Researchers Realize Goal of Predicting Friction from Measurable Properties of Liquid Lubricant

Achievement date: 
2014
Outcome/accomplishment: 

Researchers at the Center for Compact and Efficient Fluid Power (CCEFP), an NSF-funded Engineering Research Center (ERC) headquartered at the University of Minnesota, have recently defined the measurable liquid-lubricant properties necessary to predict friction.

Impact/benefits: 

The approach used by the ERC researchers finally permits achievement of what has been an elusive goal of researchers in elastohydrodynamic lubrication since the 1960s. The prediction of friction from measureable properties will allow the engineering of liquids for reduced losses from mechanical energy.
Explanation/Background: 

The predictions are made possible by using dimensionless numbers that delineate various friction regimes. Past work, which employed fictitious properties derived from measurements of the friction, was not predictive. The recent CCEFP research has defined the necessary properties that make friction predictions possible, and the prediction capability has been experimentally validated (see figure).