Theory, design and CFD analysis of a multi-blade screw pump evolving liquid lead for a GEN-IV LFR Nuclear Power Plant

In this presentation, a theoretical and computational analysis is presented of a multi-blade screw pump evolving liquid Lead as primary pump for the reference conceptual design of the Advanced Lead Fast Reactor European Demonstrator (ALFRED). The pump is analyzed at design operating conditions from the theoretical point of view to determine the optimal geometry according to the velocity triangles and then modeled with the 3D CFD code ANSYS CFX. The choice of a 3D simulation is dictated by the need to perform a detailed spatial simulation taking into account the peculiar geometry of the pump as well as the boundary layers and turbulence effects of the flow, which are typically tri-dimensional. The use of liquid Lead impacts significantly the fluid dynamic design of the pump because of the key requirement to avoid any velocity-related erosion phenomenon. Albeit some erosion-related issues remain to be fully addressed, the results of this 3D analysis show that a multi-blade screw pump could be a viable option for ALFRED from a thermo-fluid-dynamic point of view.