ARIES Documents -- Meetings ArchiveARIES Conference Call, 12 February 2001
Documented by L. Waganer
The date for the next ARIES meeting was confirmed as 8-9 March 2001 with two full days of presentations. Wayne Meier sent out maps for the meeting location in Livermore near LLNL. Dai-Kai is planning the ARIES Tritium Town Meeting at the same location on 6-7 March. Rene Raffray noted that the Tritium Town Meeting will cover both MFE and IFE related tritium issues.
Simon Yu told the team that a three-day workshop on HI beam transport with self-pinch and preformed channels will be held discussed on February 13, 14, and 15. Craig Olson volunteered to summarize the workshop results at the March ARIES meeting.
Target and Chamber Physics
Ken Schultz mentioned that he has been looking at various target options to be evaluated in addition to the baseline NRL target. He has been conferring with Max Tabak on the laser ID target and the plastic target.
Target Fabrication, Injection, and Tracking
Ron Petzoldt has been looking at the mass production of DD and ID targets. Obtaining the proper isotherms to achieve the required surface finishes is difficult. One approach being defined and evaluated is the use of a fluidized bed to produce high quality, uniform, coated spheres.
Ron reported some progress on the assessment of the reflectivity of the thin gold coating on the targets. He is evaluating a single 300 Ĺ coating on a GDP substrate. He has experimentally measured a reflectance of 95.7% at 600°C and 94% at 1500°C when integrated over all angles.
Ron mentioned some analytical work on a protective sabot that would precede the cryogenic target into the chamber.
TK Mau said he is working on the reflectivity analysis of gold coatings on targets. The reflectivity value will be integrated over all angles. He is using blackbody radiation assumptions. John Sethian mentioned that several other metals could be considered for the coating material, such as Pt, Pd, and Ag, to help obtain a reflective and permeable coating. Laila El-Guebaly noted that silver would not be a suitable choice from the activation standpoint.
Chamber Nuclear Analysis
Laila El-Guebaly is expanding her activation analysis to include W, Pt, Pd, Au and Ag on DD targets. For the HIB hohlraum materials, she is considering Au/Gd, Au, W, Pb, Hg, Ta, Pb/Ta/Cs, Hg/W/Cs, and Pb/Hf.
Chamber Wall Engineering
Several people talked about how the NRL target and spectrum should be scaled up to the Sombrero target yield and its impact on the dry and wetted wall surfaces. It was expected the UW BUCKY code could be used to benchmark against the reference case and then extrapolate to the larger yield cases of more interest. In the mean time, the team can use the reference spectra. It is expected little change in spectra with variations in yield.
Don Haynes discussed the analysis to determine the wall response and material evaporation for various targets, gain curves, and imposed spectra.
Rene Raffray continues to look at the solid and fibrous wall materials with different material combinations to assess their effectiveness to survive the target heat load and spectra. He is expecting to obtain results next week for both carbon and tungsten.
Mike Billone affirmed he would obtain thermal properties (heat capacity and thermal conductivity) of carbon and tungsten at representative high temperatures to help scope the erosion rates and thermal responses of the dry wall concept. He was asked also to supply the vapor pressure curves of the materials. Don Haynes specifically asked about radiation-enhanced sublimination (RES) data.
Final OpticsNo data preseented.
Safety and Environmental Impact
Dave Petti and Jeff Latkowski have been identifying the accident initiators and scenarios. Dave is integrating Don Steiner’s off-normal event identification into his accident analyses. Jeff Latkowski is working on the Master Logic Diagram to help model accident initiators. Carbon oxidation is viewed as a significant accident scenario.
Target Fabrication, Injection, and Tracking
Ron Petzoldt discussed his progress of target tracking and mass production of layered targets. He is assessing the fluidized bed approach as a method of mass production. Filling the targets quickly enough is a problem with tritium inventory whereas the rapid processing might not produce a sufficiently smooth target surface.
Ron Miller continues to work on his action items, concentrating on the evaluation methodology and cost algorithms. He has been working on curve fitting the provided target gain curves. Determining the cost of electricity remains an important parameter as noted in the crisis in California. Ron highlighted that the Generation III fission plants are quoted as being capable of delivering electricity at 35 mills/kWhr and pebble bed, gas cooled fission plants could be as low as 30 mills/kWhr in small unit sizes. Ron quoted an October 2000 ANS talk by a utility official who said that buying a large 1200 MW unit would depress electricity prices when unit was brought on line. This official preferred small unit sizes, even if the COE was more expensive.
Wayne Meier continues to make progress on his HI driver model, with more parametric curve fits to the NRL gain data provided.
Off Normal Event Assessment
Don Steiner said he could not attend the next meeting but would provide presentation material to Dave Petti. Don has been identifying off-normal events such as reduced yield and no yield target/driver cases. He is also estimating the likelihood and the consequences of the off-normal events. He is working with Dan Goodin on the target system events and John Sethian on the KrF laser driver and beam events.