Analysis of lubrication performance and flow field for lead-bismuth bearings considering the temperature-viscosity effect

Abstract

Lead-bismuth bearing performance and dynamic properties are crucial for ensuring the steady operation of lead-bismuth liquid metal pumps since they are one of the primary supporting elements in the lead-bismuth cold fast reactor system. To study and analyze the lubrication performance of lead-bismuth bearings as well as the influence of the viscous-temperature property of lead-bismuth medium on the bearing load performance, a hydrodynamic model based on CFD (Computational Fluid Dynamics) is established. The performance of lubrication comprises addressing the static and dynamic properties of lead-bismuth bearings. The pressure and temperature flow fields of the Lead-bismuth bearing under various working conditions were determined by solving the N-S equation and energy equation. The numerical findings demonstrate a clear strip-like distribution in the temperature and pressure flow fields of the lead-bismuth bearing. The pressure flow distribution in the working and feedback grooves is symmetrical, the temperature flow distribution is isotropic, and the temperature increase is mostly proportional to the rotation speed. As the rotation speed becomes larger, the force in the y-direction, power loss, and leakage flow rate all increase. Bearings with small radius clearance and greater rotation speeds have superior stability than those with big radius clearance and lower speeds. The findings of this paper serve as a point of reference for the study of the viscosity-temperature effect and lubrication theory of lead-bismuth bearings and supply the foundation for subsequent rotor dynamics calculations.