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Frequency-selection mechanism in incompressible open-cavity flows via reflected instability waves
F Tuerke1, D Sciamarella2, L R Pastur3
1Departamento de Ingeniería Mecánica, Universidad de Buenos Aires, Ciudad Autónoma de Buenos Aires, C1063ACV Argentina and CONICET-Consejo Nacional de Investigaciones Científicas y Técnicas, C1083ACA Argentina and Université Paris Sud 11, 91400 Orsay, France.
Physical Review. E, Statistical, Nonlinear, and Soft Matter Physics
|February 14, 2015
Summary
This study explains nonharmonic mode coexistence in open-cavity flows using a new perspective on instability wave reflection. The findings align well with experimental data, offering a better understanding of fluid dynamics.
Area of Science:
- Fluid Dynamics
- Acoustics
- Aerodynamics
Background:
- Nonharmonic mode coexistence is a common phenomenon in the shear layer spectrum of open-cavity flows.
- Understanding this phenomenon is crucial for predicting and controlling flow instabilities.
Purpose of the Study:
- To present an alternative perspective on nonharmonic mode coexistence in open-cavity flows.
- To provide a theoretical framework that explains the observed frequencies.
Main Methods:
- Local linear stability analysis of perturbations to a 2D, incompressible, inviscid sheared flow over a cavity.
- Incorporation of the Kulikowskii coincidence condition to account for instability wave reflection within the cavity.
Main Results:
- A set of discrete, nonharmonic frequencies were obtained from the analysis.
- The theoretical frequencies show good agreement with experimental results from previous studies.
Conclusions:
- The proposed theoretical approach offers a valid explanation for nonharmonic mode coexistence in open-cavity flows.
- This work enhances the understanding of flow instabilities and acoustic emissions in cavity flows.
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