Abstract
The global wall shear stress measurement technique using shear-sensitive liquid crystal (SSLC) is extended to wind tunnel measurements. Simple and common everyday equipment is used in the measurement; in particular a tungsten-halogen light bulb provides illumination and a saturation of SSLC coating color change with time is found. Spatial wall shear stress distributions of several typical flows are obtained using this technique, including wall-jet flow, vortex flow generated by a delta wing and junction flow behind a thin cylinder, although the magnitudes are not fully calibrated. The results demonstrate that SSLC technique can be extended to wind tunnel measurements with no complicated facilities used.
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Zhao, JS., Scholz, P. & Gu, LX. Measurement of surface shear stress vector distribution using shear-sensitive liquid crystal coatings. Acta Mech Sin 28, 1261–1270 (2012). https://doi.org/10.1007/s10409-012-0144-1
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DOI: https://doi.org/10.1007/s10409-012-0144-1