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Published on: August 27, 2013
An acoustic streaming instability in thermoacoustic devices utilizing jet pumps
1Condensed Matter and Thermal Physics Group, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA. backhaus@lanl.gov
The Journal of the Acoustical Society of America
|March 27, 2003
Summary
Jet pumps can prevent heat leaks in thermoacoustic engines and refrigerators. A new stability criterion predicts when these jet pumps reliably suppress unwanted streaming, improving efficiency.
Area of Science:
- Thermodynamics
- Acoustic Engineering
- Mechanical Engineering
Background:
- Thermoacoustic-Stirling hybrid engines and pulse tube refrigerators often suffer from streaming, leading to heat leaks and reduced efficiency.
- Jet pumps are used to suppress this streaming, offering a reliable solution without moving parts.
- However, jet pump performance can be unstable in certain conditions.
Purpose of the Study:
- To develop a stability criterion for jet pump streaming suppression.
- To predict the conditions under which jet pumps reliably suppress streaming in specific devices.
- To enhance the efficiency and reliability of thermoacoustic engines and refrigerators.
Main Methods:
- Acoustic modeling of regenerators and jet pumps.
- Derivation of a stability criterion based on acoustic properties.
- Analysis of streaming suppression in thermoacoustic devices.
Main Results:
- A stability criterion has been successfully derived.
- The criterion predicts the onset of instability in jet pump streaming suppression.
- The model provides insights into the acoustic behavior within the devices.
Conclusions:
- The derived stability criterion enables prediction of reliable jet pump operation.
- Understanding these acoustic dynamics is crucial for optimizing engine and refrigerator performance.
- This work contributes to the development of more efficient and stable thermoacoustic systems.
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