多孔質ゴムと剛体面間に形成されるスクイズフィルムに関する研究 : 第 1 報粘弾性連続体モデルを用いた解析

抄録

Squeeze film effect between a porous surface and a rigid surface is investigated as a problem of visco-elastic hydrodynamic lubrication (VEHL). An axisymmetric continuum model is introduced based on a three element visco-elastic model to estimate the deformation of a cylindrical porous rubber block. The coefficients in the visco-elastic constitutive equation are experimentally determined and the deformation is calculated by FEM. To take into consideration the fluid inertia effect in the squeeze film, the approximate solutions for the film pressure are obtained from the Navier-Stokes equation and the continuity equation using the perturbation method. The squeeze-film pressures and forces are measured under the sinusoidal squeezing motion with a cylindrical porous rubber block. The difference between the VEHL solutions and the EHL (elastohydrodynamic lubrication) solutions becomes more marked for a higher frequency of squeeze oscillation due to the effect of viscoelasticity of the porous rubber. Hence, the VEHL solutions correspond better to the measured results and yield a smaller surface deformation of the porous rubber block than the EHL solutions as the frequency of squeeze oscillation increases.