微流控芯片中电渗流的数值模拟与仿真研究

Numerical simulation research on electroosmotic flow in microfluidic chip

从电渗流形成的基本理论入手,推导了电场和流场双物理场耦合的控制方程。运用多物理场数值计算分析软件建立了长为1000μm,宽为100μm的二维流道,在微流道中间250~750μm的区域施加了直流电压,并在数值模拟中还原了微流道内壁和微流体的物理属性,计算得出了各段流体的速度场,进而得出了各段流体的流型。通过二维流道压力分布分析了微流道中各段产生不同流型的原因。对微流控芯片中的电动流动的功能原理分析及优化设计具有借鉴意义。

Start with basic theoretical research of electroosmotic flow,with the combination of electrical field and hydrodynamics field,a numerical simulation method of the electroosmotic flow and pressure driven flow inside a 2D model of the microchannel is carefully studied. In our model for simulation,the microchannel is 1000 μm in length and 100 μm in width,a DC power is supplied between the areas from 250 μm to 750 μm to initiate the electroosmotic flow,the physical and chemical properties of the fluid inside the channel and the channel walls are also carefully chosen during the numerical simulation. The flow pattern and velocity field the fluids inside the microchannel is obtained during the numerical simulation. With the careful study of the pressure distribution inside the microchannel,the different flow patterns at the different areas inmicrochannel were explained. This study reveals some new interesting findings for the electroosmotic flow inside the microfluidic devices,and has some potential impact for the design and optimization of the electroosmotic driven microfluidic devices.