Flow rate control in micro channel with protrusions considering surface tension effect

Abstract

The roles of Micro fluidic devices have become more important in micro-system industries because of mass production of micro-components for most application. Especially micro protein chip, used to diagnosis human disease, must be able to control the flow rate for successful medical examination. In this study, micro channel with various geometry of protrusions are considered. Numerical analyses have been performed to figure out the geometric effects on the flow rate. A numerical analysis has also been developed taking account of the surface tension effect which is the effective driving force in micro scales. Piecewise Linear Interface Construction-Volume of Fluid (PLIC-VOF) method has been used for the numerical simulation of gas-liquid flows with an explicit tracking of the phase interface. For the treatment of surface tension effects, a Continuum Surface Force (CSF) model is also coupled. The simulations show that the surface chemistry (hydrophilic / hydrophobic) is appeared to be a dominating factor of the flow process. According to this study, the numerically analyzed results can obviously reveal the intimate relations between protrusions and flow rate with various conditions