Lubrication of porous solids in reference to human joints

Abstract

A simple mechanical model which has some features in common with load bearing human joints is described. The normal approach of two plane surfaces, one of which is covered with porous material is analysed. The gap between the two surfaces is filled with micropolar fluid to represent a particulate suspension (i.e, synovial fluid) as lubricant. The poresize diameter is so small that only the suspending medium,i.e, the viscous fluid enters into the porous matrix due to the filtration action. The problem has been solved separately in two regions; flow of viscous fluid in the porous matrix and the squeeze film lubrication with micropolar fluid as lubricant in between the two approaching surfaces along with suitable matching conditions at the porous boundary. Several interesting results have been brought out. Agreement with available experimental results and the computational results presented, herein, is quite good.