Liquid Lithium Target for Neutron Generation

At the University of Illinois, a compact, liquid lithium loop has been developed and tested. The compact, yet scalable, loop is comprised of a stainless steel trench system embedded with heaters and cooling lines, and was designed to handle large heat and particle fluxes in neutron generators as well as fusion devices. Lithium flow is driven through the sole use of TEMHD. The flowing lithium will keep a fresh, clean surface, allowing Li-7(d,n) reactions to occur, as well as enhance the deuterium adsorption in the fluid. The enhanced deuterium absorption helps by increasing the total neutron output. Previous work has shown that using a tapered trench design allows for an increase in fluid velocity at the particle strike point. Initial experiments, where a temperature gradient was imposed using the embedded heaters and helium cooling, peak velocities of 16 ± 4 cm/s were observed. For heat fluxes greater than 10 MW/m², COMSOL fluid models have shown that sufficient velocities (~100’s cm/s) are attainable to prevent significant lithium evaporation. Current work is aimed at determining the necessary velocities and geometry to prevent dryout as well as the system’s neutron output. The early results and discussion will be presented.