Thermodynamics Research Center / ThermoML | Journal of Chemical and Engineering Data

ABSTRACT

Refractive index matching (RIM) methods are widely used in combination with optical flow measurement techniques such as particle image velocimetry and laser Doppler velocimetry to investigate fluid flows. In applying RIM, matching the refractive indices of the fluid and solid eliminates the problem of refraction/reflection at the solid-liquid interface. An experimental analysis of the effects of salt concentration and temperature on the refractive index of potassium thiocyanate (KSCN) solutions is conducted to quantify its performance as a RIM solution that is used in flow experiments. This enables the researchers to control the refractive index of the test medium under different test conditions by manipulating the KSCN concentration in the solution. Empirical correlations are developed by fitting the refractive index results, which highlight a non-linear dependency