday, 24 February, and a half day on Friday, 25 February. Alan Turnbull is the host and would appreciate knowing who will attend. He also needs to be advised of any non-US person that wishes to attend the meeting. If you would like to use your laptop for internet access, there is a GA form you need to sign and return before the meeting. You can find the form at the GA Fusion Website. Les Waganer will be preparing an agenda shortly.
The following meeting will be at Madison, WI, in June 2005. Les Waganer will query the team on suitable days. The September meeting will be at PPPL and will probably have a town meeting format. The December meeting will be at San Diego.
Farrokh Najmabadi, Jim Lyon, Long-Poe Ku, and Rene Raffray attended the US/Japan Workshop held in Tokyo, Japan on 11-13 January 2005. The ARIES team presented their current findings and research direction for the ARIES Compact Stellarator. The ARIES presentations have been added to the ARIES web site for viewing. There was minimal feedback on the ARIES-CS presentations from the other participants as they are working in different research areas. However, there does seem to be increased general collaboration between the US, JA, and EU.
Rene Raffray introduced Thomas Ihli from FZK as a visiting member of our ARIES team. He will spend six months at UCSD and will work on divertor engineering. He will make a presentation at our February meeting on helium-cooled divertor engineering analysis and design.
Compact Stellarator Reactor Physics Basis
Assessment of Prompt Alpha Loss – T.K. Mau mentioned that Paul Garabedian visited UCSD last week and conferred with TK on the modeling of a new two-field period, 16-coil configuration that Paul generated and analyzed. His analysis predicts alpha losses less than 10%. He has been modeling the plasma and coils. The coils seem to have considerable maintenance space between coils. He has worked with Xueren Wang who has generated CAD drawings of the coil sets. He is lacking information on the parameters Bmax/BO. Paul will be meeting with Long Poe Ku at PPPL to see if he can help generate this information.
TK has conducted two conference calls with Hayden McGuinness and Arthur Grossman on the CS divertor definition regarding plasma parameters. The issue with the non-alignment of the last closed magnetic surfaces (LCMSs) between VMEC and MFBE has been resolved by Art. Hayden made good progress in getting the parallelized version of Gourdon to run on Seaborg in NERSC. The code has already been shown to run properly on a single processor.
TK also worked with Lang Lao to get the VMEC equilibrium for the new 2-FP case with R=8, A=2.5, using an assumed rotational transform profile. An equilibrium condition with a self-consistent iota profile will be worked out.
TK is working on a gyro-ORBIT code and will have some results to show at the next meeting
Assessment of New QAS and QH configurations – Long-Poe Ku is continuing to investigate the plasma and coil definition of new three-field period configurations. He has found configurations with field errors of ~1%. He is analyzing the free boundary conditions for low alpha losses associated with surface ripples. He will present his findings at the February meeting.
Compact Stellarator Integrated Systems Assessment
Systems Code Analysis – Jim Lyon has been able to work on his systems assessment code – refining and debugging. The previous code results should be removed from the ARIES web. He will supply new results for posting, either before or after the meeting. He has added two new NCSX-like configurations. He has incorporated new blanket and shielding data that was provided for port maintenance configurations. He would like to receive shield data for incorporation into a modular replacement configuration analysis.
Compact Stellarator Reactor Engineering Assessment
System Safety Studies – Brad Merrill has been modeling the safety analyses for the lead-lithium configuration. He will confer with Carl Martin on specific data and assumptions. Carl Martin is continuing his LOCA and LOFA analyses for the proposed configurations.
Blanket and Shield – Laila El-Guebaly said she was focusing on the dual-cooled helium and LiPb FS blanket configurations. Presently, she said the WC shield-only regions amount to 5% of the wall area, 10% to a transition zone, and the remaining 85% is the blanket region. The divertor would cover ~ 15% of the FW area. The region behind the divertor plates will still be a breeding zone, but just less efficient. More specific data will be provided at the next meeting. Laila needs information on the size and coverage of the LiPb and He manifolds to update the radial builds.
Power Core Engineering – Rene Raffray said the Engineering Group is continuing to analyze and refine the dual-cooled blanket concept as a modular maintenance approach. The current area of investigation is the coolant plenum and manifolds. Xueren is developing CAD drawings of those areas. Siegfried Malang has sent sketches to Xueren for incorporation.
Gas-Cooled Divertor Studies - Said Abdel-Khalik noted that they have completed the liquid-cooled divertor assessment and are proceeding with the helium-cooled divertor approach. He will have some results to present at the upcoming meeting.
Don Steiner asked when the team would select a specific magnetic configuration for the more in-depth engineering and physics assessment. Farrokh said that this subject was discussed in the November meeting. We are currently in the process of narrowing the options. We need to have data on the sector maintenance approach to properly compare it to the modular approach. Jim Lyon said he needed data on the removable shield element (volume, weight, size) to enable a credible comparison.