Experimental measurement of electrical conductivity and electro-osmotic permeability of ionised porous media

Fine grained porous media typically exhibit non-Darcian behaviour. One of them is electro-osmotic flow. The present paper presents an electro-osmotic flow experiment on hydrogel samples. The electric current density is prescribed. The electric potential drop across the sample and the volume flow through the sample are measured. The results show a linear relationship between potential and current and between flow and current. As diffusional properties are highly dependent on deformation, these linear relationships in a highly deformable medium, support the theoretical finding that viscous drag is annihilated by opposite electrical forces in an electroosmotic flow experiment