ARIES Documents -- Meetings ArchiveARIES Conference Call, 20 July 2004
Documented by L. Waganer
Les Waganer summarized the upcoming meeting arrangements. The next abbreviated ARIES meeting will be held at the end of the ANS/TOFE meeting being held in Madison, WI. The ARIES meeting will be held at the Monona Terrace, Hall-of-Ideas-H room, on September 16 (Thursday) from 1:00 to 5:00 CST after the end of the last TOFE Plenary Session. Please bring laptops, portable media (USB flash disks or CDs), or overheads. A digital projector and overhead projector will be available. Les will issue a draft agenda ASAP.
Tentatively, the following ARIES meeting will be held at the University of California, San Diego on November 4 (Thursday) and half a day November 5 (Friday).
It was recommended we have a conference call during August. L. Waganer secured a conference call number of 314-232-3805 on 17 August (Tuesday) at the usual time.
Compact Stellarator Reactor Physics Basis
Plasma and Coil Optimization - Long-Poe Ku is continuing to assess the stability and strong shear effects of the advanced QAS configurations he has been pursuing.
He is also starting an investigation of the quasi-helical configurations. He is hoping it will have some advantages, but he questions if it can be sufficiently compact and still offer advantages similar to the QAS system. ORNL had difficulties in finding configuration solutions with lower aspect ratios. He is considering configurations with aspect ratios around 6 and 3-field periods. He expects to have some results by the September meeting.
Compact Stellarator Integrated Systems Assessment
Systems Code Analysis - Jim Lyon found a plotting error on one of his charts regarding deviation from the 16 Tesla field. The error is not germane to any of his findings or results. He will issue a correction page.
He went to London to meet with some EU stellarator colleagues. He found there is a 2004 update to the H-ISS95 model that will predict better confinement and provides more credible data.
He will meet with Leslie Bromberg soon to discuss coil designs and costing algorithms. He hopes to incorporate these data into the systems code along with new configurations to have revised data at the September meeting.
He and Laila exchanged several E-mails to understand the neutron wall load peaking factor. There is a concern that the German investigators are obtaining a higher peaking factor of 1.8 for HSR-4 with an aspect ratio of 8.6 while UW predicted a lower peaking factor of 1.5 for ARIES-CS with a smaller aspect ratio of 4.5. Laila is confident in her data and thinks she knows why there are differences. The peaking factor is very sensitive to the first wall surface geometry and how it is modeled.
Compact Stellarator Reactor Engineering Assessment
Neutronic Analysis - Laila El-Guebaly is coordinating the CS first wall geometry into the NCMP neutron generation code. Presently, they modeled two cross-sections at 0 and 30 degrees of the geometry. The peak NLW will not occur at the bean shape cross-section. The peaking factor (peak to average) is predicted to be around 1.5. For a fixed FW configuration, a higher ratio is predicted for lower aspect ratios, but the trend may reverse if the FW shape changes. Jim Lyon is most interested in the peak value.Laila is also working with Jake Blanchard on LOCA analysis for the LiPb/FS blanket systems. He will be presenting the interim results at the September meeting.
Liquid-Protected Divertors ñ Said Abdel-Khalik reported they are working on refinements, modifications, and extensions of the experimental and materials systems being investigated.
Power Core Engineering ñ Xueren Wang said that he and Siegfried Malang have been working on the maintenance design of the CS power core, especially controlling the spread of radioactive particles when replacing entire field periods This could be a feasibility issue with this maintenance approach.
Divertor Design Assessment ñ Don Steiner mentioned Hayden McGuinness is continuing to assess divertor designs for compact stellarators. He is concentrating on obtaining representative heating loads that are expected on the divertor plates.