Elastohydrodynamic lubrication abbreviated EHL is a lubrication mechanism encountered in non conformal machine element contacts, like gears and rolling element bearings. This means concentrated contacts in which high pressures occur that deform the contact bodies in a significant manner.
If these contacts move relative to each other and a lubricant is present, the lubricant may be drawn into the contact area. Due to the squeezing of the lubricant into the zone of high pressure the lubricant may be compressed and form a film seperating the surfaces.