Abstract
The use of modern ultra-high speed cameras to acquire time-resolved schlieren image sequences of supersonic jet impingement is presented. The use of these cameras, with framerates of up to 1 million frames per second, allows for the first time-resolved visualizations of the impinging jet acoustic feedback loop. The role of upstream travelling acoustic waves in generating perturbations in the jet shear layer at the nozzle exit is also directly observed for the first time. The arrival of the acoustic wave at the nozzle lip generates a sinusoidal variation in density gradient that persists until a distance of \(\frac{x}{d}=0.3\). A structure that rapidly evolves into a large-scale vortex ring forms at the trailing edge of this initial instability, first observed at approximately \(\frac{x}{d}=0.25\).
Graphical abstract
This is a preview of subscription content, log in via an institution to check access.
Similar content being viewed by others
References
Alvi FS, Lou H, Shih C, Kumar R (2008) Experimental study of physical mechanisms in the control of supersonic impinging jets using microjets. J Fluid Mech 613:55–83
Donaldson C, Snedeker R (1971) A study of free jet impingement. Part 1. Mean properties of free and impinging jets. J Fluid Mech 45(2):281–319
Henderson B (2002) The connection between sound production and jet structure of the supersonic impinging jet. J Acoust Soc Am 111(2):735–774
Henderson B, Powell A (1993) Experiments concerning tones produced by an axisymmetic choked jet impinging on a flat plate. J Sound Vib 168(2):307–326
Henderson B, Bridges J, Wernet M (2005) An experimental study of the oscillatory flow structure of tone-producing supersonic impinging jets. J Fluid Mech 542:115–137
Henderson LF (1966) Experiments on the impingement of a supersonic jet on a flat plate. J Appl Math Phys 17:119–142
Ho C, Nosseir NS (1981) Dynamics of an impinging jet. I. The feedback phenomenon. J Fluid Mech 105:119–142
Manning T (1999) A numerical investigation of sound generation in supersonic jet screech. PhD thesis, Stanford University
Marsh A (1961) Noise measurements around a subsonic air jet impinging on a plane, rigid surface. J Acoust Soc Am 33:1065–1066
Powell A (1988) The sound-producing oscillations of round underexpanded jets impinging on normal plates. J Acoust Soc Am 83:515–533
Risborg A, Soria J (2008) High-speed optical measurements of an underexpanded supersonic jet impining on an inclined plate. In: 28th international congress on high-speed imaging and photonics
Tam C (1995) Supersonic jet noise. Annu Rev Fluid Mech 27:17–43
Acknowledgments
The authors would like to acknowledge the funding of the Australian Research Council in supporting this research.
Author information
Authors and Affiliations
Corresponding author
Electronic supplementary material
Below is the link to the electronic supplementary material.
Supplementary material 1 (AVI 1,922 kb)
Rights and permissions
About this article
Cite this article
Mitchell, D.M., Honnery, D.R. & Soria, J. The visualization of the acoustic feedback loop in impinging underexpanded supersonic jet flows using ultra-high frame rate schlieren. J Vis 15, 333–341 (2012). https://doi.org/10.1007/s12650-012-0139-9
Received:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s12650-012-0139-9