Numerical Investigation of Squeeze Flow Between Two Parallel Disks of Bi-viscous Fluid

This study concerns a numerical test of squeeze flow for bi-viscous fluids defined around a yield stress which makes it possible to represent the Newtonian and Bingham fluid in limiting cases using the lubrication approximation. Commercial fluid dynamics software, ANSYS Fluent 19.R3, was used to solve the squeeze flow as a function of Reynolds and Oldroyd numbers. For viscous Newtonian fluids, the majority of studies have either provided exact solutions for velocity and force or have conducted experimental investigations. For Bingham fluid, most numerical studies are focused on the “nondifferentiable” expression of the constitutive-equation using the finite difference method. In this study, the influence of Reynolds-number (inertia effect) on the radial velocity and pressure of a viscous Newtonian fluid is examined. However, the study focuses on the influence of the Oldroyd number on the radial velocity of Bingham materials as a limit case related to the biviscosity model and on the identification of sheared and unsheared zones (rigid zone) within the squeeze test between circular disks.