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On wavelike perturbations in a free jet travelling faster than the mean flow in the jet

Published online by Cambridge University Press:  29 March 2006

D. Bechert  and
E. Pfizenmaier
D. Bechert
Affiliation:
DFVLR-Institut für Turbulenzforschung, 1 Berlin 12. Müller-Breslau-Strasse 8
E. Pfizenmaier
Affiliation:
DFVLR-Institut für Turbulenzforschung, 1 Berlin 12. Müller-Breslau-Strasse 8
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Abstract

The phase velocities of axial disturbances to a free jet have been investigated experimentally. For a certain range of low Strouhal numbers previous theories predicted the existence of phase velocities exceeding the mean velocity of the jet. These ‘ultra-fast’ phase velocities were found in the present experiments too.

Type
Research Article
Information
Journal of Fluid Mechanics , Volume 72 , Issue 2 , 25 November 1975 , pp. 341 - 352
Copyright
© 1975 Cambridge University Press

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References

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