Effective thermal conductivity of a compressed LiTiO pebble bed

Tanigawa, Hisashi; Hatano, Toshihisa; Enoeda, Mikio; Akiba, Masato

In order to elucidate thermo-mechanical behaviour of the blanket with the water-cooled ceramic breeders, the effective thermal conductivity of a compressed LiTiO pebble bed was measured by the hot wire method. The measurement chamber for the thermal conductivity was inserted into a tensile test-apparatus. Under controlled temperature, atmosphere and mechanical loads, the stress-strain property and the effective thermal conductivity of the pebble beds were measured simultaneously. At the temperatures ranging from 673 to 973K, increases of the effective thermal conductivity due to the compressive deformation were confirmed. In addition, it was found that history of the mechanical and thermal loads on the bed affected the thermo-mechanical properties of the pebble bed.