Parametric Analysis of Oscillating Squeeze Film Using a New Dimensionless Parameter

Abstract

A comprehensive mathematical model has been established including a new dimensionless parameter Ω to investigate the effects of surface roughness and permeability of rubber block on leakage flow rate and hydrodynamic force generated in fluid film between annular porous rubber block and oscillating annular rigid block.  The modified Reynolds equation, Laplace equation and governing equation for three-parameter viscoelastic model are solved simultaneously to obtain pressure developed in fluid film between the mating surfaces as well as in the porous matrix. It is seen that with the increasing standard deviation of surface height of rubber block, hydrodynamic force developed in thin fluid film increases whereas leakage flow rate decreases. Combined effect of permeability of rubber block and frequency of oscillation on hydrodynamic force and leakage flow rate has also been studied. Based on the present analysis it can be suggested that surface roughness of rubber block is advantageous for wet clutches, bearings, non-contacting face seals due to good load bearing capacity and optimal selection of permeable rubber material is necessary in engineering applications.  

Keywords: Fluid film lubrication, surface roughness, hydrodynamic force, leakage flow rate