Rheological Study of Non-isothermal Viscoelastic Fluid in Reverse Roll Coating Phenomena

The purpose of this article is to present a mathematical and theoretical model of reverse roll coating for a thin film using an incompressible, non-isothermal upper-convected Jeffery's Fluid. This model is used to represent viscoelastic fluids, which have viscous and elastic properties. The behavior of these complex fluids under shear and extensional flows can be predicted with the use of this model. The fluid moves between two rollers that are rotating counterclockwise in a narrow space. Using dimensionless parameters, dimensionless governing equations are produced. These dimensionless equations are reduced by the lubrication approximation theory (LAT). Analytical findings for velocity profile, pressure gradient, and temperature distribution are obtained by employing the perturbative technique. The pressure distribution, web-coated thickness, separation points, roll separating force, and power input were all numerically calculated from an engineering perspective. The separation point is shifted toward the nip zone, and the web coating thickness is decreased by increasing the velocity ratio k. The temperature profile is significantly influenced by the Brinkman number, which has increased as a result. The findings show that the viscoelastic parameter and velocity ratio have a significant impact on the velocity profile and pressure.