A feedback model of the edge tone, using the adjoint Orr–Sommerfeld equation
The description of the feedback mechanism is one of the crucial points in the understanding of self-sustained flow oscillations, such as the edge tone or the cavity tone. In this paper a new model for the edge tone, using linear adjoint modes is proposed for low speeds, when acoustic effects are neg...
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Published in | Journal of fluid mechanics Vol. 915 |
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Main Authors | , , |
Format | Journal Article |
Language | English |
Published |
Cambridge, UK
Cambridge University Press
09.03.2021
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Subjects | |
Online Access | Get full text |
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Summary: | The description of the feedback mechanism is one of the crucial points in the understanding of self-sustained flow oscillations, such as the edge tone or the cavity tone. In this paper a new model for the edge tone, using linear adjoint modes is proposed for low speeds, when acoustic effects are negligible. The two crucial points of the model are (i) a new relationship between the jet oscillation and the generated vortex at the edge tip and (ii) a new model for the effect of the generated vortex on the oscillation. The frequency corresponding to the optimum open-loop gain of the feedback mechanism was compared with experimental data and good agreement was found. |
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ISSN: | 0022-1120 1469-7645 |
DOI: | 10.1017/jfm.2021.47 |