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Title: Miniature rainbow schlieren deflectometry system for quantitative measurements in microjets and flames

Abstract

Recent interest in small-scale flow devices has created the need for miniature instruments capable of measuring scalar flow properties with high spatial resolution. We present a miniature rainbow schlieren deflectometry system to nonintrusively obtain quantitative species concentration and temperature data across the whole field. The optical layout of the miniature system is similar to that of a macroscale system, although the field of view is smaller by an order of magnitude. Employing achromatic lenses and a CCD array together with a camera lens and extension tubes, we achieved spatial resolution down to 4 {mu}m. Quantitative measurements required a careful evaluation of the optical components. The capability of the system is demonstrated by obtaining concentration measurements in a helium microjet (diameter, d=650 {mu}m) and temperature and concentration measurements in a hydrogen jet diffusion flame from a microinjector(d=50 {mu}m). Further, the flow field of underexpanded nitrogen jets is visualized to reveal details of the shock structures existing downstream of the jet exit.

Authors:
; ; ;
Publication Date:
OSTI Identifier:
20929734
Resource Type:
Journal Article
Resource Relation:
Journal Name: Applied Optics; Journal Volume: 46; Journal Issue: 15; Other Information: DOI: 10.1364/AO.46.002954; (c) 2007 Optical Society of America; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; 37 INORGANIC, ORGANIC, PHYSICAL AND ANALYTICAL CHEMISTRY; CAMERAS; CHARGE-COUPLED DEVICES; COMBUSTION; EQUIPMENT; EVALUATION; FLAMES; HELIUM; HYDROGEN; LENSES; MEASURING METHODS; NITROGEN; SPATIAL RESOLUTION; TEMPERATURE MEASUREMENT

Citation Formats

Satti, Rajani P., Kolhe, Pankaj S., Olcmen, Semih, and Agrawal, Ajay K. Miniature rainbow schlieren deflectometry system for quantitative measurements in microjets and flames. United States: N. p., 2007. Web. doi:10.1364/AO.46.002954.
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Satti, Rajani P., Kolhe, Pankaj S., Olcmen, Semih, & Agrawal, Ajay K. Miniature rainbow schlieren deflectometry system for quantitative measurements in microjets and flames. United States. doi:10.1364/AO.46.002954.
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Satti, Rajani P., Kolhe, Pankaj S., Olcmen, Semih, and Agrawal, Ajay K. Sun . "Miniature rainbow schlieren deflectometry system for quantitative measurements in microjets and flames". United States. doi:10.1364/AO.46.002954.
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@article{osti_20929734,
title = {Miniature rainbow schlieren deflectometry system for quantitative measurements in microjets and flames},
author = {Satti, Rajani P. and Kolhe, Pankaj S. and Olcmen, Semih and Agrawal, Ajay K},
abstractNote = {Recent interest in small-scale flow devices has created the need for miniature instruments capable of measuring scalar flow properties with high spatial resolution. We present a miniature rainbow schlieren deflectometry system to nonintrusively obtain quantitative species concentration and temperature data across the whole field. The optical layout of the miniature system is similar to that of a macroscale system, although the field of view is smaller by an order of magnitude. Employing achromatic lenses and a CCD array together with a camera lens and extension tubes, we achieved spatial resolution down to 4 {mu}m. Quantitative measurements required a careful evaluation of the optical components. The capability of the system is demonstrated by obtaining concentration measurements in a helium microjet (diameter, d=650 {mu}m) and temperature and concentration measurements in a hydrogen jet diffusion flame from a microinjector(d=50 {mu}m). Further, the flow field of underexpanded nitrogen jets is visualized to reveal details of the shock structures existing downstream of the jet exit.},
doi = {10.1364/AO.46.002954},
journal = {Applied Optics},
number = 15,
volume = 46,
place = {United States},
year = {Sun May 20 00:00:00 EDT 2007},
month = {Sun May 20 00:00:00 EDT 2007}
}
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Journal Article:
DOI:  10.1364/AO.46.002954
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  • ; ; - Applied Optics

  • ; ; - Applied Optics
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  • ; ; ; ... - Review of Scientific Instruments
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