Hostname: page-component-78c5997874-v9fdk Total loading time: 0 Render date: 2024-11-18T03:11:21.971Z Has data issue: false hasContentIssue false
  • English
  • Français

A study of synthetic jets from rectangular and dual-circular orifices

Published online by Cambridge University Press:  04 July 2016

M. Watson ,
A. J. Jaworski  and
N. J. Wood
M. Watson
Affiliation:
Fluid Mechanics Research Group University of Manchester, UK
A. J. Jaworski
Affiliation:
Fluid Mechanics Research Group University of Manchester, UK
N. J. Wood
Affiliation:
Fluid Mechanics Research Group University of Manchester, UK
Get access Rights & Permissions [Opens in a new window]

Abstract

The results of an investigation into the effect of both the number of orifices and the geometry of these orifices on the fluid structures exiting from a synthetic jet actuator are presented. The experiments have used smoke and laser visualisation and single hotwire measurement techniques to establish the flow field exiting the various orifices and the fluid velocities in the exit plane of the orifice. The results indicate that the use of two small orifices can perhaps produce two coherent vortex rings with a total circulation greater than that found in the ring produced by a large, single orifice of equivalent area. However, they have also shown that there are three different types of interaction between two adjacent orifices, related to the spacing between them and the level of excitation applied to the diaphragm. In addition, these interactions may affect the overall level of circulation in different ways. Finally the results have shown that a rectangular orifice of a given exit plane area is more likely to produce a turbulent ring than the equivalent circular orifice due to a ‘smoothing’ process which endeavours to create an axisymmetric ring from a non-axisymmetric slug of fluid. This work has shown that when using synthetic jet actuators in flow control applications, care should be taken in selecting the spacing and geometry of the orifices used, as certain set-ups may be more suited to certain applications than others.

Type
Research Article
Information
The Aeronautical Journal , Volume 107 , Issue 1073 , July 2003 , pp. 427 - 434
Copyright
Copyright © Royal Aeronautical Society 2003 

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

1. Smith, B.L. and Glezer, A., The formation and evolution of synthetic jets, Physics of Fluids, 1998, 10, (9), pp 2281–2297.Google Scholar
2. Mallinson, S.G., Reizes, J.A. and Hong, G., An experimental and numerical study of synthetic jet flow, Aeronaut J, Jan 2001, 105, (1043), pp 41–49.Google Scholar
3. Smith, D.R., Amitay, M., Kibens, V., Parekh, D. and Glezer, A., Modification of lifting body aerodynamics using synthetic jet actuators, 1998, AIAA Paper, 98-0209.Google Scholar
4. Crook, A. and Wood, N.J., Measurements and visualisations of synthetic jets, 2001, AIAA Paper, 2001-0145.Google Scholar
5. Crook, A. and Wood, N.J., A parametric investigation of a synthetic jet in quiescent conditions, 2000, Ninth International Symposium on Flow Vis, Paper 67, Edinburgh, UK.Google Scholar
6. Crook, A., Crowther, W.J. and Wood, N.J., A parametric study of a synthetic jet in a cross flow, 2000, 22nd International Congress of Aeronautical Sciences, Harrogate, UK.Google Scholar
7. Gharib, M., Rambod, E. and Shariff, K., A universal time scale for vortex ring formation, J Fluid Mech, 1998, 360, pp 121–140.Google Scholar