where δφ is the virtual displacement (test function) that vanishes
on Γd , and T is the nominal traction resulting from the contact interaction on the lubricated boundary Γl . As discussed below, the
Reynolds equation, which governs the lubrication subproblem, is formulated in the deformed configuration, and so is the corre- sponding traction exerted on the solid. Accordingly, the surface traction term in (4) is transformed to the deformed configuration