Theme 03 ChitID 03.001 Richard Buttery 6/08/2009 11:07 Theme 03 Given US consensus that an extra facility(s) is needed before DEMO can be built, the priority of this week should be to agree that the US should proceed with this, and start to scope out the optimum set of missions for this facility. ChitID 03.002 Richard Buttery 6/08/2009 11:12 Theme 03 Given US consensus that an extra facility(s) is needed before DEMO can be built, the priority of this week should be to agree that the US should proceed with this, and start to scope out the optimum set of missions for this facility. ChitID 03.003 Clement wong 6/08/2009 11:28 Theme 03 Based on Mike's presentation this morning: It would be appropriate to strengthen the identification on the unknowns on PFC surface material evolution and behavior from the DT products, namely alphas and neutrons. We know potential damages from alphas, like the W-blisters and W-fuzz, but this may be the tip of the iceberg. We have to get ourselves and the community to pay attention to these potential surface material damage contributors. We have to organize our modeling and experimental efforts accordingly. ChitID 03.004 Rob Goldston 6/08/2009 11:32 Theme 03 The integrated testing thrust is also parented by Theme 2. The issue of compatibility with the core plasma needs emphasis. In terms of additional pillars maybe the main one is the solution of off-normal events from Thrust 2. It should also be emphasized that the integrated testing needs to be done with long pulses, hot walls, and high power. ChitID 03.005 Rob Goldston 6/08/2009 11:32 Theme 03 The temperature limits for Li calculated in terms of evaporation rate does not take into account the probability that the evaporated Li gets into the plasma, and the impact on the plasma of the Li that does enter the plasma. Results from FTU and NSTX (and elsewhere) suggest that 400C may be too low a limit to set for liquid lithium. ChitID 03.006 Rob Goldston 6/08/2009 11:39 Theme 03 This was a very nice, high-level, understandable talk. Impressive job integrating this story together into an understandable overall picture. - Rob ChitID 03.007 Tony Taylor 6/08/2009 11:40 Theme 03 Topic Transient heat flux (ELMs) The last figure shows a diagram of the program progressing from present devices to demo. It was made clear during the presentation that the impulisive heat flux (from ELMs) is a much more serious problem than the steady state heat and particle flux. It was further stated that the "ITER solution" is not likely credible for DEMO. It is my opinion that if these statements correctly represent the tehnical status, then elimination or reduction of ELMs should be the major element of a thrust in this theme -- a new thrust or the key element in thrust 10 or thrust 11. ChitID 03.008 Clement Wong 6/08/2009 11:45 Theme 03 Mike emphasized the issue of quantifying the FW heat flux for ITER. ITER is now designing the FW blanket/shield at heat flux of 1-5 MW/m2, which is very different from the 0.5 MW/m2 that conceptual reactor designers have been using. Presently, the 5 MW/m2 for ITER at certain locations is from the parallel heat flux. We do have to understand much better on the contribution of blobs and parallel heat flux, which may not have been emphasized in our thrusts. The first wall heat removal for DEMO is very different from the divertor. Presently, we are optimizing our first wall design to ~0.5 MW/m2 with helium coolant and we are having problems already in balancing the temperature limit of <550 C for RAFS steel versus acceptable pumping power for the helium coolant. We will definitely degrade the reactor performance if a large section of the first wall will need to be designed for 1-5 MW/m2. The leads to the necessary emphasis of research needs in these areas in our thrust descriptions. ChitID 03.009 Martin Peng 6/08/2009 11:59 Theme 03 The theme description makes references to the need to carry out research in PMI in a full fusion nuclear environment, but says that one must first find integrated solutions in non-nuclear environment before testing the solutions in a full nuclear environment. This logic contains the weakness of a substantial likelihood that the non-nuclear solutions fails to function in a full nuclear environment. This logic is further not consistent with the statement in the Greenwald panel report regarding PMI, which included the condition of "under very high neutron fluence" in defining the R&D needs. The creation of a full fusion nuclear environment to enable the required full range of PMI research, including the partial non-nuclear solutions research, therefore should be a key element in the research thrusts included in Theme 3. ChitID 03.010 richard nygren 6/08/2009 16:53 Theme 03 A. Add figure(s) in Chapter 3. There were several excellent figures in presentation. ChitID 03.011 richard nygren 6/08/2009 16:54 Theme 03 Specify in "links" which items share common concerns AND differentiate where the impetus or responsibility also of interest in this thrust is assumed to be covered preferentially in another thrust. ChitID 03.012 richard nygren 6/08/2009 16:55 Theme 03 Make clear where concern about neutron effects is liked to the need for integrated testing in an nuclear test stand or D/T facility.