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Updated: Aug 3, 2026
06:42
Magnetically Induced Rotating Rayleigh-Taylor Instability
Published on: March 3, 2017
Nonlinear saturation of the thermoacoustic instability
1Department of Mechanical Engineering, The Johns Hopkins University, Baltimore, Maryland 21218, USA.
The Journal of the Acoustical Society of America
|June 30, 2000
Summary
A new theory explains thermoacoustic instability in gas-filled tubes. It details how initial growth, nonlinear evolution, and saturation depend on factors like temperature difference and tube geometry.
Area of Science:
- Fluid dynamics
- Acoustics
- Thermodynamics
Background:
- Thermoacoustic instability is a phenomenon in gas-filled tubes.
- Understanding its nonlinear behavior is crucial for applications.
Purpose of the Study:
- Develop a weakly nonlinear theory for thermoacoustic instability in the time domain.
- Obtain explicit results for the instability's evolution and saturation.
Main Methods:
- Exploited the difference between instability time scale and standing wave period.
- Extended perturbation expansion to fourth order.
Main Results:
- Derived explicit results for initial growth, nonlinear evolution, and saturation.
- Illustrated the dependence of saturation amplitude on various parameters.
Conclusions:
- The developed theory provides a framework for analyzing thermoacoustic instability.
- Results highlight the influence of temperature difference, geometry, and fluid properties on saturation amplitude.
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