EHD lubrication of point contact
Lubrification élastohydrodynamique

Under load, the contact area increases and becomes elliptical (see figure 8 ). By reducing one of the two surfaces to a plane, the contact is equivalent to a barrel-plane contact, which will have the same elliptical zone and pressure field as the actual contact. The barrel has two main radii of curvature, which we will note R _x in the direction of the bearing and R _y in the direction perpendicular to the bearing.