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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 ambient 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 infrared 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 in 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.

SUBMITTER: Buttersack T

PROVIDER: S-EPMC10314331 | biostudies-literature | 2023 May

REPOSITORIES: biostudies-literature

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Imaging temperature and thickness of thin planar liquid water jets in vacuum.

Buttersack Tillmann T Haak Henrik H Bluhm Hendrik H Hergenhahn Uwe U Meijer Gerard G Winter Bernd B

Structural dynamics (Melville, N.Y.) 20230501 3

We present spatially resolved measurements of the temperature of a flat liquid water microjet for varying ambient 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 infrared camera; a protocol to correct for the thermal background radiation is presented. In vacuum, we observe cooling rates due to wat ...[more]

PMID: 37398627

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Imaging temperature and thickness of thin planar liquid water jets in vacuum.

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Imaging temperature and thickness of thin planar liquid water jets in vacuum.

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