Squeeze-Film Behavior in Porous Circular Disks

Abstract

The squeeze film behavior between two circular disks is analyzed when one disk has a porous facing and approaches the other disk with uniform velocity. The modified Reynolds equation governs the pressure in the film region while the pressure in the porous facing satisfies the Laplace equation. These equations are solved in a closed form and expressions are derived for pressure distribution, load capacity, and time of approach for the plates in terms of Fourier-Bessel series. It is found that an enhanced value for the permeability parameter diminishes the pressure over the entire disk and also evens out the pressure distribution; however, there is an adverse effect on the load capacity and time of approach. Unlike in the nonporous case, the entire fluid can be squeezed out in a finite time resulting in actual contact of the disks. The porous effects are shown to predominate at very low film thickness values.