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Various aspects of camera settings and image processing in the calibration of thermo-chromic liquid crystals for accurate particle image thermometry measurements

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Abstract

Step-by-step calibration procedures of particle image thermometry (PIT) for non-invasive and accurate temperature measurements using thermo-chromic liquid crystals (TLCs) are described in this paper. The purpose of this study is to examine the effects of various aspects of camera settings and image and data processing on the calibration of TLCs, and reveal the optimal parameter settings for achieving the best calibration curve of temperature versus color. Based on this study, an optimal window size has been proposed for median filtering to achieve the best compromise between noise removal and retaining of the true color information of the original experimental photographs; an optimal white balance settings in terms of the color temperature has been revealed for the present optical system; and finally, an optimal configuration of neural networks has been identified for obtaining the best hue–temperature correlation for further experiments.

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References

  • Anderson MR, Baughn JW (2004) Hysteresis in liquid crystal thermography. J Heat Transf 126:339–346

    Article  Google Scholar 

  • Anderson MR, Baughn JW (2005) Liquid-crystal thermography: illumination spectral effects. Part 1—experiments. J Heat Transf 127:591–598

    Google Scholar 

  • Baughn JW, Anderson MR, Mayhew JE, Wolf JD (1999) Hysteresis and uncertainty of thermo-chromic liquid crystals temperature measurement based on hue. J Heat Transf 121:1067–1072

    Article  Google Scholar 

  • Bednarz T, Lei C, Patterson JC (2007) Particle image thermometry for natural convection flows. In: Proc. 16th Australasian fluid mechanics conference. pp 1165–1170

  • Bednarz T, Lei C, Patterson JC (2008) An experimental study of unsteady natural convection in a reservoir model cooled from the water surface. Exp Thermal Fluid Sci 32:844–856

    Article  Google Scholar 

  • Chan RH, Chuang-Wa H, Nikolova M (2005) Salt-and-pepper noise removal by median-type noise detectors and detail-preserving regularization. Image Process IEEE Trans 14:1479–1485

    Article  Google Scholar 

  • Fujisawa N, Funatani S (2000) Simultaneous measurement of temperature and velocity in a turbulent thermal convection by the extended range scanning liquid crystal visualization technique. Exp Fluids (Suppl)158–165

  • Gonzalez RC, Woods RE, Eddins SL (2004) Digital image processing using Matlab, Pearson Education Inc, Prentice Hall

  • Grassi W, Testi D, Della Vista D, Torelli G (2007) Calibration of a sheet of thermosensitive liquid crystals viewed non-orthogonally. Measurement 40:898–903

    Article  Google Scholar 

  • Grewal GS, Bharara M, Cobb JE, Dubey VN, Claremont DJ (2006) A novel approach to thermochromic liquid crystal calibration using neural networks. Meas Sci Tech 17:1918–1924

    Article  Google Scholar 

  • Koschan A, Abidi MA (2001) A comparison of median filter techniques for noise removal in color images. In: Proc. 7th German workshop on color image processing. pp 69–79

  • Park HG, Dabiri D, Gharib M (2001) Digital particle image velocimetry/thermometry and application to the wake of heated circular cylinder. Exp Fluids 30:327–338

    Article  Google Scholar 

  • Smith CR, Sabatino DR, Praisner TJ (2001) Temperature sensing with thermochromic liquid crystals. Exp Fluids 30:190–201

    Article  Google Scholar 

  • Stasiek JA (1997) Thermochromic liquid crystals and true color image processing in heat transfer and fluid-flow research. Heat Mass Transf 33:27–39

    Article  Google Scholar 

  • Stasiek JA, Kowalewski TA (2002) Thermochromic liquid crystals applied for heat transfer research. Opto-Electron Rev 10:1–10

    Google Scholar 

  • Tadeusiewicz R (1993) Neural networks (Sieci Neuronowe), Akademicka Oficyna Wydawnicza RM, Warsaw (in Polish)

  • Thakur A, Anand RS (2005) Image quality based comparative evaluation of wavelet filters in ultrasound speckle reduction. Digit Signal Process 15:445–465

    Article  Google Scholar 

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Authors and Affiliations

  1. CSIRO Earth Science and Resource Engineering, Technology Court, Pullenvale, QLD, 4069, Australia

    Tomasz P. Bednarz

  2. School of Civil Engineering, The University of Sydney, Sydney, NSW, 2006, Australia

    Chengwang Lei & John C. Patterson

Authors
  1. Tomasz P. Bednarz
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  2. Chengwang Lei
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  3. John C. Patterson
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Correspondence to Tomasz P. Bednarz.

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Bednarz, T.P., Lei, C. & Patterson, J.C. Various aspects of camera settings and image processing in the calibration of thermo-chromic liquid crystals for accurate particle image thermometry measurements. J Vis 13, 241–250 (2010). https://doi.org/10.1007/s12650-010-0038-x

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  • DOI: https://doi.org/10.1007/s12650-010-0038-x

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