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High amplitude nonlinear acoustic wave driven flow fields in cylindrical and conical resonators
Dion Savio Antao1, Bakhtier Farouk
1Department of Mechanical Engineering and Mechanics, Drexel University, Philadelphia, Pennsylvania 19104, USA.
The Journal of the Acoustical Society of America
|August 10, 2013
Summary
Conical resonators generate high-amplitude, shock-less acoustic waves, unlike cylindrical ones. This nonlinear acoustic output enhances performance in thermoacoustic refrigerators and mixers.
Area of Science:
- Acoustics
- Fluid Dynamics
- Thermodynamics
Background:
- Cylindrical acoustic resonators exhibit limitations in high-amplitude standing wave generation.
- Conical resonators offer a potential alternative for enhanced acoustic energy conversion.
Purpose of the Study:
- To simulate and analyze high-amplitude standing waves in cylindrical and conical resonators using computational fluid dynamics.
- To investigate the nonlinear acoustic behavior and potential applications of conical resonators.
Main Methods:
- High-fidelity computational fluid dynamic (CFD) modeling.
- Simulation of flow, pressure, and density fields.
- Validation against existing numerical data for cylindrical resonators.
Main Results:
- Conical resonators produce shock-less waves with peak acoustic overpressures 2-3 times initial pressure.
- Conical geometry converts linear acoustic input to high-energy, un-shocked nonlinear acoustic output.
- Nonlinear harmonic response investigated for CO2 and Argon at various piston amplitudes.
Conclusions:
- Conical resonators offer superior nonlinear acoustic performance compared to cylindrical resonators.
- High-amplitude nonlinear oscillations in conical resonators can improve pulse tube thermoacoustic refrigerators.
- Conical resonators show potential as efficient mixers in various applications.
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