OSA's Digital Library

Applied Optics

Applied Optics


  • Editor: Joseph N. Mait
  • Vol. 52, Iss. 22 — Aug. 1, 2013
  • pp: 5562–5569

Measurement of temperature and velocity fields in a convective fluid flow in air using schlieren images

A. Martínez-González, D. Moreno-Hernández, and J. A. Guerrero-Viramontes  »View Author Affiliations

Applied Optics, Vol. 52, Issue 22, pp. 5562-5569 (2013)

View Full Text Article

Enhanced HTML    Acrobat PDF (961 KB)

Browse Journals / Lookup Meetings

Browse by Journal and Year


Lookup Conference Papers

Close Browse Journals / Lookup Meetings

Article Tools



A convective fluid flow in air could be regulated if the physical process were better understood. Temperature and velocity measurements are required in order to obtain a proper characterization of a convective fluid flow. In this study, we show that a classical schlieren system can be used for simultaneous measurements of temperature and velocity in a convective fluid flow in air. The schlieren technique allows measurement of the average fluid temperature and velocity integrated in the direction of the test beam. Therefore, in our experiments we considered surfaces with isothermal conditions. Temperature measurements are made by relating the intensity level of each pixel in a schlieren image to the corresponding knife-edge position measured at the exit focal plane of the schlieren system. The same schlieren images were also used to measure the velocity of the fluid flow by using optical flow techniques. The algorithm implemented analyzes motion between consecutive schlieren frames to obtain a tracked sequence and finally velocity fields. The proposed technique was applied to measure the temperature and velocity fields in natural convection of air due to unconfined and confined heated rectangular plates.

© 2013 Optical Society of America

OCIS Codes
(100.0100) Image processing : Image processing
(100.2000) Image processing : Digital image processing
(100.2960) Image processing : Image analysis
(110.2960) Imaging systems : Image analysis
(120.4640) Instrumentation, measurement, and metrology : Optical instruments
(120.6780) Instrumentation, measurement, and metrology : Temperature

ToC Category:
Instrumentation, Measurement, and Metrology

Original Manuscript: March 12, 2013
Revised Manuscript: May 8, 2013
Manuscript Accepted: June 6, 2013
Published: August 1, 2013

A. Martínez-González, D. Moreno-Hernández, and J. A. Guerrero-Viramontes, "Measurement of temperature and velocity fields in a convective fluid flow in air using schlieren images," Appl. Opt. 52, 5562-5569 (2013)

Sort:  Author  |  Year  |  Journal  |  Reset  


  1. Graham O. Hughes and Ross W. Griffiths, “Horizontal convection,” Annu. Rev. Fluid Mech. 40, 185–208 (2008). [CrossRef]
  2. J. A. Schetz and A. E. Fuhs, Handbook of Fluid Dynamics and Fluid Machinery: Experimental and Computational Fluid Dynamics (Wiley, 2009), Vol. 2.
  3. A. K. Agrawal, N. K. Butuk, S. R. Gollahalli, and D. Griffin, “Three-dimensional rainbow schlieren tomography of a temperature field in gas flows,” Appl. Opt. 37, 479–485 (1998). [CrossRef]
  4. V. P. Tregub, “A color schlieren method,” J. Opt. Technol. 71, 785–790 (2004). [CrossRef]
  5. T. Wong and A. K. Agrawal, “Quantitative measurements in an unsteady flame using high-speed rainbow schlieren deflectometry,” Meas. Sci. Technol. 17, 1503–1510 (2006). [CrossRef]
  6. E. M. Popova, “Processing schlieren-background patterns by constructing the direction field,” J. Opt. Technol. 71, 572–574 (2004). [CrossRef]
  7. M. Raffe, H. Richard, and A. G. E. A. Meier, “On the applicability of background oriented optical tomography for large scale aerodynamic investigations,” Exp. Fluids 28, 477–481 (2000). [CrossRef]
  8. R. B. Teese and M. M. Waters, “Inexpensive schlieren video technique using sensor dead space as a grid,” Opt. Eng. 43, 2501–2502 (2004). [CrossRef]
  9. S. Garg and L. N. Cattafesta, “Quantitative schlieren measurements of coherent structures in a cavity shear layer,” Exp. Fluids 30, 123–134 (2001). [CrossRef]
  10. C. Alvarez-Herrera, D. Moreno-Hernández, B. Barrientos-García, and J. A. Guerrero-Viramontes, “Temperature measurement of air convection using a schlieren system,” Opt. Laser Technol. 41, 233–240 (2009). [CrossRef]
  11. W. Merzkirch, Flow Visualization, 2nd ed. (Academic, 1987).
  12. G. S. Settles, Schlieren and Shadowgraph Technique (Springer, 2001).
  13. H. C. H. A. Townsend, “A method of airflow cinematography capable of quantitative analysis,” J. Aeronaut. Sci. 3, 343–352 (1936).
  14. D. I. Papamoschou, “A two-spark schlieren system for very-high velocity measurement,” Exp. Fluids 7, 354–356 (1989). [CrossRef]
  15. S. Fu and Y. Wu, “Detection of velocity distribution of a flow field using sequences of schlieren images,” Opt. Eng. 40, 1661–1666 (2001). [CrossRef]
  16. M. A. Kegerise and G. S. Settles, “Schlieren image-correlation velocimetry and its application to free-convection flows,” in Proceedings of the Ninth International Symposium on Flow Visualization, G. M. Carlomagno and I. Grant, eds. (2000), paper 380.
  17. D. R. Jonassen, G. S. Settles, and M. D. Tronosky, “Schlieren ‘PIV’ for turbulent flows,” Opt. Lasers Eng. 44, 190–207 (2006). [CrossRef]
  18. J. K. Sveen and S. B. Dalziel, “A dynamic masking technique for combined measurement of PIV and synthetic schlieren applied to internal gravity waves,” Meas. Sci. Technol. 16, 1954–1960 (2005). [CrossRef]
  19. S. B. Dalziel, M. Carr, J. K. Sveen, and P. A. Davies, “Simultaneous synthetic schlieren and PIV measurements for internal solitary waves,” Meas. Sci. Technol. 18, 533–547 (2007). [CrossRef]
  20. C. F. Ihle, S. B. Dalziel, and Y. Niño, “Simultaneous particle image velocimetry and synthetic schlieren measurement of an erupting thermal plume,” Meas. Sci. Technol. 20, 125402 (2009). [CrossRef]
  21. Y. Dossman, A. Paci, F. Auclair, and J. W. Floor, “Simultaneous velocity and density measurements for an energy based approach to internal waves generated over a ridge,” Exp. Fluids 51, 1013–1028 (2011). [CrossRef]
  22. A. Martínez-González, J. A. Guerrero-Viramontes, and D. Moreno-Hernández, “Temperature and velocity measurement fields of fluids using a schlieren system,” Appl. Opt. 51, 3519–3525 (2012). [CrossRef]
  23. E. D. Iffa, A. Rashid, A. Aziz, and A. S. Malik, “Velocity field measurement of a round jet using quantitative schlieren,” Appl. Opt. 50, 618–625 (2011). [CrossRef]
  24. O. N. Stavroudis, The Optics of Rays, Wavefronts, and Caustics (Academic, 1972).
  25. R. J. Goldstein and T. H. Kuehn, “Optical system for flow measurement: shadowgraph, schlieren, and interferometric techniques,” in Fluid Mechanics Measurement, R. J. Goldstein, ed. (Taylor & Francis, 1996), pp. 451–508.
  26. B. K. P. Horn and B. G. Schunck, “Determining optical flow,” J. Artificial Intelligence Res. 17, 185–203 (1981). [CrossRef]

Cited By

Alert me when this paper is cited

OSA is able to provide readers links to articles that cite this paper by participating in CrossRef's Cited-By Linking service. CrossRef includes content from more than 3000 publishers and societies. In addition to listing OSA journal articles that cite this paper, citing articles from other participating publishers will also be listed.

« Previous Article  |  Next Article »

OSA is a member of CrossRef.

CrossCheck Deposited