Depleted layer effects in polymer flow through porous media. I. Single capillary calculations

Polymer molecules may be entropically excluded from a region of fluid close to the wall in a narrow capillary or flow channel in a porous medium. This effect results in a layer of polymer-depleted solution close to the wall which causes both apparent viscous slip effects and velocity enhancement of the polymer molecules relative to the solvent molecules. In this paper, theoretical calculations are presented on the effects of the depleted layer on the rheological and transport properties of the polymer solution in capillaries. This work extends earlier simple models to include more complex analytical forms of the layer profile and flow rate effects. © 1990.