1. November 8-9, 2005 1 Blanket Design for Large Chamber A. René Raffray UCSD With contributions from M. Sawan (UW), I. Sviatoslavsky (UW) and X. Wang (UCSD) HAPL Meeting University of Rochester's Laboratory for Laser Energetics Rochester, NY November 8-9, 2005

2. 2 Outline Reference case with large chamber Concluding effort on large chamber for present phase

3. November 8-9, 2005 3 We Have Chosen a Reference Case for the Large Chamber Approach with No Protective Gas Reference Parameters: for no chamber gas and assumed constraint of W T max < 2400°C: -Yield = 350 MJ -R = 10.5-11 m -Rep. rate ~ 5 for 1750 MW fusion (could be higher)

4. November 8-9, 2005 4 W Armor Temperature History and Gradient W temperature at different locations as a f(time) W temperature profile in armor at different times

5. November 8-9, 2005 5 Recap of Blanket Effort for Large Chamber Self-cooled Li blanket chosen out of several options initially considered (including self-cooled and/or dual cooled Pb-17Li, He- cooled ceramic breeder and flibe). -Considerations included performance, simplicity, operating temperature window based on material constraints. Convergence on two cases (with material constraints approved by CTC&MWG): 1.A baseline case with RAFS and no corrosion coating with minimum risk in getting there based on present day material development and knowledge. (focus of study) -Max. FW FS temp. < 550°C -Max. FS/Li interface temp. < 560°C (in blkt); < 575°C (outside blkt) 2.An advanced case with ODS-FS and corrosion coating with higher development risk (and probably higher cost also) as an indication of what could be gained with a more ambitious material R&D program. -Max. FW FS temp. < 700°C Max. FS/Li interface temp. < 800°C

6. November 8-9, 2005 6 Self-Cooled Li Blanket for Large Chamber The design is based on an annular geometry with a first Li pass cooling the walls of the box and a slow second pass flowing back through the large inner channel. Large chamber size led to the division of blanket modules in two (upper and lower halves). Inner Li Channel Annular Li Channel Sandwich insulator: FS-SiC-FS

7. November 8-9, 2005 7 Example Results for Baseline and Advanced Cases with Rep Rates of 5 and 10 Higher Rep Rate -Efficiency about the same -Higher pressure drop and pumping power but still acceptable for rep rate =10 -No effect on max. armor temperature and thermal stresses -However, reduced component lifetime (dpa proportional to rep rate) Choice of rep rate based on above and other considerations (W. Meier)

8. November 8-9, 2005 8 Summary Blanket design, assembly and integration with the vacuum vessel (presented by I. Sviatoslavsky). Neutronics calculations (presented by M. Sawan). Thermal-hydraulics + Brayton power cycle summarized here and presented in more detail at the last meeting. Safety assessment (poster by S. Reyes). We feel that we have developed the concept to enough detail to convince ourselves that it is a credible reference design. Ready for more detailed and fully integrated studies if and when we decide to do a full power plant design study based on the large chamber.