Numerical investigation on a jet pump evolving liquid lead for GEN-IV reactors

•The design of the LFR pumps allows for an easy removal of the pump from the reactor vessel.•The use of a jet pump in LFRs increases natural circulation when pumps are off with respect to other designs.•The design of a liquid lead jet pump as primary pump for ALFRED has been developed.•The CFD validation has been done using experimental data for water.•A parametric analysis has been performed to obtain an optimal configuration.

Heavy-liquid metals, such as lead and lead–bismuth eutectic, are promising candidates as coolant for advanced GEN-IV fast reactors as well as for Accelerator-Driven Systems. The advancing knowledge of the thermal-hydraulic behavior of these fluids leads to explore new geometries and new concepts aimed at optimizing the key components of a GEN-IV reactor for these fluids. In this paper, a theoretical and computational analysis is presented of a jet pump evolving liquid lead as primary pump for ALFRED (Advanced Lead Fast Reactor European Demonstrator). The jet pump is modeled with a 3D CFD code (FLUENT) and at design operating conditions. The analysis shows that a jet pump could be a viable solution for ALFRED (at least from a thermal-hydraulic point of view), albeit some technological issues remain to be fully addressed.