A Comparative Study of Water Lubricated Journal Bearings with Rotating and Stationary Recesses for Fuel Cell Compressor

摘要

This paper presents a stability investigation of the water-lubricated journal bearings with rotating or stationary recesses. The dynamic coefficients and stability threshold speed of the bearings are numerically calculated by solving the turbulent Reynolds equation by using FEM. The theoretical results show that the bearing with rotating recesses possesses periodical dynamic coefficients and stability threshold speed whose frequency is equal to the product of the recess number by the rotation frequency. The rotating of the recess decreases the bearing stability, especially at low rotating speed. In addition, the recesses number has different influence on the stability of the two bearings. The validity of the theoretical analysis was verified by the experiments on the built compressor.