ARIES Program
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ARIES-Pathways Project Meeting Minutes

4-5 September 2008

University of Wisconsin - Madison, Madison, WI

Documented by L. Waganer

Organization ARIES Pathways Project
Boeing Waganer, Weaver
General Atomics Turnbull (Phone-in)
Georgia Tech  
PPPL Kessel (phone-in), Meade
UCSD Dragojlovic, Malang (Phone), Najmabadi, Raffray, Tillack
UW-Mad El-Guebaly, Kulcinski, Santarius, Sawan, Henderson, Marriott, Zenobia (student), Bonomo, Boris (student), Schuff (student)

Ref: Agenda and Presentation Links: Meeting Agenda


Welcome - Laila El-Guebaly welcomed the ARIES team to the University of Wisconsin - Madison and covered the logistics of the meeting. The University provided snacks and refreshments for the group. Les Waganer reviewed the meeting agenda.

ARIES Pathways Plans - Farrokh Najmabadi noted three important events on our immediate horizon (FESAC meeting, TOFE Conference, and publishing the Pathways Interim Report). To make sure that the project was properly prepared for those events, this meeting was structured to be a workshop format that reviewed the interim report, fusion power subsystems TRL assessment, and utilization of the revised systems code.

The next most immediate project effort will focus on completing the interim report, finalizing the TOFE papers, and preparing the FESAC TRL talks by Tillack and a Boeing person. Tom Weaver is preparing that draft presentation, which was previewed at this meeting. Dale Meade said the next FESAC meeting is scheduled for November 6-7, 2008 in Gaithersburg, MD. The FEASC agenda has not been published but it is thought to include an introduction to TRL methodology, an Alternate Panel report, and the OFES Bold Plan for Fusion that will be presented to Congress in March 2009.

Rene Raffray mentioned there will be an International HHFC Workshop on "Readiness to Proceed from Near Term Fusion Systems to Power Plants" held on December 10-12, 2008 in San Diego. Rene Raffray is one of the organizers.

Concluding the ARIES Pathways Interim Report and TOFE Presentation - Mark Tillack

(Action items are underlined)

Mark Tillack reviewed his progress in putting together the current status of the program into the interim report. Technical Working Groups (TWGs) were formed to help define the current status and future R&D needs for certain technical areas necessary to develop from the ITER technology base to what is needed to begin design and construction of Demo. The Technology Readiness Level methodology was adopted from NASA, DoD, and DOE to help quantify the current technology levels. The area of most concern is being able to explicitly define the technologies required for Demo and the demonstration and testing environments (laboratory, relevant, and operational) in the fusion vernacular. It was suggested that all primary interim report authors re-read the entire interim report for correctness and consistency. All TRL contributors should provide a justification for the TRL assessment. Dale Meade asked if the EU (or Japan) has a similar technology assessment. Rene will be at SOFT conference and can determine if such a methodology exists in the EU.

On "Development of TRL" slide, this slide should emphasize that this is how requirements for development and testing facilities are determined. Farrokh and Mark will collaborate on this slide.

On slide, "We adopted" the TRL 9 should indicate this is for Demo or a commercial plant. We need to decide which is appropriate.

Les Waganer suggested moving GAO slide ahead of the two slides that describe TRL levels.

On slide #3, Example TRL: Heat and Particle Flux, broaden heading for right hand column from "Facilities" to "Program Elements". Also clarify that the integrated large facility is not ITER.

On slide #4, Evaluation of Readiness, Laila should clarify Waste Management entries.

On slide #5 Current Status, eliminate second graph and concentrate on first one. Scrub all TRL assessments and make sure we identify the justification. May need to increase size of descriptors in first column to clarify meaning (carry over to next chart). Indicate Plasma Materials Interface is included in the second line item, if it really is. Don Steiner, Laila El-Guebaly, Phil Sharpe, and Lee Cadwallander should agree on Waste Management values. Add a key to identify the meaning of different colors used in the slide.

Do not use ARIES AT and instead use advanced tokamak.

On the ITER contributions slide, use a different color other than yellow to indicate ITER's contribution. Need to further scrutinize ITER's contributions.

On the "Major Gaps Remain" slide, there was discussion about moving the CTF contribution earlier to eliminate any gaps, but it was concluded it may be appropriate to keep the remaining gaps to emphasize work to be done. Add a color key to indicate the Orange color means the use of large integrated facilities to help mature the technologies to an "operational, integrated" state. Also it would be better to include "CTF" in quotations marks to indicate that it is a hypothetic generic facility with no specific mission definition at this time or replace CTF with "Operational Integrated Test Facility". Suggest we add a bullet to indicate that we are trying to establish consensus that a TRL of 9 represents validation either in Demo or the operational power plant.

Need to add a summary slide.

Overall, the TOFE talk and FESAC content are very good with some minor modifications to some slides. Perhaps we should consider delaying publishing the report until we have better substantiation on TRL levels and feedback from the community (TOFE and FESAC) about the TRL process.

Neutron Testing: What are the Options for MFE? - Laila El-Guebaly

(Action items are underlined)

Laila El-Guebaly examined the existing materials testing facilities with regard to determining property changes with appropriate irradiation for the fusion environment. Berkeley has the only 14 MeV materials irradiation facility in the US and it has a volume of several cm3. Other non-fusion irradiation facilities can be used for some material characterization. However, NRC will not license a fusion device unless components are fully tested in a relevant fusion environment to assess multiple, synergistic effects (TRL 5 or 6). ITER will not be a relevant environment as it will not produce a high fluence environment. A CTF facility is required to achieve a relevant environment with sufficient volume to test components. Jerry Kulcinski noted that it is necessary to have all relevant materials in the test environment to obtain synergistic effects (a single blanket test module in a largely non-blanket environment is not sufficient to measure critical parameters, such as tritium breeding and diffusion). Dale Meade mentioned it is very important to fully define how the test parameters are measured in the experiment.

Laila provided data and examples of property degradation with irradiation, which emphasized the need to have the irradiation materials database. She also provided the test volumes of existing DOE facilities. Laila concluded that experiments in existing facilities would not certify mockups for CTF. Many experiments are not designed to test multiple effects. She then described the key features necessary for CTF to qualify all the components for Demo. CTF is an essential element of the proposed US roadmap to Demo, whereas EU goes directly from ITER (and IFMIF) to Demo. Some collaboration with other worldwide testing facilities is possible if they upgrade their programs to include multiple effects and stronger neutron sources. Alternatively, a cost-effective approach is to build an integral experiment at UW with relatively inexpensive 14 MeV intense neutron source.

TRL Assessment of Fusion Power Systems - Rene Raffray

(Action items are underlined)

Rene Raffray said his goal was to develop TRLs for key power subsystems consistent with the FESAC Theme C, "Harnessing Fusion Power". He described five key issues to the Theme C: fuel cycle, power extraction, materials science, safety, and RAMI. He would build on existing ARIES TRL efforts, but focus more on the power subsystems and components, principally the blanket, first wall (FW), divertor, and shield. Suggest expanding list to include some of the other plasma facing components such as the RF antennas, launchers, and some instrumentation.

Near the beginning of talk, explain what is meant by developing, testing, and validation.

On slide with flow chart, need to clarify what is meant by Power Control System - Is it Plasma Control or Integrated Plant Control or something else?

Slide 8 with blanket functions: Safety, keep the tritium inventory as low as possible in the blanket. Also delete the phrase "unrestricted release".

On TRL tables, remove column "TRL function". On TRL of 5, suggest adding mention of maintenance demonstration. On Slide 14, TRL of 7, suggest broadening "heat recovery and tritium extraction" to "all interfacing systems".

When discussing ancillary equipment on Slide 16, suggest adding "mass transfer and tritium transfer.

On Second Level TRL definition, TRL 3, Slide 17, replace 2-D neutronics with 3-D neutronics.

On all TRL tables, suggest changing right hand column from "Facilities" to "Program Elements".

Les Waganer suggested broadening the mention of integrated effects to include "structural and maintenance" (many locations).

Consider moving fission/neutron source from level 4 to level 5 (not sure if in first or second level TRL tables. I think is really is second level.). [Les' belated comment: Remember that TRL of 4 is a lab environment, whereas TRL is a relevant environment. We need clarity on these environments. They may be different when we are talking about coupon testing as compared to component testing.]

First and second level TRL 6 descriptions, title for this level should read:" in a relevant environment". Also in TRL 7 descriptions, title for this level should read:".. in an operational environment".

The general consensus was that this was excellent work with a lot of useful technical information and insight. Laila suggested not presenting the DCLL case as it might be too detailed for FESAC discussions. Also, the FESAC committee may be more interested in a plasma-related TRL discussion.

Utilization of ARIES Systems Code - Zoran Dragojlovic

(Action items are underlined)

Zoran Dragojlovic began his talk by describing the improvements in the revised ARIES Systems Code (ASC) and how the upgrades and results would be communicated to the fusion community. He described the rationale for the code improvements and increased capabilities. It should be noted that the geometry modeling in the code has been validated against the CAD geometry. Note how the code has been utilized to examine the entire trade space rather than parametric searches about an optimum design point. The Q noted on page 5 should be labeled as plasma Q.

On page 9, Zoran began to use graphs to display the results of all the points examined. He arranged the lower scoring points to overlay the higher scoring points. Thus it was difficult to understand the meaning of all the results. The data points that lay near constraint boundaries had anomalous behavior as compared to the normal trends. So a lot of time was spent trying to understand the behavior trends. It was suggested to investigate other display forms to better convey the resultant trends.

Starting at page 12, Zoran used color coding to display results for three different heat fluence levels. It was suggested that the color coding and abscissa labeling on all charts be normalized to eliminate confusion. These charts also showed anomalous behaviors near the constraint edges - need to understand what is happening there.

On page 17, the 3-D charts were not conclusive with the limited number of points used. Suggest adding more data points (double the number?) to clarify trends and eliminate false interpretations. Add COE on some missing abscissas labels.

Farrokh suggested tightening up the net electric power limits from ± 10% to ± 2.5%. Not sure if that suggestion was adopted?

We also need to clarify and perhaps change the plasma radiation fraction from 75% used in these calculations to 90% as used in ARIES-AT.

On page 25, Recommendations for Optimal Design, suggest adding with 8 MW/m2 heat flux on divertor. Also suggest eliminating the ARIES-AT row as it has different assumptions than the calculated results. Dale Meade suggested that the code might be rerun with ARIES-AT parameters. Suggest running cases for 10 MW/m2 with a range of divertor radiation fractions to see if this parameter has a significant effect.

Using the DCLL parameters, fewer operating points survived the physics and engineering screening filters. This is primarily due to the higher primary coolant pumping powers. Only the 16 MW/m2 heat flux cases passed the engineering filters. Suggest checking pumping power assumptions and modeling, impurity levels with DCLL case, and widen the plasma Q to 5 or 10. Examine results along constraint boundaries. Run more cases for DCLL. Try to recreate the ARIES-AT case. All the LiPb/SiC cases were at a LSA = 1, but the DCLL case should be at a LSA=2, meaning the DCLL COE will go up by ~25%.

At the beginning, it should noted that all COE results were shown with 2008$.

To prepare for TOFE, suggest adding intermediate data points to increase the resolution for the 3 D plots.

Impact of Technology Readiness Levels on Aerospace R&D - Tom Weaver

(Action items are underlined)

Tom Weaver previewed his draft aerospace TRL presentation he is preparing for Dr. Whelan, Boeing Chief Scientist, to give at the FESAC meeting in November. Tom acknowledged that he had too many slides, but wanted to get feedback on which ones to cut. He should allow about 2 minutes per slide for about 15 slides total. Les Waganer noted that Boeing generally does not do basic research, but matures basic research obtained elsewhere as applied research to mature new technologies sufficiently to apply on existing and new product lines. NASA and DoD use TRLs to help them gauge if the proposed technologies are sufficiently mature to pose minimal implementation risk.

What are the integration issues associated with new technologies? Les Waganer noted that Boeing also uses TRLs to mature their internal tools and processes.

AirBorne Laser (ABL) flight demonstrator is very analogous to the fusion Demo in scope, complexity, number of suppliers, and cost. But limit the number of slides on this subject.

Minimize the acronyms and define those used.

Slide on TRL 6-7 transition highlights a common problem to all.

After Summary slide, add a slide called, Reference that has a list of TRL references and information sources.

Meeting Wrap-up and Future Plans - Farrokh Najmabadi

The action items discussed are generally contained in the prior text.

Dale Meade confirmed that the present date for the FESAC meeting is November 6-7 in Germantown, MD. Check FESAC website for date confirmation and agenda updates. Mark Tillack and Tom Weaver should continue to prepare their TRL talks.

The next project meeting will be held at USCD in San Diego, tentatively on 1-2 December. Les Waganer will poll the team to determine if this date is acceptable.

[Revised] The next call will be on Thursday October 9, at 9:00 PDT.

Dale Meade should collaborate with Ken Schultz on the composition of the Pathways Advisory member list.