The in uence of viscoelastic rheology on blade coating as revealed bynumerical methods 1

The innuence of an elastic component of the rheological properties of the coating suspension on the coating ow in the blade coating process was investigated by numerical methods. The Giesekus model was used as the constitutive equation for the coating uid (coating colour). The system of time-dependent partial diierential equations was solved numerically by dis-cretising the solution with nite diierences on an overlapping composite grid. The numerical results reveal that the elastic behaviour of the coating colours, characterized with a relaxation parameter, can have a decisive eeect on the behaviour of the coating colour in the vicinity of the blade tip. The calculated colour-related forces acting on the surface of the substrate and on the blade tip were lower with a viscoelastic colour than those emanating from a corresponding simulation using a Newtonian colour.