This study investigates the blade coating process of an incompressible Couple stress fluid with pressure dependent viscosity using plane and exponential coater geometries. The governing equations are derived from the laws of conservation of mass and momentum, and they are afterwards reduced using the lubrication approximation theory (LAT) to address the inherent process nonlinearities. We used the numerical shooting method in Mathematica to solve the differential equations. The Newtonian fluid results with constant viscosity are compared with those from the open literature and they are in the excellent agreement. Different governing parameters are analyzed in the reduced momentum equation. The influence of these dimensionless parameters on the velocity, pressure and pressure gradient are discussed and examined graphically whereas coating thickness and blade load are presented in tabulated form. It is observed that a Couple stress fluid with pressure-dependent viscosity improves load management and coating thickness, reducing costs and enhancing durability of the blade coating process.
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