Innovative liquid breeder blanket design activities in Japan

In order to clarify key engineering issues and to enhance key R&D activities for D-T fusion blankets, many design activities on innovative liquid blanket systems are on going as collaboration studies in Japan. Recently an improved long-life Flibe blanket has been proposed, and the self-cooled Li/V blanket design has started. For Flibe systems, much progress has been made on tritium permeation barrier, energy conversion system, free surface designs, and thermofluid loop experiments. For Li/V systems, evaluation studies have proceeded on Be-free nuclear properties and allowable crack fraction on multilayered MHD insulation coatings.