毛细管电渗流微泵的流型及驱动  

NUMERICAL SIMULATION OF ELECTROOMOTIC FLOW OF DRIVING PROCESS

作　　者：仲武[1] 陈云飞[1] 

机构地区：[1]东南大学MEMS教育部重点实验室,南京210096

出　　处：《机械工程学报》2006年第2期22-26,32,共6页Journal of Mechanical Engineering

基　　金：国家自然科学基金资助项目(50475077)

摘　　要：采用二维纳维一斯托克方程、拉普拉斯方程、泊松-玻尔兹曼方程表述电渗流微泵的计算模型,讨论了电渗流在各种工况下的流型,分析了双电层(EDL)厚度、外加垂直电势、Zeta电势、背压以及管径对电渗流(EOF)驱动时间的影响。仿真结果表明:影响驱动时间的主要是管径,其他因素可以忽略;无载驱动与反向驱动时间是毫秒级,有载驱动时间是在微秒级。通过改变外加垂直电势或Zeta电势的极性,可以实现双向驱动。Two dimensional Navier-Stokes equation, Laplace equation and Possiou Boltzmann equations are employed to set up mathematical model for electroosmotic driven flow. Various flow shapes under different load conditions are discussed. The effects of the eleetrical double layer （EDL） thickness, extra electrostatic field and zeta electrical potential on the start time of electroosmotic drive flow are exploited based on numerical simulation. It is demonstrated that the start time mainly depends on the tube diameter and the other factors such as the EDL thickness and Zeta potential contribute little to the start time. Numerical simulation also predicted that the start time for reverse driven and zero load driven flow is less than 1 milli-second and it is about microseconds under extem loads. Finally, it is proved that the electroosmotic driven flow can realize positive and reverse direction flow through changing the Zeta potential and external electric fields directions. This is interesting for electroosmotic pump potential applications on biochips and microfluid dynamics.

关 键 词：电渗流 无网格算法 MODIFIED Chorin-Teman(MCT)算法 驱动时间 

分 类 号：O351.2[理学—流体力学]