1. Resent Breeding Blanket Experiments - CONTENTS - - Objectives - - Resent breeding design at JAERI - - Brief history of FNS blanket experiments - - Resent blanket experiments at FNS

2. Objectives Our aim is to verify the nuclear performances of resent designed DEMO-fusion blanket at JAERI. - Tritium production rate - Activation rate - Nuclear heating rate - Shielding ability The verifications of the blanket nuclear performances mean to obtain the accuracies of the following contents with D-T neutron experiments and the neutron-transport calculation,so-called, benchmark experiment.

3. JAERI suggests the thermal blanket to obtain TBR>1 -Breeding type Thermal blanket type -Breeder 30% over 6 Li-enriched ceramics pebble Candidates: Li 2 O, Li 2 TiO 3, Li 2 ZrO 3 and so on -Neutron multiplier Beryllium pebble -Structure materials Low-activation materials (F82H, SiC and V- alloy) Candidates: F82H, V-alloy and SiC -Coolant materials Candidates: H 2 O and He-gas -Configuration Stratified configuration Resent JAERI breeding blanket design Multiplier BeBreeder Li 2 TiO 3, Li 2 O 600 mm A concept drawing for the DEMO-fusion blanket

4. No thermal blanket nuclear performances has verified. Therefore, Resent FNS works is to verify of the suggested thermal blanket. Fusion Breeding Blanket Nuclear Design Fast blanket 7 Li(n,nt)  Brief history of FNS blanket experiments FNS benchmark experiment Thermal blanket 6 Li(n,t)a + 9 Be(n,2n) Fast blanket type, SUS and nat-Li 2 O 1980s 1990s~ Be, nat-Li 2 TiO 3, nat-Li 2 ZrO 3, V and SiC Thermal blanket type F82H, V-alloy and SiC 6 Li-enriched breeder materials FNS has already obtained the data No verification ~ 2000

5. Resent blanket experiments at FNS - Test assembly - Calculations - Nuclear measurements - Preliminary results - Future works We have started the first-step experiments to verify the 1 st breeder-TPR and the F82H-activation from 2001.

6. Test assembly FNS D-T Target F82H/95-%Li 2 TiO 3 /Be Assembly Li 2 CO 3 - block Detector(NE213) Assembly -50 x 50 x 30 cm -F82H/Li 2 TiO 3 ( 6 Li:95%)/Be assembly surrounded by Li 2 CO 3 and B 4 C blocks D-T neutron conditions -Neutron flux: 1.5 x 10 11 n/sec/mA -Irradiated time: 10 ~ 20 h 200 300  25 Li 2 CO 3 FNS target 1000 F82H 16mm F82H 3mm 6 Li-95% Li 2 TiO 3 12mm Be 31 500 300 200 Cross section view of the test Assembly (Unit: mm)

7. Calculations Code: MCNP- 4B, Nuclear Data: JENDL-FF, JENDL-D and ENDF/B-V (VI) eVkeVMeVTotal 6 Li(n,t)-TPR 1.8E-4 2.5E-53.86E-4 7 Li(n,nt)-TPR --- 4.8E-5 123 F82H (16mm) F82H (3mm) 4 Li 2 TiO 3 (12mm) Be (200mm) 1 2 3 4 Li 2 TiO 3 (12mm) 25 2 5 TPR [Tritium/SN] Energy [MeV] Neutron spectra at each position in the assembly [Unit: Tritium/SN]  10

8. Nuclear measurements Liquid Scintillation Counter for tritium measurement HpGe-detector for activation of F82H Complementary instruments (NE213, U-235 and U-238) F82H (Fe:90%, Cr:8%,W:2%) Tritium  - ray spectrum from the irradiated Li2TiO3 sample  ray spectrum from the irradiated F82H sample [keV]

9. Preliminary results Position from the assembly surface [x10mm] C/E of tritium production rate Exp. error Calc. error Reaction rates and TPR for the each position in the assembly C/E of TPR for the Li 2 TiO 3 position in the assembly

10. Future works FNS has plans Tritium production rate for the following assembly Multi-layers assembly ( 6 Li 40-% Li 2 TiO 3 3-layers assembly) ~2001 Multi-layer assembly + water layer ~2002 Pebbly assembly