Recent progress in filtered Rayleigh scattering: Towards the simultaneous acquisition of pressure, temperature and three-component velocity fields

Abstract

The filtered Rayleigh scattering technique extended by the method of frequency scanning offers a viable option to efficiently characterize the aero-thermal properties of technical flows. The first part of the study is concerned with the identification and treatment of detrimental effects towards the methods uncertainty budget. Presented background correction as well as a novel approach with regard to the Rayleigh scattering's spectral distribution yields measurement accuracies for pressure, temperature and flow velocity below 15 hPa, 2.5 K and 2.7 m/s, respectively. Based on an observation of the plane of interest from multiple views, an FRS velocimeter is brought into use, which is capable to simultaneously acquire pressure, temperature as well as three-component velocity maps.