Magnetohydrodynamic squeeze film characteristics between parallel circular plates containing a single central air bubble in the inertial flow regime

In this paper, the magnetic effects on the Newtonian squeeze film between two circular parallel plates, containing a single central air bubble of cylindrical shape are theoretically investigated. A uniform magnetic.field is applied perpendicular to the circular plates, which are in sinusoMal relative motion, and fluid flbn inertia effects are included in the analysis. Assuming an ideal gas under isothermal condition for an air bubble, a nonlinear differential equation for the bubble radius is obtained by approximating the momentum equation governing the magnetohydrodynamic squeeze film by the mean value averaged across the.film thickness. Approximate analytical solutions for the air bubble radius, pressure distribution, and squeeze film force are dewrmined by a perturbation method for small amplitude of sinusoidal motion and are compared with the numerical solution obtained by solving the nonlinear differential equation. The combined effects of air bubble, fluid film inertia, and magnetic field on the squeeze, film force are analyzed. © 1999 ASME.