Detailed design of a solid tungsten divertor row for JET in relation to the physics goals

作者：Mertens Ph^*

来源：Physica Scripta, 2011, T145: 014002.

DOI：10.1088/0031-8949/2011/T145/014002

In the framework of the ITER-like wall (ILW) for the JET tokamak, a divertor row made of bulk tungsten material was developed for the position where the outer strike point is located in most of the foreseen plasma configurations. In the absence of active cooling this represents a formidable challenge: such plasma-facing components (PFCs) are fully metallic and subject to much higher electromagnetic loads than commonly encountered. The basic geometry of the divertor is similar to the previous one, made of carbon-fibre composites. The present paper stresses the wide span of different aspects that contributed to the conceptual and detailed developments, in relation to the physics goals. They are presented with an emphasis on the results of thermal and electromagnetic models and of their validation in electron (JUDITH-2) and ion-beam (MARION) facilities. Several operational constraints arise from the absence of active cooling and from the segmentation; it will force the exploitation to be driven by this PFC to a large extent. Recommended scenarios encompass sweeping procedures over several thermally insulated stacks and an energy deposition below 60 MJm-2 that can be obtained with impurity seeding. Significant progress in the preparation of PFC-compatible divertor plasma was made in the last physics campaign before shutdown.

• 出版日期2011-12