Compressive squeeze flow of generalized Newtonian fluids with apparent wall slip

The compressive squeeze flow is encountered in various processes like compression molding and in rheometry. It involves a complex deformation field driven by both shear and normal stresses. Here the flow and deformation field generated during the compressive squeeze flow of generalized Newtonian fluids, subject to wall slip, was analyzed using both numerical simulation based on the 2-D Finite Element Method and the 1-D analytical model, which is based on the lubrication assumption. The agreement between the analytical and numerical solutions deteriorates wit increasing Navier's wall slip coefficient and the increasing yield stress value of the viscoplastic fluid. The lubrication assumption is valid under various squeeze flow conditions but numerical analysis in conjunction with experimental studies are necessary to determine the ranges of material parameters and operating conditions for which the lubrication assumption is valid.