Method for Spectra Estimation from High-Speed Experimental Data

Anne-Marie Schreyer (1, 2) , Lionel Larchevêque (2) , Pierre Dupont (2)

1 Direction des lanceurs
2 IUSTI - Institut universitaire des systèmes thermiques industriels

The present paper presents a technique to estimate spectra from experimental data sampled at discrete points in time. The interest of the current paper is to investigate spatiotemporal dependencies in supersonic turbulent flows like boundary layers and shock wave/turbulent boundary-layer interactions. The experimental data are measured by means of a dual-particle-image-velocimetry system that gives access to a certain amount of temporal information that is also in high-speed flows. The cross-correlation information in space made available by the dual-particle-image-velocimetry system can be used to reconstruct the autocorrelation for delay times ranging between the discrete points measured with the dual-particle-image-velocimetry system. This can be achieved for convection-dominated regions of the flow by moving into the convected frame of reference: similar to Taylor’s hypothesis. The principle and suitability of the suggested technique is demonstrated in a combined numerical–experimental approach. The large-eddy simulations give access to fully time-resolved data and can thus be used to verify the accuracy of the autocorrelation and spectra estimated from experimental data. Also, the choice of time delays for the measurements can be optimized based on the numerical results. Read More: http://arc.aiaa.org/doi/10.2514/1.J054370

Domaines: Mécanique des fluides [physics.class-ph]

Anne-Marie Schreyer, Lionel Larchevêque, Pierre Dupont. Method for Spectra Estimation from High-Speed Experimental Data. AIAA Journal, 2016, 54 (2), pp.557-568. ⟨10.2514/1.J054370⟩. ⟨hal-01455151⟩