ARIES Documents -- Meetings ArchiveARIES Conference Call, 12 January 2012
Documented by L. Waganer
Les Waganer mentioned the next ARIES meeting is scheduled on Monday, January 23 (afternoon only) and Tuesday, January 24 at UCSD, Engr Building 1, Room 6504 (CWC conference room). Les Waganer has distributed the draft agenda to all team members. All presenters were satisfied with the titles and allocated times. More time is available for other presenters. A speaker phone will be available in the room for distance participation.
ARIES Project Near and Long-term Goals
Farrokh Najmabadi stressed achieving our near-term goal of completing our current project within 18 months.
ARIES Technical Efforts
Lane Carlson noted that the SCLL version of the ASC code has been completed and is ready for use. He is working on documentation in the ARIES ASC web page, which is nearly complete. This page will present the code history, documentation of the module data and equations, strawmen points (data sets) and the Visual ARIES Systems Scanning Tool.
Xueren Wang has been working to complete his October action items. He has completed the power core configuration definition. He has incorporated the latest versions of the SCLL blankets in the power core designs. He has also been improving the vacuum vessel with the latest configuration changes and modifications to the vacuum vessel main maintenance door to accommodate vertical retraction of the control coils. Horizontal maintenance remains the configuration of choice. The feedback coils (or saddle coils) would be attached to the vacuum vessel door, and removed together with the door. Farrokh mentioned that recent stress analysis of the vacuum vessel may allow thinner VV sections. Xueren is working on the helium-cooled shield design to provide more fidelity to the power core design and analyses.
Mark Tillack remarked that he, also, is working on the resolution of his action items, especially the manifolding near the PF and TF coils. He researched and found the ARIES-AT PF magnetic fields at the manifold connections were in the neighborhood of 5 T. This is quite high for MHD effects. Mark is working to map the local PF fields to provide an improved data base for future MHD analyses. Siegfried Malang noted to Mark that the curved rectangular LM pipes will have a stagnant flow region that will result in higher local temperatures, which would tend to depress peak and average coolant temperatures (to keep local temperatures below the maximum temperature condition).
Siegfried is preparing a revised DCLL manifolding and connection configuration to improve the present DCLL design. This improvement should lessen the 3D MHD effects of the prior design. This design will not be applicable to a single coolant LM design without some redesign.
Jake Blanchard is working to complete his action items. He has made progress on the 3D fracture analysis on the divertor, which he will document at the meeting. At Les Waganer's suggestion, Jake will also describe the recommended design loads for the ARIES vacuum vessel based on the more detailed ITER vacuum vessel stress analyses.
Tom Weaver noted that Boeing has a current contract in place, but the period of performance has expired effective 31 December 2011. The contract cannot be extended by UCSD until they also get an extension or a new contract and POP. Tom did say Boeing has charging procedures and people in place to commence the desired ARIES work (divertor material and reliability modeling).
Paul Humrickhouse mentioned that he is modeling the ARIES-AT power core with the MELCOR code to better predict the tritium inventory and safety issues. This effort will be presented at the January meeting. He also has been working on tritium permeation issues.
Marv Rensink has been cataloging over 100 plasma simulations conducted with the UEDGE code and inputting this data into a common spreadsheet database. This is helpful in understanding and accessing common trends and underlying concepts. He has found that divertor-attached plasmas have very high and unacceptable heat and particle fluxes. It is desirable to have a detached plasma that should have divertor heat fluxes at 10 MW/m2 or less. Marv also felt that he needed to address and better understand effects of the plasma profiles and pedestals. He commented that in his simulations, he has found that using prior stable plasma solutions and making small input changes, the simulation will oscillate and not reach a stable steady state. He feels that in some cases this is a mesh problem and a finer mesh might solve the stabilization problem - will report on this at the meeting.
Alan Turnbull has been interacting with Chuck Kessel to reach a steady-state plasma solution for the advanced ACT physics data set. He has been plagued with collapsing plasma profiles, however he and Chuck think that adding auxiliary heating (per the currently defined levels) may solve the problem. (At present, there is no auxiliary heating power included in the simulations.) The additional heating probably will be ICRH per the ASC code parameters (~ 40 MW). If this does not solve the issue, other heating means will be considered. Farrokh asked about the conservative physics case and Alan thought that case would be much easier to solve and would not require much time and effort. Marv asked about the accessibility of the EQDSK solutions for the ARIES-ACT plasmas - Alan thought Chuck Kessel might have them or could generate them, but they would not be needed until after the January 2012 meeting.