Energy savings and improved precision with adjustable hydrodynamic bearings

For over 40 years, organizations in the USA and Europe have postulated that savings of billions of dollars could be available with improved practices in lubrication research, education and application. Such initiatives were presented when concerns over energy use and global warming were not the mainstream topics they are today. This paper outlines some of these claims and discusses developments in hydrodynamic journal bearings that address the issues, deliberately or otherwise. In particular, work done by the author and colleagues, and other groups internationally, have shown that the concept of pro-actively adjustable bearings offers both improved energy efficiency and greater precision of location. These aspects are especially advantageous in long running applications in terms of saving energy, and at lighter loads where conventional fluid film bearings are prone to instability. The centre of rotation position can also be maintained, or moved as desired, irrespective of loads or changes in load