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Design of a set-up for high-accuracy 3D PTV measurements in turbulent pipe flow

Turbulent flows are often encountered in common practice, usually at high Reynolds number. The development of Lagrangian stochastic models of these flows requires knowledge of Lagrangian statistics. To study the Lagrangian statistics of turbulent pipe flow, a dedicated 3D particle tracking velocimetry set-up has been designed. In this paper, design parameters, selection criteria and solutions are discussed. The measurement accuracies are studied in detail. Typical 3D particle tracking velocimetry results for turbulent pipe flow are compared and found to be in good agreement with direct numerical simulations.