| Autor: |
Stavropoulos, Michael N., Mancinelli, Matteo, Jordan, Peter, Jaunet, Vincent, Weightman, Joel, Edgington-Mitchell, Daniel M., Nogueira, Petrônio A. S. |
| Předmět: |
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| Zdroj: |
Journal of Fluid Mechanics; 6/25/2023, Vol. 965, p1-29, 29p |
| Abstrakt: |
Spatial linear stability analysis is used to study the axisymmetric screech tones generated by twin converging round nozzles at low supersonic Mach numbers. Vortex-sheet and finite-thickness models allow for identification of the different waves supported by the flow at different conditions. Regions of the frequency-wavenumber domain for which the upstream-propagating guided jet modes are observed to be neutrally stable are observed to vary as a function of solution symmetry, jet separation, S, and the velocity profile used. Screech-frequency predictions performed using wavenumbers obtained from both models agree well with experimental data. Predictions obtained from the finite-thickness model better align with the screech tones measured experimentally and so are seen to be an improvement on predictions made with the vortex sheet. Additionally, results from the finite-thickness model predict both symmetric and antisymmetric screech tones for low S that are found in the vortex-sheet model only at greater S. The present results indicate that the feedback loop generating these screech tones is similar to that observed for single-jet resonance, with equivalent upstream and downstream modes. [ABSTRACT FROM AUTHOR] |
| Databáze: |
Complementary Index |
| Externí odkaz: |
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