Experimental characterization of the flowline of a lithium film formed using an electromagnetic thruster for a RAON prototype charge stripper

Abstract

This paper describes the variable optimization of a lithium charge-stripper device for the Rare isotope Accelerator complex for ON-line experiences (RAON) and the experimental characterization of a lithium film formed for the charge removal of uranium using a magnetohydrodynamic liquid metal circulation system. To this end, liquid lithium charge stripper was fabricated to form a thin lithium film flow through collisions between a liquid lithium jet and a planar deflector. The flow characteristics of the lithium film were analyzed through simulation and waterjet experiments in terms of the liquid lithium film thickness. To circulate the liquid lithium, a mechanically safe electromagnetic thruster with precise pressure control was designed by analyzing its electromagnetic and hydraulic parameters through finite element simulation. The analysis of the geometrical arrangement of the permanent magnet and input current of the thruster revealed that compared to existing electromagnetic thrusters, the nominal input current of the newly-constructed thruster was reduced to 57% and its weight reduced to 6%, while facilitating easy maintenance. The optimized nozzle diameter and angle of the lithium charge stripper was 0.7 mm and 34°, respectively. Further, the formation of a 22-µm thick liquid lithium thin film required to obtain the 79+ charge state of uranium was confirmed at an input current of 107 A.