Lead-Bismuth Target Design for Transmutation Reactors

A lead-bismuth eutectic (LBE) target design has been developed to drive the subcritical multiplier (SCM) of the accelerator-driven test facility (ADTF). This paper gives the target design description, the main results from the parametric studies, and the design analysis including physics, heat-transfer, hydraulics, structure, activation, and decay heat removal analyses. The design is based on a coaxial geometrical configuration to minimize the target footprint since the target is installed vertically along the SCM axis. LBE is the target material and the target coolant. Ferritic steel (HT-9 alloy) is the selected structural material based on the current database and the design analyses. A uniform proton beam is employed to perform the spallation process. The proton beam current is 8.33-mA and the current density is 40-µA/cm 2 , which requires a beam radius of 8.14-cm. The beam power is 5 MW and the proton energy is 600 MeV. The beam tube has 10-cm radius to accommodate the halo current. A hemi-spherical geometry is used for the target window, which is connected to the beam tube. The beam tube is enclosed inside two coaxial tubes to provide inlet and outlet channels for the LBE coolant. The coolant channels and the proton beam enter vertically from the top above the SCM. Several design constrains are defined and utilized for the target design process to satisfy different engineering requirements and to minimize the design development time and cost.