Experimentally Established Correlation between Acoustic Emission Activity, Load, Speed, and Asperity Contact of Spur Gears Under Partial Elastohydrodynamic Lubrication

The application of the acoustic emission (AE) technique to condition monitoring of gears is still at a developmental stage. Understanding the source of AE activity at the gear mesh is fundamental if this technique is to be successfully employed for gear diagnostics and prognostics. This article presents results of an experimental programme that showed a correlation between AE r.m.s. activity and asperity contact under partial elastohydrodynamic lubrication. On the basis of experimental observations, it is postulated that AE can monitor and/or measure the effectiveness of a lubricant in minimizing asperity contact. It addition, it is concluded that two distinct types of AE are associated with the sliding and rolling of meshing spur gears.