An analytical study of the squeezing flow of synovial fluid

The problem of the squeezing of a fluid film with a complex rheology is studied. The fluid is represented by the Phan-Tien and Tanner (PTT) constitutive equation. The goal of the paper is to develop an analytical approach which allows one to describe and quantify this process, which is often present in classical lubrication problems, but particularly in human joints. The present approach can potentially supplement time-consuming and costly purely numerical methods which are also susceptible to misleading artifacts. A parametric study reveals the effect of fluid elasticity compared to viscous effects and some explanation is suggested as to their possible links with joint diseases.