Squeeze lubrication between soft solids: A numerical study

Squeezing a lubricating film between viscoelastic solids is a process with many applications, ranging from biomechanics to industrial engineering. The problem is addressed by means of an innovative numerical strategy coupling a finite difference solver for the lubricant fluid dynamics and a Boundary Element approach, which provides the deformation field in the solid. Results show marked differences compared to classical elasto-hydrodynamic lubrication (EHL): Pressure and film thickness depend, in fact, on the material viscoelastic relaxation, peaking at the two edges of the lubricated contact area. This implies, also for the minimum and central thickness values, time-dependent trends that significantly deviate from EHL solution and, thus, point out the necessity of accounting for the actual viscoelastic rheology of the lubricated solids.

Automated summary

Squeezing a lubricating film between viscoelastic solids has various applications in fields ranging from biomechanics to industrial engineering. By using an innovative numerical strategy, the study shows that pressure and film thickness depend on the material's viscoelastic relaxation, peaking at the two edges of the lubricated contact area, which deviates significantly from the classical elasto-hydrodynamic lubrication solution and highlights the importance of considering the actual viscoelastic rheology of the lubricated solids.