29 June 2012 Author: Lester M. Waganer, firstname.lastname@example.org-->
ARIES Documents -- Meetings ArchiveARIES Conference Call, 30 October 2012
Documented by L. Waganer
Les Waganer said he posted a Doodle query on the Web to determine the more preferable meeting dates in the latter part of January 2013. During the call, the team decided the dates of Tuesday, January 22 (all day) and the half day of Wednesday, Jan 23, 2013 would be preferred. The meeting will be held at the University of California, San Diego, CA. The next ARIES conference call will be held on Tuesday, December 11 at 9:30 PST.
Farrokh told the team that the ACT-1 physics parameters, design concept and analysis results should be documented in papers to be published in a technical journal, such as the ANS FS&T. He volunteered to create a list of suggested papers to be published.
ARIES Technical Efforts
Reliability Modeling and Advanced Structural Analysis - Tom Weaver noted Dan Driemeyer is working on a proposal and hopes to soon be engaged on the divertor structural material analysis. Ali is working on the divertor reliability analysis.
Power Core Design - Siegfried Malang said that he had spent some time in San Diego working with Mark Tillack and Xueren Wang on the power core, principally on the structural support ring and coolant configurations.
Steady-State Plasma Solutions - Alan Turnbull reported that he and Holger St. John are making progress with the plasma simulation code. He mentioned changes were made in the frequencies of the lower hybrid heating and current drive system to improve plasma penetration.
Divertor Modeling and Experimental Correlations - Said Abdel-Khalik provided an update on the progress to correlate analytical and experimental results for the divertor maximum heat flux and pumping power. Specifically, they are trying to analyze the relative importance of conduction through the walls of the divertor structure, vs. convection at the surface cooled by helium, for different structural materials and different divertor designs. Their goal is to develop robust correlations that can be used to predict thermal performance and design efficient divertor concepts.
Plasma Modeling in the Divertor Region - Marv Rensink reported that they have not created any new ACT-1 plasma/divertor simulations, but they have updated their ITER divertor simulation for comparison purposes. Marv suggested that he and Tom will author a journal paper on their work and results that would supplement contributions to papers authored by Chuck Kessel on the plasma physics and Alan Turnbull on plasma modeling.
ASC Modeling Progress - Mark Tillack has been addressing and working on the costing concerns voiced by Les Waganer at the September meeting. Mark has solved the cost escalation error, but resolution of the costing discrepancy between two output files is proving to be more difficult. He has gotten it to be a minor discrepancy, with the Cost Accounts file being more likely to be correct.
Mark mentioned that Chuck Kessel is using his physics/engineering code to explore design space for the ACT-2 concept. The initial scan resulted in very large (or low net electric) devices using lower values of beta. The ARIES Systems Code will be used to define the most desirable design points once a reasonable design space is identified.
Mark said that he had been analyzing the helium coolant ducts for the divertor. He had assumed that minimum pumping power would be using one large duct. However a more detailed analysis suggests that two smaller ducts might result in lower power consumption. He is trying to keep the pumping power below 5 MW/divertor.
Mark noted that Xueren and he will try to gain space for a bottom vacuum pumping duct per the September ARIES project meeting action item. This will be initiated when Xueren returns from vacation.
Mark said that he and Laila are analyzing how to reduce the heat in the low temperature shield as currently the shield is generating too much heat, which cannot be effectively utilized.
ATC-2 Radial Build - Laila El-Guebaly replied that she is working on the radial build for the ACT-2 to first address the breeding problem. She is trying to achieve the necessary TBR, keep the shielding adequate for the inner and outer components and capture the maximum heat. It is difficult as there is no actual basic design concept yet.
Nuclear Heating - Laila noted the ACT-1 nuclear heating is influenced by the changes in the vacuum vessel and the low temperature shield. Her analysis currently indicates the VV will generate 22 MW and the LT shield will generate 74 MW of thermal power. The energy multiplication and component lifetimes will be impacted with the changes to the IB blanket and Structural Ring from the ACT-1 design approach. She is considering increasing the thickness of the inboard radial build to help reduce the ~100 MW of non-usable thermal power. Perhaps Mark could investigate this approach parametrically with the Systems Code.
Divertor Structural Analysis - Jake Blanchard is working on a parametric stress analysis on the divertor for varying heat flux levels. He has not started working on the finger-type divertor design yet.
Vacuum Vessel Design and Analysis - Farrokh Najmabadi said that he will have a student continue to work on the vacuum vessel design and analysis effort. If available, the disruption loads will be implemented in the analysis. The analysis will also incorporate the nuclear heating loads provided by Laila. Farrokh's current design concept will use near-atmospheric pressure helium gas to remove the nuclear heating in the VV, which will not be used in the thermal conversion cycle.