We describe a Lagrangian particle tracking technique that can be applied to high Reynolds number turbulent flows. This technique produces three-dimensional Lagrangian trajectories of multiple particles, from which both Lagrangian and Eulerian statistics can be obtained. We illustrate the application of this technique with measurements performed in a von Karman swirling flow generated in a vertical cylindrical tank between two counter-rotating baffled disks. The Taylor microscale Reynolds number investigated runs from 200 to 815. The Kolmogorov time scale of the flow was resolved and both the turbulent velocity and acceleration were obtained and their probability density functions measured. Measurements of the Eulerian and Lagrangian velocity structure functions are presented. The average energy dissipation rates are determined from the Eulerian velocity structure functions.
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