Some of us have been at Kyoto for a US-Japan workshop on reactor design study. There were participants from EC and China. I will like to summarize to you on some of the design proposals given by other participates:
The EC gave their work on theSEAFP. The structural material was V-alloy (V-15Ti). The breeding material is Li2O with 70% enrichment. They claim that they did calcuation which shows that, with 70% enrichment, they can obtain sufficient tritium breeding without the use of Be. (I ahve some problem with that. Based on my knowledge, 20 to 30% enrichment is the optimun enrichment without using Be. By using 70% enrichment, the N,N' reaction is reduced, and tritium breeding will suffer. Laila, can you comment on this?) Li2O is enclosed within V structure, and He purge is used for tritium recovery.
No work on the compatibility between He coolant and He purge with V-alloy was done.
Knight gave a presentation on the LAR design. Most work is on the physics, with minor emphsize on the engineering. There was no report on the engineering issues associated with the divertor.
Inoue gave a talk on the demo design. The structural material was 316SS.
The dream-2 design was given by many talkes. The structural material for dream-2 is SiC composite, with He as the coolant and Li2O is used for the breeding material. (Sounds familiar?) The thermal conductivity of the SiC used is between 15 w/m-C to 60 w/m-C for the divertor. There was no justification of the thermal conductivity values.
Both Ueda (with Seki) and Kohyama reported the R/D activities in Sic, and in material including SiC, in Japan. There are some reports on thermal conductivity, on mechanical properties, on radiation stability, on joining. It is obvious that the stage of developement of SiC for fusion is still at a very early stage.
Sagara reported the design for FFHR. Flibe was used for the breeding material, with 40% volume of Be in the blanket. The total blanket and shield thckness is only 1 m, and they claimed this is enough for breeding and shielding. The material used for shielding is 70% 9 Cr steel and 30% B4C. The blanket is 30 cm thick while the shield is only 60 cm thick. Again, I have some problems with the design.
The Chinese presented some work they did on the hybride reactor and VNS. The important point I got is the size of the problem they are having. They estimated that, by the year 2050, they will need 1500 GW of additional power generating facility. Thus, they will need 30 full size commercial reactor every year! Since the life time of a commercial reactor is limited to 30 or 40 years, they will need like 40 commercial reactor every year. This is scary.
Nobody has addressed and designed for the requirement of a stabilize shell within the blanket.
With some discuss with Najmabadi, I firmly believe that we have done a more self consistent design than anyone else, at least based on the presentations gave in this workshop. Not only that, we appears to be pace setters, which developed some new concepts and other people would follow the concept we have proposed.