Laboratory for Flow Control-Fluid mechanics experiment for science & technology-

Color PIV

Particle Image Velocimetry (PIV) has advanced to three-dimensional three-component velocity vector field measurements in the last two decades. Among several types of 3D PIVs, use of color volumetric illumination allows a single-camera 3D measurement. Our laboratory developed two different kinds of Color PIV. One is Color PIV applicable to wind tunnel experiments, i.e. aerodynamic studies. This method relies on color decontamination [1] for smoke images that have particle-per-pixel value higher than unity. We applied this technique to engineering researches including 3D wake flow diagnosis for a delta wing and turbulent boundary layer subject to high heat transfer. The other technique is Color PTV (Particle Tracking Velocimetry) good for liquid flow measurements. Use of structured volumetric illumination [2] [3] and animation control [4] for the color-coding greatly improved the measurement performance. The technique was applied for rotating turbines, thermal convection, container’s mixing, and flow structures around moving objects. Some of them includes machine-learning for colored opto-geometric calibration [5] to highly improve the measurement accuracy.

1. Murai, Yumoto et al. Experiments in Fluids, 62, 231 (2021)
2. Park, Yamagishi et al. Experiments in Fluids, 62, 70 (2021)
3. Park, Saito et al. Experimental Thermal and Fluid Science, 109, 109919 (2019)
4. Watamura, Tasaka, Murai. Experimental Thermal and Fluid Science, 47, 68–80 (2013)
5. Noto, Tasaka, Murai. Experiments in Fluids, 62, 131 (2021)