Electroosmotic flow of a general electrolyte solution through a fibrous medium

JOURNAL OF COLLOID AND INTERFACE SCIENCE

卷:223

Article

Lee, E ; Lee, YS ; Yen, FY ; Hsu, JP

关键词: electroosmotic flow;    electrolyte solution;    fibrous medium;    electrokinetic equations;    double-layer polarization;   

DOI  :  10.1006/jcis.1999.6626

来源: Elsevier

【 摘 要 】

The electroosmotic flow of a general electrolyte solution through a fibrous medium is modeled theoretically taking the effect of double-layer polarization into account. The result obtained is applicable to an arbitrary level of electrical potential. We show that if the effect of double-layer polarization is neglected using the linearized Poisson-Boltzmann equation will underestimate electroosmotic velocity. The deviation becomes inappreciable, however, if kappa a is either very large or very small, kappa and a being, respectively, the reciprocal Debye length and the radius of a fiber. If the surface potential is high, the variation of electroosmotic velocity as a function of kappa a may exhibit a local maximum and a local minimum, and the larger the porosity of the fibrous medium the lower the level of surface potential for the local extremals to occur. If kappa a is small, the effect of surface potential on the electroosmotic velocity is more significant than that of double-layer polarization, and the reverse is true if kappa a is large, (C) 2000 Academic Press.

【 授权许可】

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