Rheological tests with a Boger fluid and a rough geometry

In rheometry rough geometries are often used to prevent wall-slip typically encountered with heterogeneous fluids. However, the fluid does not stand still within the geometry roughness and a residual wall-slip can be often measured. The problem can be treated as the flow through a porous medium that is here investigated when the fluid is non-Newtonian. We use a Boger fluid that is a good model for the Second Order Fluids and a commercial cross-hatched plate as rough geometry. The results obtained are in good qualitative agreement with predictions available in the literature and are promising for the development of a simple procedure to use rough geometries with viscoelastic fluids