自标定立体显微PIV系统研发及其在T型混合器中三维流动测量中的应用

A stereo-μ-PIV system for the measurement of all three components of the velocity vector in a measurement plane (2D-3C) in a closed microchannel has been developed and first test measurements have been performed on the three-dimensional laminar flow in a T-shaped micromixer. Stereo-μ-PIV measurements in closed microchannels require a calibration based on the self-calibration of the tracer particle images. In order to include the effects of different refractive indices of the water in the microchannel, the glass of the entrance window, and the surrounding air a three-media-model is included in the triangulation procedure of the self calibration. A preliminary test case shows that the stereo-μ-PIV results deviate less than 5% from theoretical values. First measurements in the mixing zone of a T-shaped micromixer show that three-dimensional flow in a microchannel can be resolved, however, the accuracy of the measurements needs to be improved.