Visualization and analysis of jet oscillation under transverse acoustic perturbation

Patricio de La Cuadra (1) , Christophe Vergez (2) , Benoît Fabre (3)

1 CITA - Centro de Investigacion en Tecnologias de Audio
2 LMA - Laboratoire de Mécanique et d'Acoustique [Marseille]
3 DALEMBERT - Institut Jean Le Rond d'Alembert

Schlieren flow visualizations of transverse oscillations of jets submitted to an acoustic perturbation are analyzed in this paper. The aim is to estimate the shape and the position of the median line of the jet. Two methods for image processing are proposed, based on complementary approaches~: inter image and intra image analysis. Synthesized images of an oscillating jet are used to validate each method and compare their performances in the case of noisy pictures. Illustrations are then shown on real laminar and turbulent jets. The results obtained using both methods are very close, showing their reliability. Applications investigated in this paper are focused on the estimation of the convection velocity of perturbations along the jet, and the influence of the Reynolds number and of the channel geometry upstream the jet formation.

Mots clés: jet oscillation; transverse perturbation; image analysis; convection; amplification

Domaines: Mécanique des fluides [physics.class-ph]; Mécanique des fluides [physics.class-ph]; Traitement du signal et de l'image [eess.SP]; Traitement du signal et de l'image [eess.SP]

Patricio de La Cuadra, Christophe Vergez, Benoît Fabre. Visualization and analysis of jet oscillation under transverse acoustic perturbation. Journal of Flow Visualization and Image Processing, 2007, 14 (4), pp.355-374. ⟨hal-00336209⟩