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arXiv · 1603.03816

Fluid flow vorticity measurement using laser beams with orbital angular momentum

A. Ryabtsev·S. Pouya·A. Safaripour·M. Koochesfahani·M. Dantus
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Abstract

We report on the direct measurements of fluid flow vorticity using a spatially shaped beam with a superposition of Laguerre-Gaussian modes that reports on the rotational Doppler shift from microparticles intersecting the beam focus. Experiments are carried out on fluid flows with well-characterized vorticity and the experimental results are found to be in excellent agreement with the expected values even for 200 ms integration times. This method allows for localized real-time determination of vorticity in a fluid flow.

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A. Ryabtsev, S. Pouya, A. Safaripour, M. Koochesfahani, M. Dantus. 2016-03-11. Fluid flow vorticity measurement using laser beams with orbital angular momentum. https://doi.org/10.1364/oe.24.011762

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