Measurement Accuracy and Application of Liquid Crystal Thermography Technique in Turbulent Flow Heat Transfer

Abstract

Abstract:

By conducting a calibration experiment, the parameters affecting the measurement accuracy of the liquid crystal thermography has been analyzed, and the methods for improving the measurement accuracy have been developed. Additionally, the application of the liquid crystal thermography technique in the study of turbulent flow heat transfer has been discussed. The experimental results showed that using the color imaging processing techniques, properly controlling the coating thickness (over 20 μm), keeping the lighting angle as small as possible, and using a finely prepared thermochromatic liquid crystal (TLC) coating can distinctively improve the measurement accuracy of the liquid crystal thermography. Finally, the applications of the steady and transient liquid crystal thermography technique in the study of the turbulent flow heat transfer have been described, which is related to the convective cooling of the aero-engine turbine blade.

Key words: liquid crystal thermography, heat transfer measurements, cooling technology, turbulent flow

CLC Number:

V 235.1

XU Yamin,RAO Yu. Measurement Accuracy and Application of Liquid Crystal Thermography Technique in Turbulent Flow Heat Transfer[J]. Journal of Shanghai Jiaotong University, 2013, 47(08): 1185-1190.

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