Study of a Ferrofluid Lubricated Hydrodynamic Journal Bearing System by the Magnetic Fieldwith Magnets

This study used ferrofluid as bearing lubricating fluid and added a magnetic field outside the bearing to test the effect on the oil bearing. The experimental results showed that magnets arranged by different methods can all increase the instability threshold of the oil bearing. Especially, the magnetic field formed by eight magnets has the optimal effect. The whirl speed and the whip speed can be increased to 4480 rpm and 5268 rpm.