Volume reconstruction around bodies for 3D PIV

During 3D PIV experiments, bodies can create fully or partially occluded regions in the measurement volume. By simulating multi-camera PIV experiments with occlusions present, we show that the quality of 3D tracer particle reconstruction depends on the camera configuration and experiment attributes such as the seeding density, particle image radius, thickness of the measurement volume, and the size and brightness of the occlusion. We compare particle reconstruction algorithms to determine which performs best when occlusions are present. We further break down the reconstruction quality by the number of viewing versus occluded cameras and characterize relationships between particle reconstruction quality and velocity field accuracy in partially-occluded regions. Based on these findings, we apply the highest performing imaging and reconstruction parameters from our simulations to an experiment, where they can be combined with experimental improvements, such as fluorescent particles to minimize reflections, to further improve near-body measurements.