Abstract:A MicroPIV system for nonNewtonian fluid field measurement was introduced. The system mainly included three parts: micro flow field excitation, micro flow observation and data processing part. For the diversity of the micro flow excitation for the nonNewtonian fluid, there were many differences for the micro flow field excitation part from the normal MicroPIV system. A microscope hot and cool stage, a waveform generator and a magnetic field generator were included in this part, and with these selfmade instruments, the nonNewtonian micro flow were excited. The observation and record part mainly included the fluorescence microscope, the CCD and so on, which is used to observe and record the movement of the fluorescent tracer particles. The data processing part was used for image processing to the video file of the tracer particles from the observation part. This system was used to measure the micro flow field under the action of the electric field and the temperature field for the test. In the experiment, the non Newtonian fluid liquid crystalline 5CB was used. Under the electric field, the micro flow was induced. The experiment was focusing on the measurement of the velocity profile of the side liquid crystalline cell. The obtained results agree to the simulation results very well qualitatively, and with this system, the results can be achieved faster and more accurate than the traditional experiment method. In addition, the liquid crystalline defects caused by the temperature field were studied with this system, and the temperature changing trend at which the liquid crystalline defect was formed was achieved. Under the condition of continuous heating and cooling processing, the defect forming temperature increases from 3125 ℃ to 344 ℃.
