Roll-over-web coating analysis of micropolar-Casson fluid: a theoretical investigation

The theoretical model of micropolar-Casson fluid is studied in roll-coating over a moving substrate based on the lubrication theory. Closed-form solutions for the velocity, pressure gradient, and microrotation are attained, while a numerical technique employed to compute interesting engineering variables such as pressure, roll-separating force, separating point, and power input. The influence of involved parameters on the physical and engineering quantities are displayed via graphs and table. The coupling number (N) and viscoplastic parameter (beta) provide the controlling mechanism for the exit sheet thickness, separating force, and power input. Also, the pressure gradient and pressure profile in the nip region enhances for large values of coupling number (N) whereas the viscoplastic parameter (beta) gives the opposite behavior.