Plug-flow does not exist in electro-osmosis
نویسنده
چکیده
I eliminate hundred years old notion of ‘plug-flow’ in electro-osmosis, which was predicted by incomplete ‘electric double layer’ (EDL) theory. A recently developed ‘electric triple layer’ (ETL) theory removes some serious shortcomings of EDL theory regarding conservation of electric charge, and when applied to electro-osmosis, shows that the velocity profile is not ‘plug-like’ at all, but more like a parabola; it agrees with experiments and molecular dynamical simulation (MDS) results. Also, I redefine Helmholtz-Smoluchowski velocity-scale, which clears certain misunderstandings regarding representation of flow direction, and accommodates solution and geometrical properties within it. I describe some novel electro-osmotic flow controlling mechanisms. The entire electrokinetic theory must be modified using these concepts. PACS numbers: 47.61.-k, 82.45.-h, 47.65.-d, 85.85.+j Copyright c ©: Reserved by Rajib Chakraborty ∗ 89/3 Tanupukur Road, Dhakuria, Calcutta 700 031, West Bengal, India ; [email protected]
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