| Article ID | Journal | Published Year | Pages | File Type |
|---|---|---|---|---|
| 740502 | Sensors and Actuators A: Physical | 2007 | 6 Pages |
Droplets-based method has been employed to enhance mixing in microfluidic systems. This paper presents experimental studies of the recirculating flow field inside a moving droplet and the characterization of the mixing of two aqueous droplets. In the first part, the velocity field inside the moving water droplet was measured using the micro-particle image velocimetry (micro-PIV) technique. The PIV measurements showed that recirculation flow exists inside the droplet. However, the findings suggested that the outer layer of droplets move at a faster velocity than the central part. The result is different from what is reported by other researchers. In the second part, two water droplets, a de-ionized (DI) water droplet and another DI water droplet with fluorescent dye, were brought together by the carrier fluid to form a bigger droplet. The mixing between the two aqueous droplets was characterized by the fluorescent dye concentration distribution.
