Recent improvements of the helium-cooled W-based divertor for fusion power plants

Highlights: ► Three He-cooled W-based divertor design concepts have been proposed for the fusion power plant. ► Thermal-fluid and thermo-structural analyses have been performed. ► Divertor configurations have been optimized based on the design limits of the operating temperature, pumping power and stresses. ► Design adjustments to allow for non-uniform heat flux profiles have been considered. - Abstract: A number of advanced helium-cooled W-based divertor concepts have been proposed recently for fusion power plant applications within the framework of the ARIES Program. This paper summarizes design optimization and improvements of these concepts based on the minimum and maximum operating temperature of the W structure, pumping power and structural design limits. Re-evaluations of all concepts were performed with increased minimum operating temperature of the W structure from 700 °C to 800 °C in order to avoid embrittlement by neutron radiation. Design adjustments to allow for non-uniform heat flux profiles also have been considered. Comprehensive 3D thermal-fluid and 3D finite element thermo-mechanical analyses have been performed considering both elastic and plastic behavior and results are summarized in this paper.