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DOE OSTI · 1634808

Multi-line FLEET by imaging periodic masks

Zhang, Yibin·Marshall, Garrett·Beresh, Steven J.·Richardson, Daniel·Casper, Katya M.
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Abstract

A simple linear configuration for multi-line FLEET velocimetry is used for the first time to image an overexpanded unsteady supersonic jet. The FLEET lines are spaced 0.5-1.0 mm apart and up to six lines can simultaneously be used to visualize the flowfield. These lines are created using periodic masks, despite the mask blocking 25 — 30% of the 10 mJ incident beam. Maps of mean single-component velocity in the direction along the principal flow axis, and turbulence intensity in that same direction, are created using multi-line FLEET, and computed velocities agree well with that obtained from single-line (traditional) FLEET. Compared to traditional FLEET, multi-line FLEET offers increased simultaneous spatial coverage and the ability to produce spatial correlations in the streamwise direction. This FLEET permutation is especially well-suited for short-duration test facilities

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Zhang, Yibin, Marshall, Garrett, Beresh, Steven J., Richardson, Daniel, Casper, Katya M.. 2020-07-10. Multi-line FLEET by imaging periodic masks. https://doi.org/10.1364/ol.392779

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