Modelling of fluid/paper interaction in the application nip of a film coater

This paper describes a model for the penetration of fluid into a moving pap er web in the application nip of a film coater. One-dimensional and two-dim ensional solution methods are developed and compared. The two-dimensional m odel is solved using a Galerkin finite element method with a free surface a lgorithm. The depth of fluid penetration into the paper web increases with increase in applied pressure, paper permeability and exposure time. The flu id penetration depth decreases as the porosity or solution viscosity increa ses. The functional relationship among these variables depends on the profi le of the pressure applied at the surface of the paper sheet. For the case of uniform paper permeability and no air compression in the web, the two-di mensional model gives similar results to the one-dimensional model.