Development of a Thermo-Optical Sensor for Measurements of Wall Shear Stress Magnitude and Direction
In recent years, investigations regarding novel thermo-optical techniques for the visualization and quantification of wall shear stress distributions were conducted, , , . These techniques correlate the temperature field on a structure to the near wall flow. Based on these findings, a new sensor was developed that is capable of measuring skin friction magnitude and direction as well as visualizing the near wall flow. The new thermo-optical sensor presented in this paper was investigated numerically at first, to find suitable correlation parameters. In contrast to existing investigations, a unique correlation parameter was found that produces better and more reliable results than previously proposed parameters. With the help of the numerical results, a sensor was designed, built and tested in wind tunnel experiments.
KeywordsWall Shear Stress Skin Friction Wind Tunnel Experiment Adiabatic Wall Wall Shear Stress Distribution
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