Development of He-cooled divertors for fusion power plants

Within the framework of the European power plant conceptual study (PPCS), different helium-cooled divertor concepts based on different heat transfer mechanisms are being investigated at ENEA Frascati, Italy, and Forschungszentrum Karlsruhe, Germany. They are based on a modular design which helps reduce thermal stresses. The design goal is to withstand a high heat flux of about 10-15 MW/m2 a value which is considered relevant to future fusion power plants to be built after ITER. It is an additional challenge that many physical and material-specific factors of the future reactors are unknown. A first design approach and the state of the art of divertor development shall be subject of this report. (author)