Traditional Stereo Particle Image Velocimetry (SPIV) is able to visualize a single slice of wake structure, but I am struggling to understand the 3D wake structure based on limit 2D visualization. Thus, I developed a semi-automated 3D PIV system that able to visualize the large volume complex 3D wake structure around the bio-inspired robot fish.
To visualize the flow around the platform, I measured 14 SPIV layers by keeping the laser sheet stationary and raising/lowering the leveling system stepper motors synchronously. Then, I mirrored these layers across a horizontal plane at the midline to estimate the flow around the upper half of the platform.
The final output was phase-averaged across 25 pitching cycles, all post-processing was performed in Matlab and visualized in Tecplot.