Abstract: A new particle image velocimetry technology for microfluidic device made by micro system technology is presented. The Micro-PIV system is setup by adding an epi-fluorescence microscope and improving the light source and choosing the special type of tracing particle. According to micron dimension flow scale and high precision request, an image processing based on cross correlation algorithm is discussed. Aim at eliminating the main error caused by Brown motion of tracing particle, a method by averaging velocities of ensemble particles in the same interrogation plot is also advanced. Three classic flow fields are detected by Micro-PIV system. The results show that this device is fit for steady and transient flow with micron dimension scales.

Key words: Brown motion, Micro fluidic system, Micro-PIV, Tracing particle