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Acoustic streaming in annular thermoacoustic prime-movers
1Laboratoire de Physique de l'Etat Condense, UPRESA-CNRS 6087, Faculte des Sciences and Ecole Nationale Superieure d'Ingenieurs du Mans, Universite du Maine, Le Mans, France.
The Journal of the Acoustical Society of America
|September 29, 2000
Summary
Acoustic streaming in thermoacoustic prime-movers generates fluid circulation without moving parts. This directional flow significantly impacts heat transfer within the device, crucial for performance optimization.
Area of Science:
- Acoustics
- Thermodynamics
- Fluid Dynamics
Background:
- Thermoacoustic prime-movers utilize sound waves to generate heat or cold.
- Understanding fluid dynamics within these devices is key to improving efficiency.
- Acoustic streaming, the steady flow induced by sound waves, is a relevant phenomenon.
Purpose of the Study:
- To develop the theory of acoustic streaming in an annular thermoacoustic prime-mover.
- To investigate the fluid circulation generated by traveling wave excitation.
- To analyze the heat transfer implications of this induced mass flow.
Main Methods:
- Theoretical development of acoustic streaming.
- Analysis of fluid circulation above the traveling wave excitation threshold.
- Comparison of heat flux due to mass flow versus acoustically induced thermal diffusivity.
Main Results:
- Predicted fluid circulation in the absence of moving parts or external pressure gradients.
- The heat flux carried by the directional mass flow is comparable to or exceeds that from increased thermal diffusivity.
- Acoustic streaming plays a significant role in the overall heat transfer within the thermoacoustic stack.
Conclusions:
- Acoustic streaming is a fundamental mechanism in thermoacoustic prime-movers.
- The induced mass flow significantly contributes to heat transfer, impacting device performance.
- These findings are vital for optimizing the design and efficiency of thermoacoustic devices.
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