Validation of PSV for turbulence measurements and modeling

The non-linear Navier-Stokes equations, which govern fluid flow, are one of the last unsolved problems in the fluid mechanics community. Since there is no analytical solution for turbulence, researchers rely on numerical modeling and empirical relations derived from experiments. Over the years, several techniques have been developed to measure turbulent flow fields including pitot-tubes, pressure transducers and hot-wires. These techniques are intrusive to the flow field and thus laser-based diagnostics were developed to alleviate this concern. These optical techniques include laser-doppler anemometry (LDA) and particle image velocimetry (PIV). This paper explores a relatively new technique, known as particle shadow velocimetry (PSV), to make turbulence measurements. Specifically, turbulence characteristics that can be quantified from multi-plane PSV. The radial profile of a fully developed pipe flow is measured using standard planar PSV and again with multiplane PSV for comparison. It was found that the statistical quantities of the multiplane PSV data are within the experimental uncertainty of the single plane PSV and previously published LDV data.