ARIES Documents -- Meetings ArchiveARIES Conference Call, 27 August 2004
Documented by L. Waganer
The next abbreviated ARIES meeting will be held at the conclusion of the ANS/TOFE meeting 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 an overhead projector will be available. Les has issued a draft agenda for comment.
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).
Rene Raffray reminded the team members that will be presenting at TOFE should send the draft manuscripts to Farrokh for approval a week in advance of the meeting. Laila affirmed that wireless access would be available at the TOFE meeting.
Compact Stellarator Reactor Engineering Assessment
CS Divertor - Don Steiner forwarded information that Hayden McGuinness will be going to Garching the first week of September to collaborate with the Stellarator edge physics group. The intent is to develop divertor design options for the ARIES-CS divertor.
Power Core Engineering ñ Rene Raffray reminded the team that in Phase 2 we want to choose a blanket design concept. The intent in the September meeting is to identify important metrics to choose the better blanket approach to proceed into the next phase. The choice of blanket approach is linked to the number of field periods (maintenance access), maintenance approach, port locations, and vacuum vessel position. Rene will present the key metrics in this blanket trade study. At present, the divertor area, geometry, and material composition are not known. Jim will use a percentage of the first wall area for the divertor definition in his code.
Rene mentioned he met with the Stellarator group in Garching to discuss blanket options, divertor designs, field period configurations, and maintenance approaches. They were a little surprised at our consideration of the smaller number of coils and field periods. They voiced some concern regarding the ferromagnetic effect of FS in the Stellarator. We should confirm our findings in this regard. Jim Lyon mentioned this is difficult problem that has not been properly addressed by the fusion community in general. The Japanese and the Germans have done some analysis of this effect.
Neutronic Analysis ñ Laila El-Guebaly reported Jake Blanchard is analyzing a LOCA analysis for the LiPb/FS blanket systems. He has been coordinating with Brad Merrill about the assumptions and requirements. He will be presenting the interim results at the September meeting.
Compact Stellarator Integrated Systems Assessment
Systems Code Analysis ñ Jim Lyon said he met with Leslie Bromberg on coil design and cost definition. He contacted Xueren Wang to obtain first wall areas and blanket/shield volumes from the current CS 2-field and 3-field period configurations. While at UCSD, he met with Rene Raffray and Siegfried Malang on the details of the maintenance scheme for the different approaches. Jim is modifying his systems code to accommodate the provided blanket and shield configurations and geometries. He especially needs the coil-to-coil distance for the maintenance ports.
Jim clarified that he has three distinct codes. One is a spreadsheet to scope the global quantities. The second code is a 1-D TOPCON-model based code to calculate more quantitative data for later use. The third code is the systems code that includes integrated functions and performance prediction. The key to credible results is to benchmark all code results with diagnostic runs to validate the input and output data. The codes were originally generated for tokamaks and then adopted for helical coils. Now he is modifying the codes to accommodate modular CS configurations. The systems code is capable of generating TBR, but he will bypass that module and rely on Lailaís TBR analysis results.
Since the last telecon, Jim is planning to calculate the individual material element volumes and masses within the blanket, shield, and vacuum vessel. These data, with unit value cost algorithms, will enable the costing of the complex geometrical models of the blanket/shield/vacuum vessel elements. Les Waganer will supply the appropriate cost models for inclusion into Jimís codes. The cost data should be escalated to 2004 dollars.
Compact Stellarator Reactor Physics Basis
Physics Assessment of Compact Stellarators ñ Paul Garabedian collaborated with T. K. Mau and Long Poe Ku on the influence of the alpha confinement. He is concerned about excessive prompt alpha power loss. Paul thought the alpha loss would not exceed 10%. Hopefully, he can report his findings at the Madison meeting.
Alpha Confinement in Compact Stellarators ñ T. K Mau is using the ORBIT-3D code to analyze the Compact Stellarator plasmas for alpha loss behavior including footprints that would lead to the definition of the divertor. He believes he has correctly converted from Boozer coordinates to reactor geometry coordinates. Presently, he is predicting alpha losses in the neighborhood of 35% for the two-field period case. Long Po Ku and Paul Garabedian have predicted much lower values. He is planning further coordination with Long Po Ku and Paul Garabedian on this subject.