Skip to Main content Skip to Navigation
Conference papers

Estimation of convection speed in underexpanded jets from schlieren pictures

Abstract : In this paper, the quality of the estimation of the convection velocity in jet shear layers using schlieren pictures is investigated. The aim is to discuss whether the convection velocity is likely to be biased if determined from schlieren images obtained at a high framerate, as in previous experiments using the phase shift method. For this, a numerical procedure is developed in order to generate schlieren-like images on the basis of simulation data, and applied to the results provided by the large-eddy simulation (LES) of an under-expanded round jet at an ideally expanded Mach number of 1.56. The results obtained from the schlieren pictures are compared with those obtained directly from the LES density fields. It is notably found that the location of the maximum of gray level fluctuations in the schlieren pictures corresponds well to that of the maximum of density fluctuations, and that the convection velocity estimated for low frequencies using schlieren pictures is underestimated for small separation distances between the two points used for the phase shift calculation.
Document type :
Conference papers
Complete list of metadata

https://hal.archives-ouvertes.fr/hal-02352884
Contributor : Christophe Bogey <>
Submitted on : Monday, April 19, 2021 - 4:49:02 PM
Last modification on : Tuesday, September 14, 2021 - 10:20:08 AM
Long-term archiving on: : Tuesday, July 20, 2021 - 7:19:58 PM

File

Castelain_27038.pdf
Files produced by the author(s)

Identifiers

Collections

Citation

Thomas Castelain, Romain Gojon, Bertrand Mercier, Christophe Bogey. Estimation of convection speed in underexpanded jets from schlieren pictures. 22nd AIAA/CEAS Aeroacoustics Conference, May 2016, Lyon, France. pp.1-14, ⟨10.2514/6.2016-2984⟩. ⟨hal-02352884⟩

Share

Metrics

Record views

81

Files downloads

63