Characteristic Investigation of Liquid–Liquid Droplet Flow in Microchannels by Using Micro-Scale Particle Image Velocimetry

• Main Authors: Bo-Rong Peng, 彭柏融
• Other Authors: Herchang Ay
• Format: Others
• Language: zh-TW
• Published: 2013
• Online Access: http://ndltd.ncl.edu.tw/handle/80199996541361886947

碩士 === 國立高雄應用科技大學 === 模具工程系碩士班 === 101 === As the microfluidic system technology develops vigorously, it is very important to study the characteristics of the about micro fluids. The applications of micro channel in generation mechanism and controlling technology are almost perfected, by Particle Image Velocimetry technology, investigate effect on two-phase flow of liquid-liquid droplet in micro-channels, the flow field within a micro-observation Complex fluid dynamics expansion. The droplet generating device used in this study is a T-junction microc-hannel the channel is built using a Micro electro mechanical systems（MEMS）. This study utilizes the optical visualization and Particle Image Velocimetry technology of inverted microscope to measure, changing the dimensionless Capillary number (Ca), continuous viscosity (μc), Film thickness (ε), Flow rate ratio of two phases (QR). The continuous phase fluid is silicon oil, the dispersed phase fluid is either DI water or diluted ethanol. Measure the generation mechanism, type of droplets in a water-in-silicon oil type, T-junction shaped micro-fluid generator, to investigate the three forms of droplets, plug flow, drops flow, and cobbles flow, within a the flow fields and characteristics. This study utilizes the analyze superimpose images, observed when the droplet is travelling within the channel, within a flow fields and characteristics. The dispersed phase fluid is either DI water, the droplets a internal flow field are boundary is the forwards vector； The dispersed phase fluid is diluted ethanol, the droplets a internal flow field are boundary is the backwards vector. Additional, Through changing the dispersed phase working fluids, increases as the Capillary number (Ca), will increase film thickness (ε), within the micro droplet in flow field vector Vortex Structure Length Ratio("" ). Interfacial tension (γ) is restraint by growing as the Film thickness (ε), and Vortex Structure Length Ratio("" ). Keywords: MEMS、micro-PIV、T-junction microc-hannel、Two phase flow、Droplet.