A new concept of active hydrodynamic bearing for application in rotating systems

Abstract

Conventional hydrodynamic journal bearings applied to rotating machines are susceptible to some undesired conditions, such as fluid-induced instability, high increase of temperature and load capacity inefficiency. To avoid these conditions, a new concept of hydrodynamic bearing is proposed in which the own bearing motion is considered, thus making possible to change the average velocity of the lubricating oil film inside the bearing. The rotor dynamic behavior as well as the hydrodynamic forces developed in the bearings are initially evaluated through computational simulation, allowing to verify the advantages and improvements obtained through this new bearing concept. The numerical results show that this new bearing is able to avoid fluid-induce instability in the rotating system, in addition to acting on reducing the oil temperature and bearing load capacity. Based on these results, the new concept of bearing represents a promising alternative to improve the performance of rotating machines.