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Gap seal dissipation in linear alternators
Eran Gonen1, Gershon Grossman2
1Qnergy, Ein Harod Ihud 18960, Israel.
The Journal of the Acoustical Society of America
|April 30, 2015
Summary
This study enhances thermoacoustic-engine models by including piston-cylinder friction and blow-by losses. This improved model accurately predicts electroacoustic conversion efficiency and optimal electrical load resistance.
Area of Science:
- Thermodynamics
- Acoustics
- Electromechanical Systems
Background:
- Previous thermoacoustic-electrodynamic models often neglected crucial friction and blow-by losses.
- These losses arise from piston movement within the tight-fitting gap of motor/alternators.
Purpose of the Study:
- To develop an extended model incorporating viscous friction and blow-by losses.
- To improve the accuracy of electroacoustic conversion efficiency estimation.
- To determine optimal load resistance for maximizing electrical power output.
Main Methods:
- Developed a new thermodynamic model accounting for piston-cylinder gap losses.
- Empirically determined piston-cylinder gap parameters.
- Validated model predictions against experimental data from two thermoacoustic engines.
Main Results:
- The enhanced model provides more accurate electroacoustic conversion efficiency predictions.
- The model successfully identifies optimal load resistance for electrical power generation.
- Model predictions showed excellent agreement with experimental measurements.
Conclusions:
- Including viscous friction and blow-by losses is essential for accurate thermoacoustic-electrodynamic system modeling.
- The developed model offers a valuable tool for optimizing the design and performance of thermoacoustic power generation systems.
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