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Global Doppler frequency shift detection with near-resonant interferometry

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Abstract

The recent development in measuring 2D Doppler shift distributions for flow velocimetry using the dispersive properties of atomic line filters is presented. On the basis of velocity field measurements on a subsonic jet flow and a tip vortex flow in a medium-sized wind tunnel, the technique was assessed. Atomic line filters near a resonant transition combine imaging capabilities with a sharp frequency cutoff and an associated region of strong anomalous dispersion. While conventional Doppler global velocimetry relies on the absorption of the filter to convert frequency shifts to intensity variations, near-resonant interferometry uses its dispersion to detect frequency shifts as phase changes in an interference pattern. In the present setup, an iodine vapor cell in an imaging Michelson interferometer is used. With the illuminating laser frequency tuned near a resonant transition, the cell’s dispersion converts the frequency content of the field of view into a distortion of the carrier-fringe pattern recorded at the image plane of the interferometer. The phase distribution in the fringe images is reconstructed by filtering the individual images with a 2D Gabor filter pair tuned to the spatial frequencies of the basic carrier-fringe pattern. The post-processing is concluded with subsequent phase-unwrapping and subtraction of the carrier reference fringe phase. The method and the setup were demonstrated and calibrated experimentally on a rotating disc. The capability of the technique to operate in a real experimental environment was validated in a free subsonic jet and a tip vortex flow behind a wing section in a medium-sized wind tunnel facility. The measurements were found to be in generally good agreement with the theoretically predicted system characteristics and the reference measurements. As with other Doppler global techniques, the stability of the pulsed laser system and the secondary scattering in the test volume were identified as the main error sources.

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Abbreviations

ALF:

Atomic line filter

AOA:

Angle of attack

DGV:

Doppler global velocimetry

DPV:

Doppler picture velocimetry

FWHM:

Full width at half maximum

ICCD:

Intensified charge-coupled device

LDV:

Laser Doppler velocimetry

PDV:

Planar Doppler velocimetry

PIV:

Particle image velocimetry

RMS:

Root mean square

References

  • Fischer A, Büttner L, Czarske J, Eggert M, Grosche G, Müller H (2007) Investigation of time-resolved single-detector Doppler global velocimetry using sinusoidal laser frequency modulation. Meas Sci Technol 18:2529–2545

    Article  Google Scholar 

  • Ford HD, Nobes DS, Tatam RP (2001) Acousto-optic frequency switching for single-camera planar Doppler velocimetry. Proc Soc Photo Opt Instrum Eng 4448:272–282

    Google Scholar 

  • Forkey JN, Lempert WR, Miles RB (1997) Corrected and calibrated I2 absorption model at frequency-doubled Nd:YAG laser wavelengths. Appl Opt 36(27):6729–6738

    Article  Google Scholar 

  • Gerstenkorn S, Luc P (1978) Atlas du spectre d’Absorption de la Molecule d’Iode, 14,800–20,000 cm−1. Laboratoire Aimé-Cotton CNRS II, Orsay

    Google Scholar 

  • Ghiglia DC, Romero LA (1994) Robust two-dimensional weighted and unweighted phase unwrapping that uses fast transforms and iterative methods. J Opt Soc Am A 11(1):107–117

    Article  Google Scholar 

  • Jähne B (2005) Digital image processing. 6 th rev. and extended edn. Springer, Heidelberg

    Google Scholar 

  • Komine H, Brosnan SJ, Litton AB, Stappaerts EA (1991) Real-time Doppler global velocimetry. In: AIAA 29th Aerospace Sciences Meeting, Reno, Nevada, paper 91-0337

  • Landolt A, Roesgen T (2006) Global Doppler frequency shift detection with near-resonant interferometry. In: 13 th Int Symp. on applications of laser techniques to fluid mechanics, Lisbon, Portugal, p 21.7

  • Lu Z-H, Charrett TOH, Ford HD, Tatam RP (2007) Mach–Zehnder interferometric filter based planar Doppler velocimetry (MZI-PDV). J Opt A Pure Appl Opt 9(11):1002–1013

    Article  Google Scholar 

  • Meier AH, Roesgen T (2009) Heterodyne Doppler global velocimetry. In: 14th international symposium on applications of laser techniques to fluid mechanics, Lisbon, Portugal, p 7.3.4. Exp Fluids. doi:10.1007/s00348-009-0647-0

  • Meyers JF (1995) Development of Doppler global velocimetry as a flow diagnostics tool. Meas Sci Technol 6:769–783

    Article  Google Scholar 

  • Meyers JF, Lee JW, Schwartz RJ (2001) Characterization of measurement error sources in Doppler global velocimetry. Meas Sci Technol 12:357–368

    Article  Google Scholar 

  • Miles RB, Yalin AP, Tang Z, Zaidi SH, Forkey JN (2001) Flow field imaging through sharp-edged atomic and molecular ‘notch’ filters. Meas Sci Technol 12:442–451

    Article  Google Scholar 

  • Peiponen KE, Vartiainen EM, Asakura (1998) Dispersion, complex analysis and optical spectroscopy. Springer,

    Google Scholar 

  • Seiler F, Oertel H (1983) Visualization of velocity fields with Doppler-pictures. In: 3rd Int. Symp. on flow visualization, Ann Arbor

  • Seiler F, George A, Srulijes J, Havermann M (2008) Flow Progress in Doppler picture velocimetry (DPV). Exp Fluids 44:389–395

    Article  Google Scholar 

  • Tellinghuisen J (1982) Transition strengths in the visible-infrared absorption spectrum of I2. J Chem Phys 76(10):4736–4744

    Article  Google Scholar 

  • Willert C, Stockhausen G, Klinner J, Lempereur C, Barricau P, Loiret P, Raynal JC (2007) Performance and accuracy investigations of two Doppler global velocimetry systems in parallel. Meas Sci Technol 18:2504–2512

    Article  Google Scholar 

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Authors and Affiliations

  1. Institute of Fluid Dynamics, ETH, Zurich, Switzerland

    Andrin Landolt & Thomas Roesgen

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  1. Andrin Landolt
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  2. Thomas Roesgen
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Correspondence to Andrin Landolt.

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Landolt, A., Roesgen, T. Global Doppler frequency shift detection with near-resonant interferometry. Exp Fluids 47, 733–743 (2009). https://doi.org/10.1007/s00348-009-0688-4

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  • DOI: https://doi.org/10.1007/s00348-009-0688-4

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