Development of a flow distributor for the actively pumped open-surface lithium loop

A distributor, producing uniform flow, has been designed, manufactured, and installed onto the Actively Pumped Open-surface Lithium LOop (APOLLO) at the University of Illinois at Urbana-Champaign (UIUC). The anisotropic features of the distributor were determined using a two-step approach utilizing topology optimization routines in COMSOL Multiphysics and the Turing reaction-diffusion system equations. The distributor was then additively manufactured from 316 stainless steel and installed onto the APOLLO Plasma Facing Component (PFC). Good distribution was achieved during experimentation with a variation of 6% – 9% in velocity measured across the distributor outlets. With a flat PFC plate, full wetting was not achieved as flow rivulets were observed on the plate. The inclusion of a 3D mesh structure on the flow plate was shown to promote spreading due to capillary action and complete lithium wetting and coverage of the PFC was achieved.