Electrokinetic Vortices and Traveling Waves in Nondilute Colloidal Dispersions

详细信息    查看全文

• 作者：Carlos L. Prez ; Jonathan D. Posner
• 刊名：Langmuir
• 出版年：2010
• 出版时间：June 15, 2010
• 年：2010
• 卷：26
• 期：12
• 页码：9261-9268
• 全文大小：1067K
• 年卷期：v.26,no.12(June 15, 2010)
• ISSN：1520-5827

文摘

We report a diverse set of coherent fluid flow instabilities, particle patterns, and traveling waves that develop when an ac electric field is applied to nondilute colloidal dispersions with volume fractions that span 3 orders of magnitude. Novel observed phenomena include the following: vortices with steady and unsteady axes of rotation, unsteady time evolution of vortices formation and vortex merging, as well as traveling waves that propagate through the dispersion. Vortical flows are influenced by strong interactions between particle electrical dipoles as well as electric body forces due to electric fields coupled with gradients in particle volume fraction. We use a 1D Burgers equation to predict the existence of traveling waves in colloidal dispersions.