Modeling results for mass production layering in a fluidized bed

A fluidized bed has been proposed as a layering device for the mass production of inertial fusion energy fuel pellets. During this layering process, the frozen deuterium or deuterium–tritium mixture filled into a hollow capsule (about 2–4 mm in diameter) is redistributed leading to a fuel layer of uniform thickness on the inside of the fuel capsule.Several physical processes have been identified to interact with each other to influence the outcome of the layering process in a fluidized bed, which needs to fulfill symmetry requirements of the fuel layer thickness, smoothness and surface damage requirements of the outside target surface and must be able to produce a large number of targets (500 000 per day). This work describes the development and use of numerical tools to conduct a trade-off study focusing on the influence of different flow conditions of the fluidizing gas on the total layering time, final layer uniformity and outer surface damage.