Multi-beam interferometric Rayleigh scattering technique for simultaneous 2-D quantitative measurement of multi-parameters in high speed flow field

[摘要] In order to diagnose the high-speed compressible turbulent flow field, a two-dimensional (2-D) multi-parameters measurement method based on mull-beam interferometric Rayleigh scattering (IRS) technique was proposed. Under the beam splitting of etalon, the Rayleigh scattering signals generated by the interaction between mull-beam laser probes and the flow field gas molecules formed 2-D interference measurement lattice. Each measurement point contained the thermodynamic and velocity information of the flow field corresponding to a specific spatial location. By calibrating the effective finesse and transmittance of the etalon at different incident angles, the measurement accuracy of temperature and density of high-order interferometric points was improved. A 2-D IRS measurement system was established by combining mull-beam laser probes, amplification imaging system and solid quartz etalon. A high speed jet was used to verify the technology. The distributions of temperature, density and velocity at different positions along the radial direction and axial direction of the nozzle were obtained. The results shown that the technique could be used to simultaneously measure the 2-D mull-parameter information of the flow field.

[发布日期] 2021-09-15

[关键词] Rayleigh scattering;Interference image;Multi-parameter measurements;Fabry-Perot etalon