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arXiv · 2304.02967

Imaging Temperature and Thickness of Thin Planar Liquid Water Jets in Vacuum

Abstract

We present spatially resolved measurements of the temperature of a flat liquid water microjet for varying pressures, from vacuum to 100% relative humidity. The entire jet surface is probed in a single shot by a high-resolution infrared camera. Obtained 2D images are substantially influenced by the temperature of the apparatus on the opposite side of the IR camera; a protocol to correct for the thermal background radiation is presented. In vacuum, we observe cooling rates due to water evaporation on the order of 105 K/s. For our system, this corresponds to a temperature decrease of approximately 15 K between upstream and downstream positions of the flowing leaf. Making reasonable assumptions on the absorption of the thermal background radiation in the flatjet we can extend our analysis to infer a thickness map. For a reference system our value for the thickness is in good agreement with the one reported from white light interferometry.

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Tillmann Buttersack, Henrik Haak, Hendrik Bluhm, Uwe Hergenhahn, Gerard Meijer, Bernd Winter. 2023-04-06. Imaging Temperature and Thickness of Thin Planar Liquid Water Jets in Vacuum. https://doi.org/10.1063/4.0000188

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