Electroosmotic flow through porous media: cylindrical and annular models

Electroosmotic flow rates through porous media are predicted through the cy lindrical and annular geometrical models. Differences in the results obtain ed from the two models are compared and discussed by making reference to th e electrokinetic remediation of contaminated soil. In the annular-model cas e, when the electrical potential on the outer wall is less than on the inne r wall and/or the double-layer thickness is much shorter than the outer rad ius, a maximum flux is predicted at some outer-to-inner-radii ratio. At a g iven soil porosity, the cylindrical model predicts a higher flow rate than the annular model, and the: difference becomes increasingly more pronounced as the radii ratio approaches unity, which corresponds to a low-porosity s oil. (C) 2000 Elsevier Science B.V. All rights reserved.