3D hypergraph-oriented air flow analysis based on PTV

The paper introduces a new air flow analysis approach based on Particle Tracking Velocimetry (PTV). One of the special features of the proposed method is that after the tracer particles are detected, matching and tracing are conducted jointly. To this end, we introduce an interpretation module based on a directed hypergraph for 3D curve reconstruction. At first the 2D inter-frame locations are localised and used for the extraction and calculation of 3D keypoints. Through 3D keypoints which are evaluated in several steps by the hypergraph together with the time information, reverse curve matching for path selection can be reconstructed and the resulting trajectories visualized. In contrast to the preceding work, our approach describes the measuring data by 3D trajectories directly instead of first estimating 2D trajectories and then matching them to 3D trajectories. Even with complicated trajectories, a higher precision can be achieved. A certain independence of the reflections and lighting conditions is reached by interpretation. Moreover, the path of particles can also be reconstructed with the minimum number of 3D keypoints under consideration of path energy minimization.